Move assert to AssertJ

This commit moves project-based assertions to regular AssertJ Assert
classes. `ProjectStructure` is now an assert provider so that it can
be used with the standard `assertThat` method.

Specialized assertions are provided for the supported build systems as
well as text-based content.

Closes gh-764

initializr-docs/pom.xml

@@ -59,11 +59,6 @@
 			<artifactId>javax.servlet-api</artifactId>
 			<optional>true</optional>
 		</dependency>
-		<dependency>
-			<groupId>org.assertj</groupId>
-			<artifactId>assertj-core</artifactId>
-			<optional>true</optional>
-		</dependency>
 
 		<dependency>
 			<groupId>org.junit.jupiter</groupId>

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/AbstractComplianceTests.java

@@ -28,7 +28,6 @@ import io.spring.initializr.generator.project.ProjectDescription;
 import io.spring.initializr.generator.project.ProjectGenerationContext;
 import io.spring.initializr.generator.project.ResolvedProjectDescription;
 import io.spring.initializr.generator.test.InitializrMetadataTestBuilder;
-import io.spring.initializr.generator.test.project.ProjectAssert;
 import io.spring.initializr.generator.test.project.ProjectGeneratorTester;
 import io.spring.initializr.generator.test.project.ProjectStructure;
 import io.spring.initializr.generator.version.Version;
@@ -55,26 +54,26 @@ public abstract class AbstractComplianceTests {
 		this.tempDir = dir;
 	}
 
-	protected ProjectAssert generateProject(Language language, BuildSystem buildSystem, String version) {
+	protected ProjectStructure generateProject(Language language, BuildSystem buildSystem, String version) {
 		return generateProject(language, buildSystem, version, (description) -> {
 		});
 	}
 
-	protected ProjectAssert generateProject(Language language, BuildSystem buildSystem, String version,
+	protected ProjectStructure generateProject(Language language, BuildSystem buildSystem, String version,
 			Consumer<ProjectDescription> descriptionCustomizer) {
 		InitializrMetadata metadata = InitializrMetadataTestBuilder.withDefaults().addDependencyGroup("web", WEB)
 				.build();
 		return generateProject(language, buildSystem, version, descriptionCustomizer, metadata);
 	}
 
-	protected ProjectAssert generateProject(Language language, BuildSystem buildSystem, String version,
+	protected ProjectStructure generateProject(Language language, BuildSystem buildSystem, String version,
 			Consumer<ProjectDescription> descriptionCustomizer, Consumer<ProjectGenerationContext> contextCustomizer) {
 		InitializrMetadata metadata = InitializrMetadataTestBuilder.withDefaults().addDependencyGroup("web", WEB)
 				.build();
 		return generateProject(language, buildSystem, version, descriptionCustomizer, metadata, contextCustomizer);
 	}
 
-	protected ProjectAssert generateProject(Language language, BuildSystem buildSystem, String version,
+	protected ProjectStructure generateProject(Language language, BuildSystem buildSystem, String version,
 			Consumer<ProjectDescription> descriptionCustomizer, InitializrMetadata metadata) {
 		return generateProject(language, buildSystem, version, descriptionCustomizer, metadata,
 				(projectGenerationContext) -> {
@@ -82,7 +81,7 @@ public abstract class AbstractComplianceTests {
 
 	}
 
-	private ProjectAssert generateProject(Language language, BuildSystem buildSystem, String version,
+	private ProjectStructure generateProject(Language language, BuildSystem buildSystem, String version,
 			Consumer<ProjectDescription> descriptionCustomizer, InitializrMetadata metadata,
 			Consumer<ProjectGenerationContext> contextCustomizer) {
 		ProjectGeneratorTester projectTester = new ProjectGeneratorTester().withDirectory(this.tempDir)
@@ -91,9 +90,7 @@ public abstract class AbstractComplianceTests {
 				.withDescriptionCustomizer(descriptionCustomizer)
 				.withContextInitializer((context) -> setupProjectGenerationContext(metadata, context))
 				.withContextInitializer(contextCustomizer);
-		ProjectStructure projectStructure = projectTester.generate(new ProjectDescription());
-		Path resolve = projectStructure.resolve("");
-		return new ProjectAssert(resolve);
+		return projectTester.generate(new ProjectDescription());
 	}
 
 	private void setupProjectGenerationContext(InitializrMetadata metadata, ProjectGenerationContext context) {

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/ProjectGeneratorIntegrationTests.java

@@ -17,7 +17,6 @@
 package io.spring.initializr.generator.spring;
 
 import java.nio.file.Path;
-import java.util.List;
 
 import io.spring.initializr.generator.buildsystem.maven.MavenBuildSystem;
 import io.spring.initializr.generator.language.java.JavaLanguage;
@@ -26,6 +25,7 @@ import io.spring.initializr.generator.project.ProjectGenerationConfiguration;
 import io.spring.initializr.generator.project.ProjectGenerator;
 import io.spring.initializr.generator.test.InitializrMetadataTestBuilder;
 import io.spring.initializr.generator.test.project.ProjectGeneratorTester;
+import io.spring.initializr.generator.test.project.ProjectStructure;
 import io.spring.initializr.generator.version.Version;
 import io.spring.initializr.metadata.InitializrMetadata;
 import org.junit.jupiter.api.BeforeEach;
@@ -58,8 +58,8 @@ class ProjectGeneratorIntegrationTests {
 		description.setLanguage(new JavaLanguage());
 		description.setGroupId("com.example");
 		description.setBaseDirectory("test/demo-app");
-		List<String> relativePaths = this.projectTester.generate(description).getRelativePathsOfProjectFiles();
-		assertThat(relativePaths).containsOnly("test/demo-app/.gitignore", "test/demo-app/pom.xml",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).filePaths().containsOnly("test/demo-app/.gitignore", "test/demo-app/pom.xml",
 				"test/demo-app/mvnw", "test/demo-app/mvnw.cmd",
 				"test/demo-app/.mvn/wrapper/MavenWrapperDownloader.java",
 				"test/demo-app/.mvn/wrapper/maven-wrapper.properties", "test/demo-app/.mvn/wrapper/maven-wrapper.jar",

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/build/BuildComplianceTests.java

@@ -28,7 +28,7 @@ import io.spring.initializr.generator.language.kotlin.KotlinLanguage;
 import io.spring.initializr.generator.packaging.Packaging;
 import io.spring.initializr.generator.spring.AbstractComplianceTests;
 import io.spring.initializr.generator.test.InitializrMetadataTestBuilder;
-import io.spring.initializr.generator.test.project.ProjectAssert;
+import io.spring.initializr.generator.test.project.ProjectStructure;
 import io.spring.initializr.generator.version.Version;
 import io.spring.initializr.generator.version.VersionProperty;
 import io.spring.initializr.metadata.BillOfMaterials;
@@ -41,6 +41,8 @@ import org.junit.jupiter.params.provider.MethodSource;
 
 import org.springframework.core.io.ClassPathResource;
 
+import static org.assertj.core.api.Assertions.assertThat;
+
 /**
  * Build compliance tests.
  *
@@ -86,9 +88,8 @@ class BuildComplianceTests extends AbstractComplianceTests {
 	}
 
 	private void testCurrentGenerationJar(Language language, BuildSystem build, String fileName) {
-		ProjectAssert project = generateProject(language, build, "2.1.1.RELEASE");
-		project.sourceCodeAssert(fileName)
-				.equalsTo(new ClassPathResource("project/" + language + "/standard/" + getAssertFileName(fileName)));
+		assertThat(generateProject(language, build, "2.1.1.RELEASE")).textFile(fileName).hasSameContentAs(
+				new ClassPathResource("project/" + language + "/standard/" + getAssertFileName(fileName)));
 	}
 
 	@ParameterizedTest
@@ -110,11 +111,11 @@ class BuildComplianceTests extends AbstractComplianceTests {
 	}
 
 	private void testCurrentGenerationWar(Language language, BuildSystem build, String fileName) {
-		ProjectAssert project = generateProject(language, build, "2.1.1.RELEASE", (description) -> {
+		ProjectStructure project = generateProject(language, build, "2.1.1.RELEASE", (description) -> {
 			description.addDependency("web", MetadataBuildItemMapper.toDependency(WEB));
 			description.setPackaging(Packaging.forId("war"));
 		});
-		project.sourceCodeAssert(fileName).equalsTo(
+		assertThat(project).textFile(fileName).hasSameContentAs(
 				new ClassPathResource("project/" + language + "/standard/war-" + getAssertFileName(fileName)));
 	}
 
@@ -137,9 +138,9 @@ class BuildComplianceTests extends AbstractComplianceTests {
 	}
 
 	private void testNextGenerationJar(Language language, BuildSystem build, String fileName) {
-		ProjectAssert project = generateProject(language, build, "2.2.0.RELEASE");
-		project.sourceCodeAssert(fileName)
-				.equalsTo(new ClassPathResource("project/" + language + "/next/" + getAssertFileName(fileName)));
+		ProjectStructure project = generateProject(language, build, "2.2.0.RELEASE");
+		assertThat(project).textFile(fileName).hasSameContentAs(
+				new ClassPathResource("project/" + language + "/next/" + getAssertFileName(fileName)));
 	}
 
 	@ParameterizedTest
@@ -161,24 +162,24 @@ class BuildComplianceTests extends AbstractComplianceTests {
 	}
 
 	private void testPreviousGenerationJar(Language language, BuildSystem build, String fileName) {
-		ProjectAssert project = generateProject(language, build, "1.5.18.RELEASE");
-		project.sourceCodeAssert(fileName)
-				.equalsTo(new ClassPathResource("project/" + language + "/previous/" + getAssertFileName(fileName)));
+		ProjectStructure project = generateProject(language, build, "1.5.18.RELEASE");
+		assertThat(project).textFile(fileName).hasSameContentAs(
+				new ClassPathResource("project/" + language + "/previous/" + getAssertFileName(fileName)));
 	}
 
 	@ParameterizedTest
 	@MethodSource("parameters")
 	void kotlinJava11(BuildSystem build, String fileName) {
-		ProjectAssert project = generateProject(kotlin, build, "2.1.1.RELEASE",
+		ProjectStructure project = generateProject(kotlin, build, "2.1.1.RELEASE",
 				(description) -> description.setLanguage(Language.forId(kotlin.id(), "11")));
-		project.sourceCodeAssert(fileName)
-				.equalsTo(new ClassPathResource("project/" + build + "/kotlin-java11-" + getAssertFileName(fileName)));
+		assertThat(project).textFile(fileName).hasSameContentAs(
+				new ClassPathResource("project/" + build + "/kotlin-java11-" + getAssertFileName(fileName)));
 	}
 
 	@ParameterizedTest
 	@MethodSource("parameters")
 	void versionOverride(BuildSystem build, String fileName) {
-		ProjectAssert project = generateProject(java, build, "2.1.1.RELEASE",
+		ProjectStructure project = generateProject(java, build, "2.1.1.RELEASE",
 				(description) -> description.addDependency("web", MetadataBuildItemMapper.toDependency(WEB)),
 				(projectGenerationContext) -> projectGenerationContext.registerBean(BuildCustomizer.class,
 						() -> (projectBuild) -> {
@@ -186,7 +187,7 @@ class BuildComplianceTests extends AbstractComplianceTests {
 									"0.1.0.RELEASE");
 							projectBuild.addVersionProperty(VersionProperty.of("spring-bar.version"), "0.2.0.RELEASE");
 						}));
-		project.sourceCodeAssert(fileName).equalsTo(
+		assertThat(project).textFile(fileName).hasSameContentAs(
 				new ClassPathResource("project/" + build + "/version-override-" + getAssertFileName(fileName)));
 	}
 
@@ -199,10 +200,10 @@ class BuildComplianceTests extends AbstractComplianceTests {
 		bom.setVersionProperty("foo.version");
 		InitializrMetadata metadata = InitializrMetadataTestBuilder.withDefaults().addDependencyGroup("foo", foo)
 				.addBom("the-bom", bom).build();
-		ProjectAssert project = generateProject(java, build, "2.1.1.RELEASE",
+		ProjectStructure project = generateProject(java, build, "2.1.1.RELEASE",
 				(description) -> description.addDependency("foo", MetadataBuildItemMapper.toDependency(foo)), metadata);
-		project.sourceCodeAssert(fileName)
-				.equalsTo(new ClassPathResource("project/" + build + "/bom-property-" + getAssertFileName(fileName)));
+		assertThat(project).textFile(fileName).hasSameContentAs(
+				new ClassPathResource("project/" + build + "/bom-property-" + getAssertFileName(fileName)));
 	}
 
 	@ParameterizedTest
@@ -213,12 +214,12 @@ class BuildComplianceTests extends AbstractComplianceTests {
 		foo.setScope(Dependency.SCOPE_COMPILE_ONLY);
 		InitializrMetadata metadata = InitializrMetadataTestBuilder.withDefaults()
 				.addDependencyGroup("core", "web", "data-jpa").addDependencyGroup("foo", foo).build();
-		ProjectAssert project = generateProject(java, build, "2.1.1.RELEASE", (description) -> {
+		ProjectStructure project = generateProject(java, build, "2.1.1.RELEASE", (description) -> {
 			description.addDependency("foo", MetadataBuildItemMapper.toDependency(foo));
 			description.addDependency("web", MetadataBuildItemMapper.toDependency(WEB));
 			description.addDependency("data-jpa", MetadataBuildItemMapper.toDependency(dataJpa));
 		}, metadata);
-		project.sourceCodeAssert(fileName).equalsTo(
+		assertThat(project).textFile(fileName).hasSameContentAs(
 				new ClassPathResource("project/" + build + "/compile-only-dependency-" + getAssertFileName(fileName)));
 	}
 
@@ -232,13 +233,13 @@ class BuildComplianceTests extends AbstractComplianceTests {
 		InitializrMetadata metadata = InitializrMetadataTestBuilder.withDefaults()
 				.addDependencyGroup("core", "web", "data-jpa")
 				.addDependencyGroup("configuration-processor", annotationProcessor).build();
-		ProjectAssert project = generateProject(java, build, "2.1.1.RELEASE", (description) -> {
+		ProjectStructure project = generateProject(java, build, "2.1.1.RELEASE", (description) -> {
 			description.addDependency("configuration-processor",
 					MetadataBuildItemMapper.toDependency(annotationProcessor));
 			description.addDependency("web", MetadataBuildItemMapper.toDependency(WEB));
 			description.addDependency("data-jpa", MetadataBuildItemMapper.toDependency(dataJpa));
 		}, metadata);
-		project.sourceCodeAssert(fileName).equalsTo(new ClassPathResource(
+		assertThat(project).textFile(fileName).hasSameContentAs(new ClassPathResource(
 				"project/" + build + "/annotation-processor-dependency-" + getAssertFileName(fileName)));
 	}
 
@@ -258,10 +259,10 @@ class BuildComplianceTests extends AbstractComplianceTests {
 		fooBom.getAdditionalBoms().add("biz-bom");
 		InitializrMetadata metadata = InitializrMetadataTestBuilder.withDefaults().addDependencyGroup("foo", foo)
 				.addBom("foo-bom", fooBom).addBom("bar-bom", barBom).addBom("biz-bom", bizBom).build();
-		ProjectAssert project = generateProject(java, build, "2.1.1.RELEASE",
+		ProjectStructure project = generateProject(java, build, "2.1.1.RELEASE",
 				(description) -> description.addDependency("foo", MetadataBuildItemMapper.toDependency(foo)), metadata);
-		project.sourceCodeAssert(fileName)
-				.equalsTo(new ClassPathResource("project/" + build + "/bom-ordering-" + getAssertFileName(fileName)));
+		assertThat(project).textFile(fileName).hasSameContentAs(
+				new ClassPathResource("project/" + build + "/bom-ordering-" + getAssertFileName(fileName)));
 	}
 
 	@ParameterizedTest
@@ -274,12 +275,12 @@ class BuildComplianceTests extends AbstractComplianceTests {
 		InitializrMetadata metadata = InitializrMetadataTestBuilder.withDefaults().addDependencyGroup("test", foo, bar)
 				.addRepository("foo-repository", "foo-repo", "https://example.com/foo", false)
 				.addRepository("bar-repository", "bar-repo", "https://example.com/bar", true).build();
-		ProjectAssert project = generateProject(java, build, "2.1.1.RELEASE", (description) -> {
+		ProjectStructure project = generateProject(java, build, "2.1.1.RELEASE", (description) -> {
 			description.addDependency("foo", MetadataBuildItemMapper.toDependency(foo));
 			description.addDependency("bar", MetadataBuildItemMapper.toDependency(bar));
 		}, metadata);
-		project.sourceCodeAssert(fileName)
-				.equalsTo(new ClassPathResource("project/" + build + "/repositories-" + getAssertFileName(fileName)));
+		assertThat(project).textFile(fileName).hasSameContentAs(
+				new ClassPathResource("project/" + build + "/repositories-" + getAssertFileName(fileName)));
 	}
 
 	@ParameterizedTest
@@ -288,11 +289,11 @@ class BuildComplianceTests extends AbstractComplianceTests {
 		Dependency foo = Dependency.withId("foo", "org.acme", "foo");
 		InitializrMetadata metadata = InitializrMetadataTestBuilder.withDefaults().addDependencyGroup("test", foo)
 				.build();
-		ProjectAssert project = generateProject(java, build, "2.1.1.RELEASE", (description) -> {
+		ProjectStructure project = generateProject(java, build, "2.1.1.RELEASE", (description) -> {
 			description.setPlatformVersion(Version.parse("2.2.0.M1"));
 			description.addDependency("foo", MetadataBuildItemMapper.toDependency(foo));
 		}, metadata);
-		project.sourceCodeAssert(fileName).equalsTo(
+		assertThat(project).textFile(fileName).hasSameContentAs(
 				new ClassPathResource("project/" + build + "/repositories-milestone-" + getAssertFileName(fileName)));
 	}
 

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/build/gradle/GradleKtsProjectGenerationConfigurationTests.java

@@ -16,10 +16,7 @@
 
 package io.spring.initializr.generator.spring.build.gradle;
 
-import java.io.IOException;
-import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.List;
 import java.util.stream.Stream;
 
 import io.spring.initializr.generator.buildsystem.BuildWriter;
@@ -92,19 +89,16 @@ class GradleKtsProjectGenerationConfigurationTests {
 
 	@ParameterizedTest(name = "Spring Boot {0}")
 	@MethodSource("gradleWrapperParameters")
-	void gradleWrapperIsContributedWhenGeneratingGradleKtsProject(String platformVersion, String expectedGradleVersion)
-			throws IOException {
+	void gradleWrapperIsContributedWhenGeneratingGradleKtsProject(String platformVersion,
+			String expectedGradleVersion) {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse(platformVersion));
 		description.setLanguage(new JavaLanguage());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		List<String> relativePaths = projectStructure.getRelativePathsOfProjectFiles();
-		assertThat(relativePaths).contains("gradlew", "gradlew.bat", "gradle/wrapper/gradle-wrapper.properties",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).containsFiles("gradlew", "gradlew.bat", "gradle/wrapper/gradle-wrapper.properties",
 				"gradle/wrapper/gradle-wrapper.jar");
-		try (Stream<String> lines = Files.lines(projectStructure.resolve("gradle/wrapper/gradle-wrapper.properties"))) {
-			assertThat(lines.filter((line) -> line.contains(String.format("gradle-%s-bin.zip", expectedGradleVersion))))
-					.hasSize(1);
-		}
+		assertThat(project).textFile("gradle/wrapper/gradle-wrapper.properties")
+				.containsOnlyOnce(String.format("gradle-%s-bin.zip", expectedGradleVersion));
 	}
 
 	@Test
@@ -114,10 +108,9 @@ class GradleKtsProjectGenerationConfigurationTests {
 		description.setLanguage(new JavaLanguage("11"));
 		description.addDependency("acme",
 				Dependency.withCoordinates("com.example", "acme").scope(DependencyScope.COMPILE).build());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).contains("build.gradle.kts");
-		List<String> lines = projectStructure.readAllLines("build.gradle.kts");
-		assertThat(lines).containsExactly("plugins {", "    id(\"org.springframework.boot\") version \"2.1.0.RELEASE\"",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("build.gradle.kts").containsExactly("plugins {",
+				"    id(\"org.springframework.boot\") version \"2.1.0.RELEASE\"",
 				"    id(\"io.spring.dependency-management\") version \"1.0.6.RELEASE\"", "    java", "}", "",
 				"group = \"com.example\"", "version = \"0.0.1-SNAPSHOT\"",
 				"java.sourceCompatibility = JavaVersion.VERSION_11", "", "repositories {", "    mavenCentral()", "}",
@@ -131,8 +124,9 @@ class GradleKtsProjectGenerationConfigurationTests {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.1.0.RELEASE"));
 		description.setLanguage(new JavaLanguage("11"));
-		List<String> lines = this.projectTester.generate(description).readAllLines("build.gradle.kts");
-		assertThat(lines).contains("    id(\"io.spring.dependency-management\") version \"1.0.6.RELEASE\"");
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("build.gradle.kts").lines()
+				.contains("    id(\"io.spring.dependency-management\") version \"1.0.6.RELEASE\"");
 	}
 
 	@Test
@@ -140,10 +134,11 @@ class GradleKtsProjectGenerationConfigurationTests {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.1.0.RELEASE"));
 		description.setLanguage(new JavaLanguage("11"));
-		List<String> lines = this.projectTester
+		ProjectStructure project = this.projectTester
 				.withBean(DependencyManagementPluginVersionResolver.class, () -> (d) -> "1.5.1.RC1")
-				.generate(description).readAllLines("build.gradle.kts");
-		assertThat(lines).contains("    id(\"io.spring.dependency-management\") version \"1.5.1.RC1\"");
+				.generate(description);
+		assertThat(project).textFile("build.gradle.kts").lines()
+				.contains("    id(\"io.spring.dependency-management\") version \"1.5.1.RC1\"");
 	}
 
 	@Test
@@ -152,9 +147,8 @@ class GradleKtsProjectGenerationConfigurationTests {
 		description.setPlatformVersion(Version.parse("2.1.0.RELEASE"));
 		description.setLanguage(new JavaLanguage());
 		description.setPackaging(new WarPackaging());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).contains("build.gradle.kts");
-		assertThat(projectStructure.readAllLines("build.gradle.kts")).containsOnlyOnce("    war");
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("build.gradle.kts").lines().containsOnlyOnce("    war");
 	}
 
 	@Test
@@ -162,10 +156,9 @@ class GradleKtsProjectGenerationConfigurationTests {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.2.4.RELEASE"));
 		description.setLanguage(new JavaLanguage());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).contains("build.gradle.kts");
-		List<String> lines = projectStructure.readAllLines("build.gradle.kts");
-		assertThat(lines).containsSequence("tasks.withType<Test> {", "    useJUnitPlatform()", "}");
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("build.gradle.kts").lines().containsSequence("tasks.withType<Test> {",
+				"    useJUnitPlatform()", "}");
 	}
 
 	@Test
@@ -173,10 +166,9 @@ class GradleKtsProjectGenerationConfigurationTests {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.1.4.RELEASE"));
 		description.setLanguage(new JavaLanguage());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).contains("build.gradle.kts");
-		List<String> lines = projectStructure.readAllLines("build.gradle.kts");
-		assertThat(lines).doesNotContainSequence("tasks.withType<Test> {", "    useJUnitPlatform()", "}");
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("build.gradle.kts").lines().doesNotContainSequence("tasks.withType<Test> {",
+				"    useJUnitPlatform()", "}");
 	}
 
 }

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/build/gradle/GradleProjectGenerationConfigurationTests.java

@@ -16,10 +16,7 @@
 
 package io.spring.initializr.generator.spring.build.gradle;
 
-import java.io.IOException;
-import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.List;
 import java.util.Map;
 import java.util.stream.Stream;
 
@@ -93,19 +90,15 @@ class GradleProjectGenerationConfigurationTests {
 
 	@ParameterizedTest(name = "Spring Boot {0}")
 	@MethodSource("gradleWrapperParameters")
-	void gradleWrapperIsContributedWhenGeneratingGradleProject(String platformVersion, String expectedGradleVersion)
-			throws IOException {
+	void gradleWrapperIsContributedWhenGeneratingGradleProject(String platformVersion, String expectedGradleVersion) {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse(platformVersion));
 		description.setLanguage(new JavaLanguage());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		List<String> relativePaths = projectStructure.getRelativePathsOfProjectFiles();
-		assertThat(relativePaths).contains("gradlew", "gradlew.bat", "gradle/wrapper/gradle-wrapper.properties",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).containsFiles("gradlew", "gradlew.bat", "gradle/wrapper/gradle-wrapper.properties",
 				"gradle/wrapper/gradle-wrapper.jar");
-		try (Stream<String> lines = Files.lines(projectStructure.resolve("gradle/wrapper/gradle-wrapper.properties"))) {
-			assertThat(lines.filter((line) -> line.contains(String.format("gradle-%s-bin.zip", expectedGradleVersion))))
-					.hasSize(1);
-		}
+		assertThat(project).textFile("gradle/wrapper/gradle-wrapper.properties")
+				.containsOnlyOnce(String.format("gradle-%s-bin.zip", expectedGradleVersion));
 	}
 
 	@Test
@@ -115,11 +108,9 @@ class GradleProjectGenerationConfigurationTests {
 		description.setLanguage(new JavaLanguage("11"));
 		description.addDependency("acme",
 				Dependency.withCoordinates("com.example", "acme").scope(DependencyScope.COMPILE).build());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		List<String> relativePaths = projectStructure.getRelativePathsOfProjectFiles();
-		assertThat(relativePaths).contains("build.gradle");
-		List<String> lines = projectStructure.readAllLines("build.gradle");
-		assertThat(lines).containsExactly("plugins {", "    id 'org.springframework.boot' version '2.1.0.RELEASE'",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("build.gradle").containsExactly("plugins {",
+				"    id 'org.springframework.boot' version '2.1.0.RELEASE'",
 				"    id 'io.spring.dependency-management' version '1.0.6.RELEASE'", "    id 'java'", "}", "",
 				"group = 'com.example'", "version = '0.0.1-SNAPSHOT'", "sourceCompatibility = '11'", "",
 				"repositories {", "    mavenCentral()", "}", "", "dependencies {",
@@ -129,17 +120,13 @@ class GradleProjectGenerationConfigurationTests {
 	}
 
 	@Test
-	void warPluginIsAppliedWhenBuildingProjectThatUsesWarPackaging() throws IOException {
+	void warPluginIsAppliedWhenBuildingProjectThatUsesWarPackaging() {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.1.0.RELEASE"));
 		description.setLanguage(new JavaLanguage());
 		description.setPackaging(new WarPackaging());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		List<String> relativePaths = projectStructure.getRelativePathsOfProjectFiles();
-		assertThat(relativePaths).contains("build.gradle");
-		try (Stream<String> lines = Files.lines(projectStructure.resolve("build.gradle"))) {
-			assertThat(lines.filter((line) -> line.contains("    id 'war'"))).hasSize(1);
-		}
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("build.gradle").lines().containsOnlyOnce("    id 'war'");
 	}
 
 	@Test
@@ -147,10 +134,8 @@ class GradleProjectGenerationConfigurationTests {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.2.4.RELEASE"));
 		description.setLanguage(new JavaLanguage());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).contains("build.gradle");
-		List<String> lines = projectStructure.readAllLines("build.gradle");
-		assertThat(lines).containsSequence("test {", "    useJUnitPlatform()", "}");
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("build.gradle").lines().containsSequence("test {", "    useJUnitPlatform()", "}");
 	}
 
 	@Test
@@ -158,10 +143,9 @@ class GradleProjectGenerationConfigurationTests {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.1.4.RELEASE"));
 		description.setLanguage(new JavaLanguage());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).contains("build.gradle");
-		List<String> lines = projectStructure.readAllLines("build.gradle");
-		assertThat(lines).doesNotContainSequence("test {", "    useJUnitPlatform()", "}");
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("build.gradle").lines().doesNotContainSequence("test {", "    useJUnitPlatform()",
+				"}");
 	}
 
 	@Test
@@ -170,10 +154,8 @@ class GradleProjectGenerationConfigurationTests {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.2.0.M4"));
 		description.setLanguage(new JavaLanguage());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).contains("build.gradle");
-		List<String> lines = projectStructure.readAllLines("build.gradle");
-		assertThat(lines).containsSequence(
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("build.gradle").lines().containsSequence(
 				"    testImplementation('org.springframework.boot:spring-boot-starter-test') {",
 				"        exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'",
 				"        exclude group: 'junit', module: 'junit'", "    }");
@@ -184,10 +166,8 @@ class GradleProjectGenerationConfigurationTests {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.2.0.M5"));
 		description.setLanguage(new JavaLanguage());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).contains("build.gradle");
-		List<String> lines = projectStructure.readAllLines("build.gradle");
-		assertThat(lines).containsSequence(
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("build.gradle").lines().containsSequence(
 				"    testImplementation('org.springframework.boot:spring-boot-starter-test') {",
 				"        exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'", "    }");
 	}
@@ -197,10 +177,8 @@ class GradleProjectGenerationConfigurationTests {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.1.6.RELEASE"));
 		description.setLanguage(new JavaLanguage());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).contains("build.gradle");
-		List<String> lines = projectStructure.readAllLines("build.gradle");
-		assertThat(lines).doesNotContain("exclude group");
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("build.gradle").doesNotContain("exclude group");
 	}
 
 	static Stream<Arguments> annotationProcessorScopeBuildParameters() {

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/build/gradle/SettingsGradleProjectContributorTests.java

@@ -19,19 +19,16 @@ package io.spring.initializr.generator.spring.build.gradle;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.List;
 
 import io.spring.initializr.generator.buildsystem.gradle.GradleBuild;
 import io.spring.initializr.generator.buildsystem.gradle.GroovyDslGradleSettingsWriter;
 import io.spring.initializr.generator.buildsystem.gradle.KotlinDslGradleSettingsWriter;
 import io.spring.initializr.generator.io.IndentingWriterFactory;
 import io.spring.initializr.generator.io.SimpleIndentStrategy;
-import io.spring.initializr.generator.test.project.ProjectStructure;
+import io.spring.initializr.generator.test.io.TextAssert;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.io.TempDir;
 
-import static org.assertj.core.api.Assertions.assertThat;
-
 /**
  * Tests for {@link SettingsGradleProjectContributorTests}.
  *
@@ -47,10 +44,9 @@ class SettingsGradleProjectContributorTests {
 	void groovyDslGradleSettingsIsContributedToProject() throws IOException {
 		GradleBuild build = new GradleBuild();
 		build.pluginRepositories().add("maven-central");
-		List<String> lines = generateSettings(
-				groovyDslSettingsGradleProjectContributor(build, IndentingWriterFactory.withDefaultSettings()));
-		assertThat(lines).containsSequence("pluginManagement {", "    repositories {", "        mavenCentral()",
-				"        gradlePluginPortal()", "    }", "}");
+		assertSettings(groovyDslSettingsGradleProjectContributor(build, IndentingWriterFactory.withDefaultSettings()))
+				.lines().containsSequence("pluginManagement {", "    repositories {", "        mavenCentral()",
+						"        gradlePluginPortal()", "    }", "}");
 	}
 
 	@Test
@@ -59,28 +55,26 @@ class SettingsGradleProjectContributorTests {
 				(factory) -> factory.indentingStrategy("gradle", new SimpleIndentStrategy("  ")));
 		GradleBuild build = new GradleBuild();
 		build.pluginRepositories().add("maven-central");
-		List<String> lines = generateSettings(groovyDslSettingsGradleProjectContributor(build, indentingWriterFactory));
-		assertThat(lines).containsSequence("pluginManagement {", "  repositories {", "    mavenCentral()",
-				"    gradlePluginPortal()", "  }", "}");
+		assertSettings(groovyDslSettingsGradleProjectContributor(build, indentingWriterFactory)).lines()
+				.containsSequence("pluginManagement {", "  repositories {", "    mavenCentral()",
+						"    gradlePluginPortal()", "  }", "}");
 	}
 
 	@Test
 	void groovyDslGradleSettingsDoesNotUseRepositories() throws IOException {
 		GradleBuild build = new GradleBuild();
 		build.repositories().add("maven-central");
-		List<String> lines = generateSettings(
-				groovyDslSettingsGradleProjectContributor(build, IndentingWriterFactory.withDefaultSettings()));
-		assertThat(lines).doesNotContain("pluginManagement");
+		assertSettings(groovyDslSettingsGradleProjectContributor(build, IndentingWriterFactory.withDefaultSettings()))
+				.doesNotContain("pluginManagement");
 	}
 
 	@Test
 	void kotlinDslGradleSettingsIsContributedToProject() throws IOException {
 		GradleBuild build = new GradleBuild();
 		build.pluginRepositories().add("maven-central");
-		List<String> lines = generateSettings(
-				kotlinDslSettingsGradleProjectContributor(build, IndentingWriterFactory.withDefaultSettings()));
-		assertThat(lines).containsSequence("pluginManagement {", "    repositories {", "        mavenCentral()",
-				"        gradlePluginPortal()", "    }", "}");
+		assertSettings(kotlinDslSettingsGradleProjectContributor(build, IndentingWriterFactory.withDefaultSettings()))
+				.lines().containsSequence("pluginManagement {", "    repositories {", "        mavenCentral()",
+						"        gradlePluginPortal()", "    }", "}");
 	}
 
 	@Test
@@ -89,24 +83,23 @@ class SettingsGradleProjectContributorTests {
 				(factory) -> factory.indentingStrategy("gradle", new SimpleIndentStrategy("  ")));
 		GradleBuild build = new GradleBuild();
 		build.pluginRepositories().add("maven-central");
-		List<String> lines = generateSettings(kotlinDslSettingsGradleProjectContributor(build, indentingWriterFactory));
-		assertThat(lines).containsSequence("pluginManagement {", "  repositories {", "    mavenCentral()",
-				"    gradlePluginPortal()", "  }", "}");
+		assertSettings(kotlinDslSettingsGradleProjectContributor(build, indentingWriterFactory)).lines()
+				.containsSequence("pluginManagement {", "  repositories {", "    mavenCentral()",
+						"    gradlePluginPortal()", "  }", "}");
 	}
 
 	@Test
 	void kotlinDslGradleSettingsDoesNotUseRepositories() throws IOException {
 		GradleBuild build = new GradleBuild();
 		build.repositories().add("maven-central");
-		List<String> lines = generateSettings(
-				kotlinDslSettingsGradleProjectContributor(build, IndentingWriterFactory.withDefaultSettings()));
-		assertThat(lines).doesNotContain("pluginManagement");
+		assertSettings(kotlinDslSettingsGradleProjectContributor(build, IndentingWriterFactory.withDefaultSettings()))
+				.doesNotContain("pluginManagement");
 	}
 
-	private List<String> generateSettings(SettingsGradleProjectContributor contributor) throws IOException {
+	private TextAssert assertSettings(SettingsGradleProjectContributor contributor) throws IOException {
 		Path projectDir = Files.createTempDirectory(this.directory, "project-");
 		contributor.contribute(projectDir);
-		return new ProjectStructure(projectDir).readAllLines("test.gradle");
+		return new TextAssert(projectDir.resolve("test.gradle"));
 	}
 
 	private SettingsGradleProjectContributor groovyDslSettingsGradleProjectContributor(GradleBuild build,

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/build/maven/MavenProjectGenerationConfigurationTests.java

@@ -16,9 +16,7 @@
 
 package io.spring.initializr.generator.spring.build.maven;
 
-import java.io.IOException;
 import java.nio.file.Path;
-import java.util.List;
 
 import io.spring.initializr.generator.buildsystem.BuildWriter;
 import io.spring.initializr.generator.buildsystem.maven.MavenBuildSystem;
@@ -70,29 +68,26 @@ class MavenProjectGenerationConfigurationTests {
 	void mavenWrapperIsContributedWhenGeneratingMavenProject() {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.1.0.RELEASE"));
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).contains("mvnw", "mvnw.cmd",
-				".mvn/wrapper/MavenWrapperDownloader.java", ".mvn/wrapper/maven-wrapper.properties",
-				".mvn/wrapper/maven-wrapper.jar");
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).filePaths().contains("mvnw", "mvnw.cmd", ".mvn/wrapper/MavenWrapperDownloader.java",
+				".mvn/wrapper/maven-wrapper.properties", ".mvn/wrapper/maven-wrapper.jar");
 	}
 
 	@Test
 	void mavenPomIsContributedWhenGeneratingMavenProject() {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.1.0.RELEASE"));
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).contains("pom.xml");
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).filePaths().contains("pom.xml");
 	}
 
 	@Test
-	void warPackagingIsUsedWhenBuildingProjectThatUsesWarPackaging() throws IOException {
+	void warPackagingIsUsedWhenBuildingProjectThatUsesWarPackaging() {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.1.0.RELEASE"));
 		description.setPackaging(new WarPackaging());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).contains("pom.xml");
-		List<String> lines = projectStructure.readAllLines("pom.xml");
-		assertThat(lines).containsOnlyOnce("    <packaging>war</packaging>");
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("pom.xml").containsOnlyOnce("    <packaging>war</packaging>");
 	}
 
 	@Test
@@ -101,11 +96,9 @@ class MavenProjectGenerationConfigurationTests {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.2.0.M4"));
 		description.setLanguage(new JavaLanguage());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).contains("pom.xml");
-		List<String> lines = projectStructure.readAllLines("pom.xml");
-		assertThat(lines).containsSequence("            <exclusions>", "                <exclusion>",
-				"                    <groupId>org.junit.vintage</groupId>",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("pom.xml").lines().containsSequence("            <exclusions>",
+				"                <exclusion>", "                    <groupId>org.junit.vintage</groupId>",
 				"                    <artifactId>junit-vintage-engine</artifactId>", "                </exclusion>",
 				"                <exclusion>", "                    <groupId>junit</groupId>",
 				"                    <artifactId>junit</artifactId>", "                </exclusion>",
@@ -117,11 +110,9 @@ class MavenProjectGenerationConfigurationTests {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.2.0.M5"));
 		description.setLanguage(new JavaLanguage());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).contains("pom.xml");
-		List<String> lines = projectStructure.readAllLines("pom.xml");
-		assertThat(lines).containsSequence("            <exclusions>", "                <exclusion>",
-				"                    <groupId>org.junit.vintage</groupId>",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("pom.xml").lines().containsSequence("            <exclusions>",
+				"                <exclusion>", "                    <groupId>org.junit.vintage</groupId>",
 				"                    <artifactId>junit-vintage-engine</artifactId>", "                </exclusion>",
 				"            </exclusions>");
 	}
@@ -131,10 +122,8 @@ class MavenProjectGenerationConfigurationTests {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.1.6.RELEASE"));
 		description.setLanguage(new JavaLanguage());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).contains("pom.xml");
-		List<String> lines = projectStructure.readAllLines("pom.xml");
-		assertThat(lines).doesNotContain("            <exclusions>");
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("pom.xml").doesNotContain("            <exclusions>");
 	}
 
 }

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/code/CodeComplianceTests.java

@@ -26,7 +26,7 @@ import io.spring.initializr.generator.language.java.JavaLanguage;
 import io.spring.initializr.generator.language.kotlin.KotlinLanguage;
 import io.spring.initializr.generator.packaging.Packaging;
 import io.spring.initializr.generator.spring.AbstractComplianceTests;
-import io.spring.initializr.generator.test.project.ProjectAssert;
+import io.spring.initializr.generator.test.project.ProjectStructure;
 import io.spring.initializr.generator.version.Version;
 import io.spring.initializr.metadata.support.MetadataBuildItemMapper;
 import org.junit.jupiter.params.ParameterizedTest;
@@ -35,6 +35,8 @@ import org.junit.jupiter.params.provider.MethodSource;
 
 import org.springframework.core.io.ClassPathResource;
 
+import static org.assertj.core.api.Assertions.assertThat;
+
 /**
  * Code compliance tests.
  *
@@ -52,113 +54,115 @@ class CodeComplianceTests extends AbstractComplianceTests {
 	@ParameterizedTest
 	@MethodSource("parameters")
 	void currentGenerationJar(Language language, String extension) {
-		ProjectAssert project = generateProject(language, maven, "2.1.1.RELEASE");
-		project.isGenericProject(ProjectAssert.DEFAULT_PACKAGE_NAME, ProjectAssert.DEFAULT_APPLICATION_NAME,
-				language.id(), extension);
+		ProjectStructure project = generateProject(language, maven, "2.1.1.RELEASE");
+		assertThat(project).filePaths().contains(
+				String.format("src/main/%s/com/example/demo/DemoApplication.%s", language.id(), extension),
+				String.format("src/test/%s/com/example/demo/DemoApplicationTests.%s", language.id(), extension),
+				"src/main/resources/application.properties");
 	}
 
 	@ParameterizedTest
 	@MethodSource("parameters")
 	void currentGenerationWar(Language language, String extension) {
-		ProjectAssert project = generateProject(language, maven, "2.1.1.RELEASE",
+		ProjectStructure project = generateProject(language, maven, "2.1.1.RELEASE",
 				(description) -> description.setPackaging(Packaging.forId("war")));
-		project.isGenericProject(ProjectAssert.DEFAULT_PACKAGE_NAME, ProjectAssert.DEFAULT_APPLICATION_NAME,
-				language.id(), extension);
+		assertThat(project).filePaths().contains(
+				String.format("src/main/%s/com/example/demo/DemoApplication.%s", language.id(), extension),
+				String.format("src/test/%s/com/example/demo/DemoApplicationTests.%s", language.id(), extension),
+				"src/main/resources/application.properties");
 	}
 
 	@ParameterizedTest
 	@MethodSource("parameters")
 	void currentGenerationMainClass(Language language, String extension) {
-		ProjectAssert project = generateProject(language, maven, "2.1.1.RELEASE");
-		project.sourceCodeAssert("src/main/" + language + "/com/example/demo/DemoApplication." + extension)
-				.equalsTo(new ClassPathResource(
+		ProjectStructure project = generateProject(language, maven, "2.1.1.RELEASE");
+		assertThat(project).asJvmModule(language, extension).mainSource("com.example.demo", "DemoApplication")
+				.hasSameContentAs(new ClassPathResource(
 						"project/" + language + "/standard/DemoApplication." + getExpectedExtension(extension)));
 	}
 
 	@ParameterizedTest
 	@MethodSource("parameters")
 	void previousGenerationMainClass(Language language, String extension) {
-		ProjectAssert project = generateProject(language, maven, "2.1.1.RELEASE",
+		ProjectStructure project = generateProject(language, maven, "2.1.1.RELEASE",
 				(description) -> description.setPlatformVersion(Version.parse("1.5.18.RELEASE")));
-		project.sourceCodeAssert("src/main/" + language + "/com/example/demo/DemoApplication." + extension)
-				.equalsTo(new ClassPathResource(
+		assertThat(project).asJvmModule(language, extension).mainSource("com.example.demo", "DemoApplication")
+				.hasSameContentAs(new ClassPathResource(
 						"project/" + language + "/previous/" + "/DemoApplication." + getExpectedExtension(extension)));
 	}
 
 	@ParameterizedTest
 	@MethodSource("parameters")
 	void currentGenerationTestClass(Language language, String extension) {
-		ProjectAssert project = generateProject(language, maven, "2.1.1.RELEASE");
-		project.sourceCodeAssert("src/test/" + language + "/com/example/demo/DemoApplicationTests." + extension)
-				.equalsTo(new ClassPathResource(
+		ProjectStructure project = generateProject(language, maven, "2.1.1.RELEASE");
+		assertThat(project).asJvmModule(language, extension).testSource("com.example.demo", "DemoApplicationTests")
+				.hasSameContentAs(new ClassPathResource(
 						"project/" + language + "/standard/DemoApplicationTests." + getExpectedExtension(extension)));
 	}
 
 	@ParameterizedTest
 	@MethodSource("parameters")
 	void currentGenerationTestClassWeb(Language language, String extension) {
-		ProjectAssert project = generateProject(language, maven, "2.1.1.RELEASE",
+		ProjectStructure project = generateProject(language, maven, "2.1.1.RELEASE",
 				(description) -> description.addDependency("web", MetadataBuildItemMapper.toDependency(WEB)));
-		project.sourceCodeAssert("src/test/" + language + "/com/example/demo/DemoApplicationTests." + extension)
-				.equalsTo(new ClassPathResource("project/" + language + "/standard/DemoApplicationTestsWeb."
+		assertThat(project).asJvmModule(language, extension).testSource("com.example.demo", "DemoApplicationTests")
+				.hasSameContentAs(new ClassPathResource("project/" + language + "/standard/DemoApplicationTestsWeb."
 						+ getExpectedExtension(extension)));
 	}
 
 	@ParameterizedTest
 	@MethodSource("parameters")
 	void currentGenerationServletInitializer(Language language, String extension) {
-		ProjectAssert project = generateProject(language, maven, "2.1.1.RELEASE",
+		ProjectStructure project = generateProject(language, maven, "2.1.1.RELEASE",
 				(description) -> description.setPackaging(Packaging.forId("war")));
-		project.sourceCodeAssert("src/main/" + language + "/com/example/demo/ServletInitializer." + extension)
-				.equalsTo(new ClassPathResource("project/" + language + "/standard/" + "ServletInitializer."
+		assertThat(project).asJvmModule(language, extension).mainSource("com.example.demo", "ServletInitializer")
+				.hasSameContentAs(new ClassPathResource("project/" + language + "/standard/" + "ServletInitializer."
 						+ getExpectedExtension(extension)));
 	}
 
 	@ParameterizedTest
 	@MethodSource("parameters")
 	void previousGenerationServletInitializer(Language language, String extension) {
-		ProjectAssert project = generateProject(language, maven, "2.1.1.RELEASE", (description) -> {
+		ProjectStructure project = generateProject(language, maven, "2.1.1.RELEASE", (description) -> {
 			description.setPackaging(Packaging.forId("war"));
 			description.setPlatformVersion(Version.parse("1.5.18.RELEASE"));
 		});
-		project.sourceCodeAssert("src/main/" + language + "/com/example/demo/ServletInitializer." + extension)
-				.equalsTo(new ClassPathResource("project/" + language + "/previous/" + "ServletInitializer."
+		assertThat(project).asJvmModule(language, extension).mainSource("com.example.demo", "ServletInitializer")
+				.hasSameContentAs(new ClassPathResource("project/" + language + "/previous/" + "ServletInitializer."
 						+ getExpectedExtension(extension)));
 	}
 
 	@ParameterizedTest
 	@MethodSource("parameters")
 	void currentGenerationCustomCoordinates(Language language, String extension) {
-		ProjectAssert project = generateProject(language, maven, "2.1.1.RELEASE", (description) -> {
+		ProjectStructure project = generateProject(language, maven, "2.1.1.RELEASE", (description) -> {
 			description.setGroupId("com.example.acme");
 			description.setArtifactId("my-project");
 			description.setPackageName("com.example.acme.myproject");
 			description.setApplicationName("MyProjectApplication");
 		});
-		project.isGenericProject("com.example.acme.myproject", "MyProjectApplication", language.id(), extension);
-		project.sourceCodeAssert(
-				"src/main/" + language + "/com/example/acme/myproject/MyProjectApplication." + extension)
-				.equalsTo(new ClassPathResource(
+		assertThat(project).asJvmModule(language, extension)
+				.mainSource("com.example.acme.myproject", "MyProjectApplication")
+				.hasSameContentAs(new ClassPathResource(
 						"project/" + language + "/standard/MyProjectApplication." + getExpectedExtension(extension)));
-		project.sourceCodeAssert(
-				"src/test/" + language + "/com/example/acme/myproject/MyProjectApplicationTests." + extension)
-				.equalsTo(new ClassPathResource("project/" + language + "/standard/MyProjectApplicationTests."
+		assertThat(project).asJvmModule(language, extension)
+				.testSource("com.example.acme.myproject", "MyProjectApplicationTests")
+				.hasSameContentAs(new ClassPathResource("project/" + language + "/standard/MyProjectApplicationTests."
 						+ getExpectedExtension(extension)));
 	}
 
 	@ParameterizedTest
 	@MethodSource("parameters")
 	void previousGenerationCustomCoordinates(Language language, String extension) {
-		ProjectAssert project = generateProject(language, maven, "1.5.18.RELEASE", (description) -> {
+		ProjectStructure project = generateProject(language, maven, "1.5.18.RELEASE", (description) -> {
 			description.setGroupId("com.example.acme");
 			description.setArtifactId("my-project");
 			description.setPackageName("com.example.acme.myproject");
 			description.setApplicationName("MyProjectApplication");
 		});
-		project.isGenericProject("com.example.acme.myproject", "MyProjectApplication", language.id(), extension);
-		project.sourceCodeAssert(
-				"src/main/" + language + "/com/example/acme/myproject/MyProjectApplication." + extension)
-				.equalsTo(new ClassPathResource(
+		assertThat(project).asJvmModule(language, extension)
+				.mainSource("com.example.acme.myproject", "MyProjectApplication")
+				.hasSameContentAs(new ClassPathResource(
 						"project/" + language + "/previous/MyProjectApplication." + getExpectedExtension(extension)));
 	}
 

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/code/groovy/GroovyProjectGenerationConfigurationTests.java

@@ -17,7 +17,6 @@
 package io.spring.initializr.generator.spring.code.groovy;
 
 import java.nio.file.Path;
-import java.util.List;
 
 import io.spring.initializr.generator.buildsystem.maven.MavenBuildSystem;
 import io.spring.initializr.generator.language.groovy.GroovyLanguage;
@@ -58,22 +57,18 @@ class GroovyProjectGenerationConfigurationTests {
 
 	@Test
 	void mainClassIsContributed() {
-		ProjectStructure projectStructure = this.projectTester.generate(new ProjectDescription());
-		assertThat(projectStructure.getRelativePathsOfProjectFiles())
-				.contains("src/main/groovy/com/example/demo/DemoApplication.groovy");
+		ProjectStructure project = this.projectTester.generate(new ProjectDescription());
+		assertThat(project).containsFiles("src/main/groovy/com/example/demo/DemoApplication.groovy");
 	}
 
 	@Test
 	void testClassIsContributedWithJUnit4() {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.1.4.RELEASE"));
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles())
-				.contains("src/test/groovy/com/example/demo/DemoApplicationTests.groovy");
-		List<String> lines = projectStructure
-				.readAllLines("src/test/groovy/com/example/demo/DemoApplicationTests.groovy");
-		assertThat(lines).containsExactly("package com.example.demo", "", "import org.junit.Test",
-				"import org.junit.runner.RunWith", "import org.springframework.boot.test.context.SpringBootTest",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("src/test/groovy/com/example/demo/DemoApplicationTests.groovy").containsExactly(
+				"package com.example.demo", "", "import org.junit.Test", "import org.junit.runner.RunWith",
+				"import org.springframework.boot.test.context.SpringBootTest",
 				"import org.springframework.test.context.junit4.SpringRunner", "", "@RunWith(SpringRunner)",
 				"@SpringBootTest", "class DemoApplicationTests {", "", "    @Test", "    void contextLoads() {",
 				"    }", "", "}");
@@ -83,12 +78,9 @@ class GroovyProjectGenerationConfigurationTests {
 	void testClassIsContributedWithJUnit5() {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.2.0.RELEASE"));
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles())
-				.contains("src/test/groovy/com/example/demo/DemoApplicationTests.groovy");
-		List<String> lines = projectStructure
-				.readAllLines("src/test/groovy/com/example/demo/DemoApplicationTests.groovy");
-		assertThat(lines).containsExactly("package com.example.demo", "", "import org.junit.jupiter.api.Test",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("src/test/groovy/com/example/demo/DemoApplicationTests.groovy").containsExactly(
+				"package com.example.demo", "", "import org.junit.jupiter.api.Test",
 				"import org.springframework.boot.test.context.SpringBootTest", "", "@SpringBootTest",
 				"class DemoApplicationTests {", "", "    @Test", "    void contextLoads() {", "    }", "", "}");
 	}
@@ -98,13 +90,9 @@ class GroovyProjectGenerationConfigurationTests {
 		ProjectDescription description = new ProjectDescription();
 		description.setPackaging(new WarPackaging());
 		description.setApplicationName("Demo2Application");
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles())
-				.contains("src/main/groovy/com/example/demo/ServletInitializer.groovy");
-		List<String> lines = projectStructure
-				.readAllLines("src/main/groovy/com/example/demo/ServletInitializer.groovy");
-		assertThat(lines).containsExactly("package com.example.demo", "",
-				"import org.springframework.boot.builder.SpringApplicationBuilder",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("src/main/groovy/com/example/demo/ServletInitializer.groovy").containsExactly(
+				"package com.example.demo", "", "import org.springframework.boot.builder.SpringApplicationBuilder",
 				"import org.springframework.boot.web.servlet.support.SpringBootServletInitializer", "",
 				"class ServletInitializer extends SpringBootServletInitializer {", "", "    @Override",
 				"    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {",

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/code/java/JavaProjectGenerationConfigurationTests.java

@@ -17,7 +17,6 @@
 package io.spring.initializr.generator.spring.code.java;
 
 import java.nio.file.Path;
-import java.util.List;
 
 import io.spring.initializr.generator.buildsystem.maven.MavenBuildSystem;
 import io.spring.initializr.generator.language.java.JavaLanguage;
@@ -59,21 +58,18 @@ class JavaProjectGenerationConfigurationTests {
 	@Test
 	void mainClassIsContributed() {
 		ProjectDescription description = new ProjectDescription();
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles())
-				.contains("src/main/java/com/example/demo/DemoApplication.java");
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).containsFiles("src/main/java/com/example/demo/DemoApplication.java");
 	}
 
 	@Test
 	void testClassIsContributedWithJUnit4() {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.1.4.RELEASE"));
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles())
-				.contains("src/test/java/com/example/demo/DemoApplicationTests.java");
-		List<String> lines = projectStructure.readAllLines("src/test/java/com/example/demo/DemoApplicationTests.java");
-		assertThat(lines).containsExactly("package com.example.demo;", "", "import org.junit.Test;",
-				"import org.junit.runner.RunWith;", "import org.springframework.boot.test.context.SpringBootTest;",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("src/test/java/com/example/demo/DemoApplicationTests.java").containsExactly(
+				"package com.example.demo;", "", "import org.junit.Test;", "import org.junit.runner.RunWith;",
+				"import org.springframework.boot.test.context.SpringBootTest;",
 				"import org.springframework.test.context.junit4.SpringRunner;", "", "@RunWith(SpringRunner.class)",
 				"@SpringBootTest", "public class DemoApplicationTests {", "", "    @Test",
 				"    public void contextLoads() {", "    }", "", "}");
@@ -83,11 +79,9 @@ class JavaProjectGenerationConfigurationTests {
 	void testClassIsContributedWithJUnit5() {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.2.0.RELEASE"));
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles())
-				.contains("src/test/java/com/example/demo/DemoApplicationTests.java");
-		List<String> lines = projectStructure.readAllLines("src/test/java/com/example/demo/DemoApplicationTests.java");
-		assertThat(lines).containsExactly("package com.example.demo;", "", "import org.junit.jupiter.api.Test;",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("src/test/java/com/example/demo/DemoApplicationTests.java").containsExactly(
+				"package com.example.demo;", "", "import org.junit.jupiter.api.Test;",
 				"import org.springframework.boot.test.context.SpringBootTest;", "", "@SpringBootTest",
 				"class DemoApplicationTests {", "", "    @Test", "    void contextLoads() {", "    }", "", "}");
 	}
@@ -97,12 +91,9 @@ class JavaProjectGenerationConfigurationTests {
 		ProjectDescription description = new ProjectDescription();
 		description.setPackaging(new WarPackaging());
 		description.setApplicationName("MyDemoApplication");
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles())
-				.contains("src/main/java/com/example/demo/ServletInitializer.java");
-		List<String> lines = projectStructure.readAllLines("src/main/java/com/example/demo/ServletInitializer.java");
-		assertThat(lines).containsExactly("package com.example.demo;", "",
-				"import org.springframework.boot.builder.SpringApplicationBuilder;",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("src/main/java/com/example/demo/ServletInitializer.java").containsExactly(
+				"package com.example.demo;", "", "import org.springframework.boot.builder.SpringApplicationBuilder;",
 				"import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;", "",
 				"public class ServletInitializer extends SpringBootServletInitializer {", "", "    @Override",
 				"    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {",
@@ -113,9 +104,8 @@ class JavaProjectGenerationConfigurationTests {
 	void customPackageNameIsUsedWhenGeneratingProject() {
 		ProjectDescription description = new ProjectDescription();
 		description.setPackageName("com.example.foo");
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).contains(
-				"src/main/java/com/example/foo/DemoApplication.java",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).containsFiles("src/main/java/com/example/foo/DemoApplication.java",
 				"src/test/java/com/example/foo/DemoApplicationTests.java");
 	}
 
@@ -123,9 +113,8 @@ class JavaProjectGenerationConfigurationTests {
 	void customApplicationNameIsUsedWhenGeneratingProject() {
 		ProjectDescription description = new ProjectDescription();
 		description.setApplicationName("MyApplication");
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).contains(
-				"src/main/java/com/example/demo/MyApplication.java",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).containsFiles("src/main/java/com/example/demo/MyApplication.java",
 				"src/test/java/com/example/demo/MyApplicationTests.java");
 	}
 

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/code/kotlin/KotlinProjectGenerationConfigurationTests.java

@@ -18,7 +18,6 @@ package io.spring.initializr.generator.spring.code.kotlin;
 
 import java.nio.file.Path;
 import java.util.Collections;
-import java.util.List;
 
 import io.spring.initializr.generator.buildsystem.Dependency;
 import io.spring.initializr.generator.buildsystem.maven.MavenBuildSystem;
@@ -85,21 +84,18 @@ class KotlinProjectGenerationConfigurationTests {
 
 	@Test
 	void mainClassIsContributedWhenGeneratingProject() {
-		ProjectStructure projectStructure = this.projectTester.generate(new ProjectDescription());
-		assertThat(projectStructure.getRelativePathsOfProjectFiles())
-				.contains("src/main/kotlin/com/example/demo/DemoApplication.kt");
+		ProjectStructure project = this.projectTester.generate(new ProjectDescription());
+		assertThat(project).containsFiles("src/main/kotlin/com/example/demo/DemoApplication.kt");
 	}
 
 	@Test
 	void testClassIsContributedWithJunit4() {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.1.4.RELEASE"));
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles())
-				.contains("src/test/kotlin/com/example/demo/DemoApplicationTests.kt");
-		List<String> lines = projectStructure.readAllLines("src/test/kotlin/com/example/demo/DemoApplicationTests.kt");
-		assertThat(lines).containsExactly("package com.example.demo", "", "import org.junit.Test",
-				"import org.junit.runner.RunWith", "import org.springframework.boot.test.context.SpringBootTest",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("src/test/kotlin/com/example/demo/DemoApplicationTests.kt").containsExactly(
+				"package com.example.demo", "", "import org.junit.Test", "import org.junit.runner.RunWith",
+				"import org.springframework.boot.test.context.SpringBootTest",
 				"import org.springframework.test.context.junit4.SpringRunner", "", "@RunWith(SpringRunner::class)",
 				"@SpringBootTest", "class DemoApplicationTests {", "", "    @Test", "    fun contextLoads() {", "    }",
 				"", "}");
@@ -109,11 +105,9 @@ class KotlinProjectGenerationConfigurationTests {
 	void testClassIsContributedWithJunit5() {
 		ProjectDescription description = new ProjectDescription();
 		description.setPlatformVersion(Version.parse("2.2.0.RELEASE"));
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles())
-				.contains("src/test/kotlin/com/example/demo/DemoApplicationTests.kt");
-		List<String> lines = projectStructure.readAllLines("src/test/kotlin/com/example/demo/DemoApplicationTests.kt");
-		assertThat(lines).containsExactly("package com.example.demo", "", "import org.junit.jupiter.api.Test",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("src/test/kotlin/com/example/demo/DemoApplicationTests.kt").containsExactly(
+				"package com.example.demo", "", "import org.junit.jupiter.api.Test",
 				"import org.springframework.boot.test.context.SpringBootTest", "", "@SpringBootTest",
 				"class DemoApplicationTests {", "", "    @Test", "    fun contextLoads() {", "    }", "", "}");
 	}
@@ -123,12 +117,9 @@ class KotlinProjectGenerationConfigurationTests {
 		ProjectDescription description = new ProjectDescription();
 		description.setPackaging(new WarPackaging());
 		description.setApplicationName("KotlinDemoApplication");
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles())
-				.contains("src/main/kotlin/com/example/demo/ServletInitializer.kt");
-		List<String> lines = projectStructure.readAllLines("src/main/kotlin/com/example/demo/ServletInitializer.kt");
-		assertThat(lines).containsExactly("package com.example.demo", "",
-				"import org.springframework.boot.builder.SpringApplicationBuilder",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("src/main/kotlin/com/example/demo/ServletInitializer.kt").containsExactly(
+				"package com.example.demo", "", "import org.springframework.boot.builder.SpringApplicationBuilder",
 				"import org.springframework.boot.web.servlet.support.SpringBootServletInitializer", "",
 				"class ServletInitializer : SpringBootServletInitializer() {", "",
 				"    override fun configure(application: SpringApplicationBuilder): SpringApplicationBuilder {",
@@ -139,9 +130,8 @@ class KotlinProjectGenerationConfigurationTests {
 	void jacksonKotlinModuleShouldBeAddedWhenJsonFacetPresent() {
 		ProjectDescription description = new ProjectDescription();
 		description.addDependency("foo", Dependency.withCoordinates("com.example", "foo").build());
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		List<String> lines = projectStructure.readAllLines("pom.xml");
-		assertThat(lines).contains("        <dependency>",
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).textFile("pom.xml").contains("        <dependency>",
 				"            <groupId>com.fasterxml.jackson.module</groupId>",
 				"            <artifactId>jackson-module-kotlin</artifactId>", "        </dependency>");
 	}

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/configuration/ApplicationPropertiesContributorTests.java

@@ -19,7 +19,6 @@ package io.spring.initializr.generator.spring.configuration;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.List;
 
 import io.spring.initializr.generator.test.project.ProjectStructure;
 import org.junit.jupiter.api.Test;
@@ -41,8 +40,8 @@ class ApplicationPropertiesContributorTests {
 	void applicationConfigurationWithDefaultSettings() throws IOException {
 		Path projectDir = Files.createTempDirectory(this.directory, "project-");
 		new ApplicationPropertiesContributor().contribute(projectDir);
-		List<String> lines = new ProjectStructure(projectDir).readAllLines("src/main/resources/application.properties");
-		assertThat(lines).isEmpty();
+		assertThat(new ProjectStructure(projectDir)).textFile("src/main/resources/application.properties").lines()
+				.isEmpty();
 	}
 
 }

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/documentation/HelpDocumentProjectContributorTests.java

@@ -19,10 +19,10 @@ package io.spring.initializr.generator.spring.documentation;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.List;
 
 import io.spring.initializr.generator.io.template.MustacheTemplateRenderer;
-import io.spring.initializr.generator.test.project.ProjectStructure;
+import io.spring.initializr.generator.test.io.TextAssert;
+import org.assertj.core.api.ListAssert;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.io.TempDir;
@@ -61,8 +61,7 @@ class HelpDocumentProjectContributorTests {
 		HelpDocument document = new HelpDocument(this.templateRenderer);
 		document.gettingStarted().addGuideLink("https://test.example.com", "test")
 				.addGuideLink("https://test2.example.com", "test2");
-		List<String> lines = generateDocument(document);
-		assertThat(lines).containsExactly("# Getting Started", "", "### Guides",
+		assertHelpDocument(document).containsExactly("# Getting Started", "", "### Guides",
 				"The following guides illustrate how to use some features concretely:", "",
 				"* [test](https://test.example.com)", "* [test2](https://test2.example.com)");
 	}
@@ -72,8 +71,7 @@ class HelpDocumentProjectContributorTests {
 		HelpDocument document = new HelpDocument(this.templateRenderer);
 		document.gettingStarted().addReferenceDocLink("https://test.example.com", "doc")
 				.addReferenceDocLink("https://test2.example.com", "doc2");
-		List<String> lines = generateDocument(document);
-		assertThat(lines).containsExactly("# Getting Started", "", "### Reference Documentation",
+		assertHelpDocument(document).containsExactly("# Getting Started", "", "### Reference Documentation",
 				"For further reference, please consider the following sections:", "",
 				"* [doc](https://test.example.com)", "* [doc2](https://test2.example.com)");
 	}
@@ -82,8 +80,7 @@ class HelpDocumentProjectContributorTests {
 	void helpDocumentWithLinksToOtherLinks() throws IOException {
 		HelpDocument document = new HelpDocument(this.templateRenderer);
 		document.gettingStarted().addAdditionalLink("https://test.example.com", "Something");
-		List<String> lines = generateDocument(document);
-		assertThat(lines).containsExactly("# Getting Started", "", "### Additional Links",
+		assertHelpDocument(document).containsExactly("# Getting Started", "", "### Additional Links",
 				"These additional references should also help you:", "", "* [Something](https://test.example.com)");
 	}
 
@@ -91,8 +88,7 @@ class HelpDocumentProjectContributorTests {
 	void helpDocumentWithSimpleSection() throws IOException {
 		HelpDocument document = new HelpDocument(this.templateRenderer);
 		document.addSection((writer) -> writer.println(String.format("# My test section%n%n    * Test")));
-		List<String> lines = generateDocument(document);
-		assertThat(lines).containsExactly("# My test section", "", "    * Test");
+		assertHelpDocument(document).containsExactly("# My test section", "", "    * Test");
 	}
 
 	@Test
@@ -100,16 +96,15 @@ class HelpDocumentProjectContributorTests {
 		HelpDocument document = new HelpDocument(this.templateRenderer);
 		document.gettingStarted().addGuideLink("https://test.example.com", "test")
 				.addSection((writer) -> writer.println(String.format("# My test section%n%n    * Test")));
-		List<String> lines = generateDocument(document);
-		assertThat(lines).containsExactly("# Getting Started", "", "### Guides",
+		assertHelpDocument(document).containsExactly("# Getting Started", "", "### Guides",
 				"The following guides illustrate how to use some features concretely:", "",
 				"* [test](https://test.example.com)", "", "# My test section", "", "    * Test");
 	}
 
-	private List<String> generateDocument(HelpDocument document) throws IOException {
+	private ListAssert<String> assertHelpDocument(HelpDocument document) throws IOException {
 		Path projectDir = Files.createTempDirectory(this.directory, "project-");
 		new HelpDocumentProjectContributor(document).contribute(projectDir);
-		return new ProjectStructure(projectDir).readAllLines("HELP.md");
+		return new TextAssert(projectDir.resolve("HELP.md")).lines();
 	}
 
 }

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/documentation/HelpDocumentProjectGenerationConfigurationTests.java

@@ -54,7 +54,8 @@ class HelpDocumentProjectGenerationConfigurationTests {
 
 	@Test
 	void helpDocumentIsNotContributedWithoutLinks() {
-		assertThat(this.projectTester.generate(new ProjectDescription()).getRelativePathsOfProjectFiles()).isEmpty();
+		ProjectStructure project = this.projectTester.generate(new ProjectDescription());
+		assertThat(project).filePaths().isEmpty();
 	}
 
 	@Test
@@ -65,8 +66,8 @@ class HelpDocumentProjectGenerationConfigurationTests {
 		this.metadataBuilder.addDependencyGroup("test", dependency);
 		ProjectDescription description = new ProjectDescription();
 		description.addDependency("example", null);
-		ProjectStructure projectStructure = this.projectTester.generate(description);
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).containsOnly("HELP.md");
+		ProjectStructure project = this.projectTester.generate(description);
+		assertThat(project).filePaths().containsOnly("HELP.md");
 	}
 
 	@Test

initializr-generator-test/pom.xml

@@ -24,18 +24,18 @@
 			<groupId>io.spring.initializr</groupId>
 			<artifactId>initializr-metadata</artifactId>
 		</dependency>
-		
+
+		<dependency>
+			<groupId>org.assertj</groupId>
+			<artifactId>assertj-core</artifactId>
+		</dependency>
+
 		<dependency>
 			<groupId>com.samskivert</groupId>
 			<artifactId>jmustache</artifactId>
 			<optional>true</optional>
 		</dependency>
-		<dependency>
-			<groupId>org.assertj</groupId>
-			<artifactId>assertj-core</artifactId>
-			<optional>true</optional>
-		</dependency>
-		
+
 		<dependency>
 			<groupId>org.springframework</groupId>
 			<artifactId>spring-test</artifactId>

initializr-generator-test/src/main/java/io/spring/initializr/generator/test/buildsystem/gradle/GradleBuildAssert.java

@@ -1,106 +0,0 @@
-/*
- * Copyright 2012-2019 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package io.spring.initializr.generator.test.buildsystem.gradle;
-
-import org.assertj.core.api.AbstractStringAssert;
-
-/**
- * Very simple assertions for the gradle build.
- *
- * @author Stephane Nicoll
- */
-public class GradleBuildAssert extends AbstractStringAssert<GradleBuildAssert> {
-
-	public GradleBuildAssert(String content) {
-		super(content, GradleBuildAssert.class);
-	}
-
-	/**
-	 * Assert {@code build.gradle} uses the specified {@code version}.
-	 * @param version the version of the build
-	 * @return this
-	 */
-	public GradleBuildAssert hasVersion(String version) {
-		return contains("version = '" + version + "'");
-	}
-
-	/**
-	 * Assert {@code build.gradle} uses an ext build script block declaring the Spring
-	 * Boot plugin with the specified version.
-	 * @param springBootVersion the spring boot version
-	 * @return this
-	 */
-	public GradleBuildAssert hasSpringBootBuildScriptPlugin(String springBootVersion) {
-		return contains("ext {").contains("org.springframework.boot:spring-boot-gradle-plugin:" + springBootVersion);
-	}
-
-	/**
-	 * Assert {@code build.gradle} declares the Spring Boot plugin with the specified
-	 * version.
-	 * @param springBootVersion the spring boot version
-	 * @return this
-	 */
-	public GradleBuildAssert hasSpringBootPlugin(String springBootVersion) {
-		return contains("id 'org.springframework.boot' version '" + springBootVersion + "'");
-	}
-
-	/**
-	 * Assert {@code build.gradle} declares a source compatibility for the specified java
-	 * version.
-	 * @param javaVersion the java version
-	 * @return this
-	 */
-	public GradleBuildAssert hasJavaVersion(String javaVersion) {
-		return contains("sourceCompatibility = '" + javaVersion + "'");
-	}
-
-	/**
-	 * Assert {@code build.gradle} declares the {@code repo.spring.io/snapshot}
-	 * repository.
-	 * @return this
-	 */
-	public GradleBuildAssert hasSnapshotRepository() {
-		return contains("https://repo.spring.io/snapshot");
-	}
-
-	/**
-	 * Assert {@code build.gradle} declares a repository with the specified url.
-	 * @param url the url of the repository
-	 * @return this
-	 */
-	public GradleBuildAssert hasRepository(String url) {
-		return contains("maven { url '" + url + "' }");
-	}
-
-	/**
-	 * Assert {@code build.gradle} contains only the specified properties.
-	 * @param values the property value pairs
-	 * @return this for method chaining.
-	 */
-	public GradleBuildAssert hasProperties(String... values) {
-		StringBuilder builder = new StringBuilder(String.format("ext {%n"));
-		if (values.length % 2 == 1) {
-			throw new IllegalArgumentException("Size must be even, it is a set of property=value pairs");
-		}
-		for (int i = 0; i < values.length; i += 2) {
-			builder.append(String.format("\tset('%s', \"%s\")%n", values[i], values[i + 1]));
-		}
-		builder.append("}");
-		return contains(builder.toString());
-	}
-
-}

initializr-generator-test/src/main/java/io/spring/initializr/generator/test/buildsystem/gradle/GroovyDslGradleBuildAssert.java

@@ -0,0 +1,105 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.generator.test.buildsystem.gradle;
+
+import java.nio.file.Path;
+
+import io.spring.initializr.generator.test.io.AbstractTextAssert;
+import io.spring.initializr.generator.test.io.TextTestUtils;
+
+/**
+ * Simple assertions for a gradle build using the Groovy DSL.
+ *
+ * @author Stephane Nicoll
+ */
+public class GroovyDslGradleBuildAssert extends AbstractTextAssert<GroovyDslGradleBuildAssert> {
+
+	public GroovyDslGradleBuildAssert(String content) {
+		super(content, GroovyDslGradleBuildAssert.class);
+	}
+
+	public GroovyDslGradleBuildAssert(Path buildGradleFile) {
+		this(TextTestUtils.readContent(buildGradleFile));
+	}
+
+	/**
+	 * Assert {@code build.gradle} defines a plugin with the specified id and version.
+	 * @param id the id of the plugin
+	 * @param version the version of the plugin
+	 * @return {@code this} assertion object
+	 */
+	public GroovyDslGradleBuildAssert hasPlugin(String id, String version) {
+		return contains(String.format("id '%s' version '%s'", id, version));
+	}
+
+	/**
+	 * Assert {@code build.gradle} defines a plugin with the specified id.
+	 * @param id the id of the plugin
+	 * @return {@code this} assertion object
+	 */
+	public GroovyDslGradleBuildAssert hasPlugin(String id) {
+		return contains(String.format("id '%s'", id));
+	}
+
+	/**
+	 * Assert {@code build.gradle} uses the specified {@code version}.
+	 * @param version the version of the build
+	 * @return {@code this} assertion object
+	 */
+	public GroovyDslGradleBuildAssert hasVersion(String version) {
+		return hasProperty("version", version);
+	}
+
+	/**
+	 * Assert {@code build.gradle} uses a source compatibility for the specified java
+	 * version.
+	 * @param javaVersion the java version
+	 * @return {@code this} assertion object
+	 */
+	public GroovyDslGradleBuildAssert hasSourceCompatibility(String javaVersion) {
+		return hasProperty("sourceCompatibility", javaVersion);
+	}
+
+	/**
+	 * Assert {@code build.gradle} defines a top-level property with the specified name
+	 * and value.
+	 * @param name the name of the property
+	 * @param value the value
+	 * @return {@code this} assertion object
+	 */
+	public GroovyDslGradleBuildAssert hasProperty(String name, String value) {
+		return contains(String.format("%s = '%s", name, value));
+	}
+
+	/**
+	 * Assert {@code build.gradle} contains only the specified properties.
+	 * @param values the property value pairs
+	 * @return this for method chaining.
+	 */
+	public GroovyDslGradleBuildAssert containsOnlyExtProperties(String... values) {
+		StringBuilder builder = new StringBuilder(String.format("ext {%n"));
+		if (values.length % 2 == 1) {
+			throw new IllegalArgumentException("Size must be even, it is a set of property=value pairs");
+		}
+		for (int i = 0; i < values.length; i += 2) {
+			builder.append(String.format("\tset('%s', \"%s\")%n", values[i], values[i + 1]));
+		}
+		builder.append("}");
+		return contains(builder.toString());
+	}
+
+}

initializr-generator-test/src/main/java/io/spring/initializr/generator/test/buildsystem/gradle/GroovyDslGradleSettingsAssert.java

@@ -16,38 +16,37 @@
 
 package io.spring.initializr.generator.test.buildsystem.gradle;
 
-import static org.assertj.core.api.Assertions.assertThat;
+import io.spring.initializr.generator.test.io.AbstractTextAssert;
 
 /**
- * Very simple assertions for the gradle settings.
+ * Simple assertions for a gradle settings using the Groovy DSL.
  *
  * @author Stephane Nicoll
  */
-public class GradleSettingsAssert {
+public class GroovyDslGradleSettingsAssert extends AbstractTextAssert<GroovyDslGradleSettingsAssert> {
 
-	private final String content;
-
-	public GradleSettingsAssert(String content) {
-		this.content = content;
+	public GroovyDslGradleSettingsAssert(String content) {
+		super(content, GroovyDslGradleSettingsAssert.class);
 	}
 
 	/**
 	 * Assert {@code settings.gradle} defines the specified project name.
 	 * @param name the name of the project
-	 * @return this
+	 * @return {@code this} assertion object
 	 */
-	public GradleSettingsAssert hasProjectName(String name) {
-		return contains(String.format("rootProject.name = '%s'", name));
+	public GroovyDslGradleSettingsAssert hasProjectName(String name) {
+		return hasProperty("rootProject.name", name);
 	}
 
 	/**
-	 * Assert {@code settings.gradle} contains the specified expression.
-	 * @param expression an expected expression
-	 * @return this
+	 * Assert {@code settings.gradle} defines a property with the specified name and
+	 * value.
+	 * @param name the name of the property
+	 * @param value the value
+	 * @return {@code this} assertion object
 	 */
-	public GradleSettingsAssert contains(String expression) {
-		assertThat(this.content).contains(expression);
-		return this;
+	public GroovyDslGradleSettingsAssert hasProperty(String name, String value) {
+		return contains(String.format("%s = '%s", name, value));
 	}
 
 }

initializr-generator-test/src/main/java/io/spring/initializr/generator/test/buildsystem/maven/MavenBuildAssert.java

@@ -18,107 +18,104 @@ package io.spring.initializr.generator.test.buildsystem.maven;
 
 import java.net.MalformedURLException;
 import java.net.URL;
+import java.nio.file.Path;
 
+import io.spring.initializr.generator.test.io.AbstractTextAssert;
 import io.spring.initializr.generator.test.io.NodeAssert;
+import io.spring.initializr.generator.test.io.TextTestUtils;
 import io.spring.initializr.metadata.BillOfMaterials;
 import io.spring.initializr.metadata.Dependency;
 import io.spring.initializr.metadata.Repository;
+import org.assertj.core.api.BooleanAssert;
 import org.assertj.core.api.Condition;
+import org.assertj.core.api.StringAssert;
+import org.assertj.core.api.UrlAssert;
 import org.w3c.dom.DOMException;
 import org.w3c.dom.Element;
 import org.w3c.dom.Node;
 import org.w3c.dom.NodeList;
 
-import static org.assertj.core.api.Assertions.assertThat;
-
 /**
- * {@link Node} assertions that are specific to a standard Maven POM.
+ * Assertions for a Maven build.
  *
  * @author Stephane Nicoll
  */
-public class PomAssert {
-
-	private final String content;
+public class MavenBuildAssert extends AbstractTextAssert<MavenBuildAssert> {
 
 	private final NodeAssert pom;
 
-	public PomAssert(String content) {
-		this.content = content;
+	public MavenBuildAssert(String content) {
+		super(content, MavenBuildAssert.class);
 		this.pom = new NodeAssert(content);
 	}
 
+	public MavenBuildAssert(Path pomFile) {
+		this(TextTestUtils.readContent(pomFile));
+	}
+
 	/**
 	 * Assert {@code pom.xml} defines the specified parent.
 	 * @param groupId the groupId of the parent
 	 * @param artifactId the artifactId of the parent
 	 * @param version the version of the parent
-	 * @return this
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert hasParent(String groupId, String artifactId, String version) {
+	public MavenBuildAssert hasParent(String groupId, String artifactId, String version) {
 		return hasText("/project/parent/groupId", groupId).hasText("/project/parent/artifactId", artifactId)
 				.hasText("/project/parent/version", version);
 	}
 
-	/**
-	 * Assert {@code pom.xml} defines the standard {@code spring-boot-starter-parent}.
-	 * @param version the spring boot version
-	 * @return this
-	 */
-	public PomAssert hasSpringBootParent(String version) {
-		return hasParent("org.springframework.boot", "spring-boot-starter-parent", version);
-	}
-
 	/**
 	 * Assert {@code pom.xml} uses the specified {@code groupId}.
 	 * @param groupId the groupId of the project
-	 * @return this
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert hasGroupId(String groupId) {
+	public MavenBuildAssert hasGroupId(String groupId) {
 		return hasText("/project/groupId", groupId);
 	}
 
 	/**
 	 * Assert {@code pom.xml} uses the specified {@code artifactId}.
 	 * @param artifactId the artifactId of the project
-	 * @return this
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert hasArtifactId(String artifactId) {
+	public MavenBuildAssert hasArtifactId(String artifactId) {
 		return hasText("/project/artifactId", artifactId);
 	}
 
 	/**
 	 * Assert {@code pom.xml} uses the specified {@code version}.
 	 * @param version the version of the project
-	 * @return this
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert hasVersion(String version) {
+	public MavenBuildAssert hasVersion(String version) {
 		return hasText("/project/version", version);
 	}
 
 	/**
 	 * Assert {@code pom.xml} uses the specified {@code packaging}.
 	 * @param packaging the packaging of the project
-	 * @return this
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert hasPackaging(String packaging) {
+	public MavenBuildAssert hasPackaging(String packaging) {
 		return hasText("/project/packaging", packaging);
 	}
 
 	/**
 	 * Assert {@code pom.xml} uses the specified {@code name}.
 	 * @param name the name of the project
-	 * @return this
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert hasName(String name) {
+	public MavenBuildAssert hasName(String name) {
 		return hasText("/project/name", name);
 	}
 
 	/**
 	 * Assert {@code pom.xml} uses the specified {@code description}.
 	 * @param description the description of the project
-	 * @return this
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert hasDescription(String description) {
+	public MavenBuildAssert hasDescription(String description) {
 		return hasText("/project/description", description);
 	}
 
@@ -126,85 +123,39 @@ public class PomAssert {
 	 * Assert {@code pom.xml} defines the specified property.
 	 * @param name the name of the property
 	 * @param value the value of the property
-	 * @return this
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert hasProperty(String name, String value) {
+	public MavenBuildAssert hasProperty(String name, String value) {
 		return hasText("/project/properties/" + name, value);
 	}
 
 	/**
-	 * Assert {@code pom.xml} does not defined the specified property.
+	 * Assert {@code pom.xml} does not define the specified property.
 	 * @param name the name of the property
-	 * @return this
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert doesNotHaveProperty(String name) {
+	public MavenBuildAssert doesNotHaveProperty(String name) {
 		return doesNotHaveNode("/project/properties/" + name);
 	}
 
-	/**
-	 * Assert {@code pom.xml} defines the specified Java version.
-	 * @param javaVersion the java version of the project
-	 * @return this
-	 */
-	public PomAssert hasJavaVersion(String javaVersion) {
-		return hasProperty("java.version", javaVersion);
-	}
-
 	/**
 	 * Assert {@code pom.xml} defines the specified number of dependencies.
-	 * @param count the number of dependencies
-	 * @return this
+	 * @param size the number of dependencies
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert hasDependenciesCount(int count) {
-		assertThat(this.pom).nodesAtPath("project/dependencies/dependency").hasSize(count);
+	public MavenBuildAssert hasDependenciesSize(int size) {
+		this.pom.nodesAtPath("project/dependencies/dependency").hasSize(size);
 		return this;
 	}
 
-	/**
-	 * Assert {@code pom.xml} defines the specified starter.
-	 * @param starterId the id of the starter (e.g. {@code web} for
-	 * {@code spring-boot-starter-web}.
-	 * @return this
-	 */
-	public PomAssert hasSpringBootStarterDependency(String starterId) {
-		return hasDependency("org.springframework.boot", "spring-boot-starter-" + starterId);
-	}
-
-	/**
-	 * Assert {@code pom.xml} defines the specified starter in the specified scope.
-	 * @param starterId the id of the starter (e.g. {@code web} for
-	 * {@code spring-boot-starter-web}.
-	 * @param scope the scope of the starter
-	 * @return this
-	 */
-	public PomAssert hasSpringBootStarterDependency(String starterId, String scope) {
-		return hasDependency("org.springframework.boot", "spring-boot-starter-" + starterId, null, scope);
-	}
-
-	/**
-	 * Assert {@code pom.xml} defines the root {@code spring-boot-starter} starter.
-	 * @return this
-	 */
-	public PomAssert hasSpringBootStarterRootDependency() {
-		return hasDependency("org.springframework.boot", "spring-boot-starter");
-	}
-
-	/**
-	 * Assert {@code pom.xml} defines the {@code spring-boot-starter-test} starter.
-	 * @return this
-	 */
-	public PomAssert hasSpringBootStarterTest() {
-		return hasSpringBootStarterDependency("test", "test");
-	}
-
 	/**
 	 * Assert {@code pom.xml} defines the specified dependency with no version and compile
 	 * scope.
 	 * @param groupId the groupId of the dependency
 	 * @param artifactId the artifactId of the dependency
-	 * @return this
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert hasDependency(String groupId, String artifactId) {
+	public MavenBuildAssert hasDependency(String groupId, String artifactId) {
 		return hasDependency(groupId, artifactId, null);
 	}
 
@@ -213,9 +164,9 @@ public class PomAssert {
 	 * @param groupId the groupId of the dependency
 	 * @param artifactId the artifactId of the dependency
 	 * @param version the version of the dependency
-	 * @return this
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert hasDependency(String groupId, String artifactId, String version) {
+	public MavenBuildAssert hasDependency(String groupId, String artifactId, String version) {
 		return hasDependency(Dependency.create(groupId, artifactId, version, "compile"));
 	}
 
@@ -225,36 +176,35 @@ public class PomAssert {
 	 * @param artifactId the artifactId of the dependency
 	 * @param version the version of the dependency
 	 * @param scope the scope of the dependency
-	 * @return this
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert hasDependency(String groupId, String artifactId, String version, String scope) {
+	public MavenBuildAssert hasDependency(String groupId, String artifactId, String version, String scope) {
 		return hasDependency(Dependency.create(groupId, artifactId, version, scope));
 	}
 
 	/**
 	 * Assert {@code pom.xml} defines the specified dependency.
 	 * @param dependency the dependency
-	 * @return this
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert hasDependency(Dependency dependency) {
-		assertThat(this.pom).nodesAtPath("/project/dependencies/dependency").areExactly(1,
-				new Condition<>((candidate) -> {
-					Dependency actual = toDependency(candidate);
-					if (dependency.getGroupId().equals(actual.getGroupId())
-							&& dependency.getArtifactId().equals(actual.getArtifactId())) {
-						if (dependency.getVersion() != null) {
-							assertThat(actual.getVersion()).isEqualTo(dependency.getVersion());
-						}
-						if (dependency.getScope() != null) {
-							assertThat(actual.getScope()).isEqualTo(dependency.getScope());
-						}
-						if (dependency.getType() != null) {
-							assertThat(actual.getType()).isEqualTo(dependency.getType());
-						}
-						return true;
-					}
-					return false;
-				}, "matching dependency"));
+	public MavenBuildAssert hasDependency(Dependency dependency) {
+		this.pom.nodesAtPath("/project/dependencies/dependency").areExactly(1, new Condition<>((candidate) -> {
+			Dependency actual = toDependency(candidate);
+			if (dependency.getGroupId().equals(actual.getGroupId())
+					&& dependency.getArtifactId().equals(actual.getArtifactId())) {
+				if (dependency.getVersion() != null) {
+					new StringAssert(actual.getVersion()).isEqualTo(dependency.getVersion());
+				}
+				if (dependency.getScope() != null) {
+					new StringAssert(actual.getScope()).isEqualTo(dependency.getScope());
+				}
+				if (dependency.getType() != null) {
+					new StringAssert(actual.getType()).isEqualTo(dependency.getType());
+				}
+				return true;
+			}
+			return false;
+		}, "matching dependency"));
 		return this;
 	}
 
@@ -263,10 +213,10 @@ public class PomAssert {
 	 * {@code groupId} and {@code artifactId}.
 	 * @param groupId the dependency's groupId
 	 * @param artifactId the dependency's artifactId
-	 * @return this
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert doesNotHaveDependency(String groupId, String artifactId) {
-		assertThat(this.pom).nodesAtPath("/project/dependencies/dependency").noneMatch((candidate) -> {
+	public MavenBuildAssert doesNotHaveDependency(String groupId, String artifactId) {
+		this.pom.nodesAtPath("/project/dependencies/dependency").noneMatch((candidate) -> {
 			Dependency actual = toDependency(candidate);
 			return groupId.equals(actual.getGroupId()) && artifactId.equals(actual.getArtifactId());
 		});
@@ -275,11 +225,11 @@ public class PomAssert {
 
 	/**
 	 * Assert {@code pom.xml} defines the specified number of boms.
-	 * @param count the number of boms
-	 * @return this
+	 * @param size the number of boms
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert hasBomsCount(int count) {
-		assertThat(this.pom).nodesAtPath("/project/dependencyManagement/dependencies/dependency").hasSize(count);
+	public MavenBuildAssert hasBomsSize(int size) {
+		this.pom.nodesAtPath("/project/dependencyManagement/dependencies/dependency").hasSize(size);
 		return this;
 	}
 
@@ -288,10 +238,10 @@ public class PomAssert {
 	 * @param groupId the groupId of the bom
 	 * @param artifactId the artifactId of the bom
 	 * @param version the version of the bom
-	 * @return this
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert hasBom(String groupId, String artifactId, String version) {
-		assertThat(this.pom).nodesAtPath("/project/dependencyManagement/dependencies/dependency").areExactly(1,
+	public MavenBuildAssert hasBom(String groupId, String artifactId, String version) {
+		this.pom.nodesAtPath("/project/dependencyManagement/dependencies/dependency").areExactly(1,
 				new Condition<>((candidate) -> {
 					BillOfMaterials actual = toBom(candidate);
 					return (actual != null && actual.getGroupId().equals(groupId)
@@ -302,11 +252,11 @@ public class PomAssert {
 
 	/**
 	 * Assert {@code pom.xml} defines the specified number of repositories.
-	 * @param count the number of repositories
-	 * @return this
+	 * @param size the number of repositories
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert hasRepositoriesCount(int count) {
-		assertThat(this.pom).nodesAtPath("/project/repositories/repository").hasSize(count);
+	public MavenBuildAssert hasRepositoriesSize(int size) {
+		this.pom.nodesAtPath("/project/repositories/repository").hasSize(size);
 		return this;
 	}
 
@@ -316,32 +266,31 @@ public class PomAssert {
 	 * @param name the name of the repository
 	 * @param url the url of the repository
 	 * @param snapshotsEnabled whether snapshot is enabled for the repository
-	 * @return this
+	 * @return {@code this} assertion object
 	 */
-	public PomAssert hasRepository(String id, String name, String url, Boolean snapshotsEnabled) {
-		assertThat(this.pom).nodesAtPath("/project/repositories/repository").areExactly(1,
-				new Condition<>((candidate) -> {
-					String actualId = ((Element) candidate).getElementsByTagName("id").item(0).getTextContent();
-					if (actualId.equals(id)) {
-						Repository repository = toRepository(candidate);
-						if (name != null) {
-							assertThat(repository.getName()).isEqualTo(name);
-						}
-						if (url != null) {
-							try {
-								assertThat(repository.getUrl()).isEqualTo(new URL(url));
-							}
-							catch (MalformedURLException ex) {
-								throw new IllegalArgumentException("Cannot parse URL", ex);
-							}
-						}
-						if (snapshotsEnabled) {
-							assertThat(repository.isSnapshotsEnabled()).isEqualTo(snapshotsEnabled);
-						}
-						return true;
+	public MavenBuildAssert hasRepository(String id, String name, String url, Boolean snapshotsEnabled) {
+		this.pom.nodesAtPath("/project/repositories/repository").areExactly(1, new Condition<>((candidate) -> {
+			String actualId = ((Element) candidate).getElementsByTagName("id").item(0).getTextContent();
+			if (actualId.equals(id)) {
+				Repository repository = toRepository(candidate);
+				if (name != null) {
+					new StringAssert(repository.getName()).isEqualTo(name);
+				}
+				if (url != null) {
+					try {
+						new UrlAssert(repository.getUrl()).isEqualTo(new URL(url));
 					}
-					return false;
-				}, "matching repository"));
+					catch (MalformedURLException ex) {
+						throw new IllegalArgumentException("Cannot parse URL", ex);
+					}
+				}
+				if (snapshotsEnabled) {
+					new BooleanAssert(repository.isSnapshotsEnabled()).isEqualTo(snapshotsEnabled);
+				}
+				return true;
+			}
+			return false;
+		}, "matching repository"));
 		return this;
 	}
 
@@ -350,28 +299,8 @@ public class PomAssert {
 	 * @param path the path of the node
 	 * @return this
 	 */
-	public PomAssert doesNotHaveNode(String path) {
-		assertThat(this.pom.nodeAtPath(path)).isNull();
-		return this;
-	}
-
-	/**
-	 * Assert {@code pom.xml} contains the specified expression.
-	 * @param expression an expected expression
-	 * @return this
-	 */
-	public PomAssert contains(String expression) {
-		assertThat(this.content).contains(expression);
-		return this;
-	}
-
-	/**
-	 * Assert {@code pom.xml} does not contain the specified expression.
-	 * @param expression an unexpected expression
-	 * @return this
-	 */
-	public PomAssert doesNotContain(String expression) {
-		assertThat(this.content).doesNotContain(expression);
+	public MavenBuildAssert doesNotHaveNode(String path) {
+		this.pom.nodeAtPath(path).isNull();
 		return this;
 	}
 
@@ -381,8 +310,8 @@ public class PomAssert {
 	 * @param value the expected value of the element
 	 * @return this
 	 */
-	public PomAssert hasText(String path, String value) {
-		assertThat(this.pom).textAtPath(path).isEqualTo(value);
+	public MavenBuildAssert hasText(String path, String value) {
+		this.pom.textAtPath(path).isEqualTo(value);
 		return this;
 	}
 

initializr-generator-test/src/main/java/io/spring/initializr/generator/test/io/AbstractTextAssert.java

@@ -0,0 +1,87 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.generator.test.io;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Path;
+
+import org.assertj.core.api.AbstractStringAssert;
+import org.assertj.core.api.ListAssert;
+
+import org.springframework.core.io.Resource;
+import org.springframework.util.StreamUtils;
+
+/**
+ * Base class for text assertions.
+ *
+ * @param <SELF> the type of the concrete assert implementations
+ * @author Stephane Nicoll
+ */
+public abstract class AbstractTextAssert<SELF extends AbstractStringAssert<SELF>> extends AbstractStringAssert<SELF> {
+
+	protected AbstractTextAssert(String actual, Class<?> selfType) {
+		super(actual, selfType);
+	}
+
+	protected AbstractTextAssert(Path textFile, Class<?> selfType) {
+		this(TextTestUtils.readContent(textFile), selfType);
+		this.info.description("Content at " + textFile);
+	}
+
+	/**
+	 * Assert this text has the same content as the content defined by the specified
+	 * {@link Resource}. Differences in newlines are ignored
+	 * @param expected a resource with the expected content
+	 * @return {@code this} assertion object
+	 * @see #isEqualToIgnoringNewLines(CharSequence)
+	 */
+	public SELF hasSameContentAs(Resource expected) {
+		if (!expected.isReadable()) {
+			failWithMessage("Expected resource does not exist: " + expected);
+		}
+		try (InputStream in = expected.getInputStream()) {
+			String expectedContent = StreamUtils.copyToString(in, StandardCharsets.UTF_8);
+			isEqualToIgnoringNewLines(expectedContent);
+		}
+		catch (IOException ex) {
+			failWithMessage("Cannot read expected content " + expected);
+		}
+		return this.myself;
+	}
+
+	/**
+	 * Assert this text contains exactly the specified lines.
+	 * @param lines the lines that constitute the content of this text
+	 * @return {@code this} assertion object
+	 */
+	public SELF containsExactly(String... lines) {
+		lines().containsExactly(lines);
+		return this.myself;
+	}
+
+	/**
+	 * Return an {@link ListAssert assert} for the lines that constitute this text, to
+	 * allow chaining of lines-specific assertions from this call.
+	 * @return a {@link ListAssert} for the lines that constitutes this text
+	 */
+	public ListAssert<String> lines() {
+		return new ListAssert<>(TextTestUtils.readAllLines(this.actual));
+	}
+
+}

initializr-generator-test/src/main/java/io/spring/initializr/generator/test/io/TextAssert.java

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.generator.test.io;
+
+import java.nio.file.Path;
+
+/**
+ * Assertions for text content.
+ *
+ * @author Stephane Nicoll
+ */
+public class TextAssert extends AbstractTextAssert<TextAssert> {
+
+	public TextAssert(String actual) {
+		super(actual, TextAssert.class);
+	}
+
+	public TextAssert(Path textFile) {
+		super(textFile, TextAssert.class);
+	}
+
+}

initializr-generator-test/src/main/java/io/spring/initializr/generator/test/io/TextTestUtils.java

@@ -43,18 +43,6 @@ public final class TextTestUtils {
 		return Arrays.asList(lines);
 	}
 
-	/**
-	 * Read all lines from the specified {@link Path source}. Check the given
-	 * {@code source} is a regular file that ends with a new line.
-	 * @param source a text file
-	 * @return all lines from the file
-	 */
-	public static List<String> readAllLines(Path source) {
-		String content = readContent(source);
-		assertThat(content).endsWith(System.lineSeparator());
-		return readAllLines(content);
-	}
-
 	/**
 	 * Read the content from the specified {@link Path source}. Check the given
 	 * {@code source} is a regular file.

initializr-generator-test/src/main/java/io/spring/initializr/generator/test/language/SourceCodeAssert.java

@@ -1,80 +0,0 @@
-/*
- * Copyright 2012-2019 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package io.spring.initializr.generator.test.language;
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.nio.charset.StandardCharsets;
-
-import org.springframework.core.io.Resource;
-import org.springframework.util.StreamUtils;
-
-import static org.assertj.core.api.Assertions.assertThat;
-
-/**
- * Source code assertions.
- *
- * @author Stephane Nicoll
- */
-public class SourceCodeAssert {
-
-	private final String name;
-
-	private final String content;
-
-	public SourceCodeAssert(String name, String content) {
-		this.name = name;
-		this.content = content.replaceAll("\r\n", "\n");
-	}
-
-	public SourceCodeAssert equalsTo(Resource expected) {
-		try (InputStream in = expected.getInputStream()) {
-			String expectedContent = StreamUtils.copyToString(in, StandardCharsets.UTF_8);
-			assertThat(this.content).describedAs("Content for %s", this.name)
-					.isEqualTo(expectedContent.replaceAll("\r\n", "\n"));
-		}
-		catch (IOException ex) {
-			throw new IllegalStateException("Cannot read file", ex);
-		}
-		return this;
-	}
-
-	public SourceCodeAssert hasImports(String... classNames) {
-		for (String className : classNames) {
-			contains("import " + className);
-		}
-		return this;
-	}
-
-	public SourceCodeAssert doesNotHaveImports(String... classNames) {
-		for (String className : classNames) {
-			doesNotContain("import " + className);
-		}
-		return this;
-	}
-
-	public SourceCodeAssert contains(String... expressions) {
-		assertThat(this.content).describedAs("Content for %s", this.name).contains(expressions);
-		return this;
-	}
-
-	public SourceCodeAssert doesNotContain(String... expressions) {
-		assertThat(this.content).describedAs("Content for %s", this.name).doesNotContain(expressions);
-		return this;
-	}
-
-}

initializr-generator-test/src/main/java/io/spring/initializr/generator/test/project/AbstractJvmModuleAssert.java

@@ -0,0 +1,158 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.generator.test.project;
+
+import java.nio.file.Path;
+
+import io.spring.initializr.generator.language.Language;
+import io.spring.initializr.generator.language.SourceStructure;
+import io.spring.initializr.generator.test.io.TextAssert;
+import org.assertj.core.api.PathAssert;
+
+import org.springframework.util.StringUtils;
+
+/**
+ * Base class for JVM module assertions.
+ *
+ * @param <SELF> the type of the concrete assert implementations
+ * @author Stephane Nicoll
+ */
+public abstract class AbstractJvmModuleAssert<SELF extends AbstractJvmModuleAssert<SELF>>
+		extends AbstractProjectAssert<SELF> {
+
+	private final SourceStructure mainDirectory;
+
+	private final SourceStructure testDirectory;
+
+	private final String sourceFileExtension;
+
+	protected AbstractJvmModuleAssert(Path projectDirectory, Language language, String sourceFileExtension,
+			Class<?> selfType) {
+		super(projectDirectory, selfType);
+		this.mainDirectory = new SourceStructure(projectDirectory.resolve("src/main/"), language.id());
+		this.testDirectory = new SourceStructure(projectDirectory.resolve("src/test/"), language.id());
+		this.sourceFileExtension = sourceFileExtension;
+	}
+
+	/**
+	 * Assert that the main source defines the specified package.
+	 * @param packageName the name of the package
+	 * @return {@code this} assertion object
+	 */
+	public SELF hasMainPackage(String packageName) {
+		return hasPackage(this.mainDirectory.getSourcesDirectory(), packageName);
+	}
+
+	/**
+	 * Assert that the main source defines the specified type.
+	 * @param packageName the name of a package
+	 * @param name the name of the type
+	 * @return {@code this} assertion object
+	 */
+	public SELF hasMainSource(String packageName, String name) {
+		validateAndGetAsset(this.mainDirectory.getSourcesDirectory(), packageName, name);
+		return this.myself;
+	}
+
+	/**
+	 * Assert that the main source defines the specified type and return an
+	 * {@link TextAssert assert} for it, to allow chaining of text-specific assertions
+	 * from this call.
+	 * @param packageName the name of a package
+	 * @param name the name of the type
+	 * @return a {@link TextAssert} for the specified source
+	 */
+	public TextAssert mainSource(String packageName, String name) {
+		return new TextAssert(validateAndGetAsset(this.mainDirectory.getSourcesDirectory(), packageName, name));
+	}
+
+	/**
+	 * Assert that the main resources defines the specified resource.
+	 * @param resourcePath the path of a resource relative to the {@code resources}
+	 * directory
+	 * @return {@code this} assertion object
+	 */
+	public SELF hasMainResource(String resourcePath) {
+		return hasResource(this.mainDirectory.getRootDirectory().resolve("resources"), resourcePath);
+	}
+
+	/**
+	 * Assert that the test source defines the specified package.
+	 * @param packageName the name of the package
+	 * @return {@code this} assertion object
+	 */
+	public SELF hasTestPackage(String packageName) {
+		return hasPackage(this.testDirectory.getSourcesDirectory(), packageName);
+	}
+
+	/**
+	 * Assert that the test source defines the specified type.
+	 * @param packageName the name of a package
+	 * @param name the name of the type
+	 * @return {@code this} assertion object
+	 */
+	public SELF hasTestSource(String packageName, String name) {
+		validateAndGetAsset(this.testDirectory.getSourcesDirectory(), packageName, name);
+		return this.myself;
+	}
+
+	/**
+	 * Assert that the test source defines the specified type and return an
+	 * {@link TextAssert assert} for it, to allow chaining of text-specific assertions
+	 * from this call.
+	 * @param packageName the name of a package
+	 * @param name the name of the type
+	 * @return a {@link TextAssert} for the specified source
+	 */
+	public TextAssert testSource(String packageName, String name) {
+		return new TextAssert(validateAndGetAsset(this.testDirectory.getSourcesDirectory(), packageName, name));
+	}
+
+	private SELF hasPackage(Path baseDir, String packageName) {
+		Path expected = baseDir.resolve(packageToPath(packageName));
+		new PathAssert(expected).exists().isDirectory();
+		return this.myself;
+	}
+
+	private Path validateAndGetAsset(Path baseDir, String packageName, String name) {
+		Path source = resolveSource(baseDir, packageName, name);
+		new PathAssert(source)
+				.as("Source '%s.%s' not found in package '%s'", name, this.sourceFileExtension, packageName).exists()
+				.isRegularFile();
+		return source;
+	}
+
+	private SELF hasResource(Path baseDir, String relativePath) {
+		Path path = baseDir.resolve(relativePath);
+		new PathAssert(path).as("Resource '%s' not found", relativePath).exists().isRegularFile();
+		return this.myself;
+	}
+
+	private Path resolveSource(Path baseDir, String packageName, String name) {
+		return baseDir.resolve(createSourceRelativePath(packageName, name));
+	}
+
+	private String createSourceRelativePath(String packageName, String name) {
+		return packageToPath(packageName) + "/" + name + "." + this.sourceFileExtension;
+	}
+
+	private static String packageToPath(String packageName) {
+		String packagePath = packageName.replace(".", "/");
+		return StringUtils.trimTrailingCharacter(packagePath, '/');
+	}
+
+}

initializr-generator-test/src/main/java/io/spring/initializr/generator/test/project/AbstractModuleAssert.java

@@ -0,0 +1,112 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.generator.test.project;
+
+import java.nio.file.Path;
+
+import io.spring.initializr.generator.language.Language;
+import io.spring.initializr.generator.test.buildsystem.gradle.GroovyDslGradleBuildAssert;
+import io.spring.initializr.generator.test.buildsystem.maven.MavenBuildAssert;
+
+/**
+ * Base class for module assertions.
+ *
+ * @param <SELF> the type of the concrete assert implementations
+ * @author Stephane Nicoll
+ */
+public abstract class AbstractModuleAssert<SELF extends AbstractModuleAssert<SELF>>
+		extends AbstractProjectAssert<SELF> {
+
+	protected AbstractModuleAssert(Path projectDirectory, Class<?> selfType) {
+		super(projectDirectory, selfType);
+	}
+
+	/**
+	 * Return a {@link JvmModuleAssert JVM module} assertion for the specified
+	 * {@link Language} and file source extension, to allow chaining of jvm
+	 * module-specific assertions from this call.
+	 * <p>
+	 * Does not validate that the module has source code for the specified language.
+	 * @param language the language of the module
+	 * @param sourceFileExtension the source file extension
+	 * @return a {@link JvmModuleAssert} for the specified language
+	 */
+	public JvmModuleAssert asJvmModule(Language language, String sourceFileExtension) {
+		return new JvmModuleAssert(this.actual, language, sourceFileExtension);
+	}
+
+	/**
+	 * Assert the module defines a {@code pom.xml}.
+	 * @return {@code this} assertion object
+	 */
+	public SELF hasMavenBuild() {
+		filePaths().contains("pom.xml");
+		return this.myself;
+	}
+
+	/**
+	 * Assert the module defines the Maven wrapper.
+	 * @return {@code this} assertion object
+	 */
+	public SELF hasMavenWrapper() {
+		filePaths().contains("mvnw", "mvnw.cmd", ".mvn/wrapper/maven-wrapper.properties",
+				".mvn/wrapper/maven-wrapper.jar");
+		return this.myself;
+	}
+
+	/**
+	 * Assert this module has a {@code pom.xml} and return an {@link MavenBuildAssert
+	 * assert} for the {@code pom.xml} file of this module, to allow chaining of
+	 * maven-specific assertions from this call.
+	 * @return a {@link MavenBuildAssert}
+	 */
+	public MavenBuildAssert mavenBuild() {
+		hasMavenBuild();
+		return new MavenBuildAssert(this.actual.resolve("pom.xml"));
+	}
+
+	/**
+	 * Assert the module defines a {@code build.gradle}.
+	 * @return {@code this} assertion object
+	 */
+	public SELF hasGroovyDslGradleBuild() {
+		filePaths().contains("build.gradle");
+		return this.myself;
+	}
+
+	/**
+	 * Assert the module defines the Gradle wrapper.
+	 * @return {@code this} assertion object
+	 */
+	public SELF hasGradleWrapper() {
+		filePaths().contains("gradlew", "gradlew.bat", "gradle/wrapper/gradle-wrapper.properties",
+				"gradle/wrapper/gradle-wrapper.jar");
+		return this.myself;
+	}
+
+	/**
+	 * Assert this module has a {@code build.gradle} and return an
+	 * {@link GroovyDslGradleBuildAssert assert} for the {@code build.gradle} file of this
+	 * module, to allow chaining of gradle-specific assertions from this call.
+	 * @return a {@link GroovyDslGradleBuildAssert}
+	 */
+	public GroovyDslGradleBuildAssert groovyDslGradleBuild() {
+		hasGroovyDslGradleBuild();
+		return new GroovyDslGradleBuildAssert(this.actual.resolve("build.gradle"));
+	}
+
+}

initializr-generator-test/src/main/java/io/spring/initializr/generator/test/project/AbstractProjectAssert.java

@@ -0,0 +1,157 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.generator.test.project;
+
+import java.io.IOException;
+import java.nio.file.FileSystems;
+import java.nio.file.FileVisitResult;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.SimpleFileVisitor;
+import java.nio.file.attribute.BasicFileAttributes;
+import java.util.ArrayList;
+import java.util.List;
+
+import io.spring.initializr.generator.test.io.TextAssert;
+import org.assertj.core.api.AbstractPathAssert;
+import org.assertj.core.api.ListAssert;
+import org.assertj.core.api.PathAssert;
+
+/**
+ * Base class for project assertions.
+ *
+ * @param <SELF> the type of the concrete assert implementations
+ * @author Stephane Nicoll
+ */
+public abstract class AbstractProjectAssert<SELF extends AbstractProjectAssert<SELF>> extends AbstractPathAssert<SELF> {
+
+	private ListAssert<String> filesAssert;
+
+	protected AbstractProjectAssert(Path projcetDirectory, Class<?> selfType) {
+		super(projcetDirectory, selfType);
+	}
+
+	/**
+	 * Assert the project has the specified directories.
+	 * @param directoryPaths the directories relative to the project directory.
+	 * @return {@code this} assertion object
+	 */
+	public SELF containsDirectories(String... directoryPaths) {
+		for (String directory : directoryPaths) {
+			new PathAssert(this.actual.resolve(directory)).exists().isDirectory();
+		}
+		return this.myself;
+	}
+
+	/**
+	 * Assert the project does not have the specified directories.
+	 * @param directoryPaths the directory paths relative to the project directory.
+	 * @return {@code this} assertion object
+	 */
+	public SELF doesNotContainDirectories(String... directoryPaths) {
+		for (String directory : directoryPaths) {
+			new PathAssert(this.actual.resolve(directory)).doesNotExist();
+		}
+		return this.myself;
+	}
+
+	/**
+	 * Assert the project has the specified files.
+	 * @param filePaths the file paths relative to the project directory.
+	 * @return {@code this} assertion object
+	 */
+	public SELF containsFiles(String... filePaths) {
+		filePaths().contains(filePaths);
+		return this.myself;
+	}
+
+	/**
+	 * Assert the project does not have the specified files.
+	 * @param filePaths the file paths relative to the project directory.
+	 * @return {@code this} assertion object
+	 */
+	public SELF doesNotContainFiles(String... filePaths) {
+		filePaths().doesNotContain(filePaths);
+		return this.myself;
+	}
+
+	/**
+	 * Return an {@link ListAssert assert} for the local file paths of this project, to
+	 * allow chaining of list-specific assertions from this call.
+	 * @return a {@link ListAssert} with the files of this project
+	 */
+	public ListAssert<String> filePaths() {
+		if (this.filesAssert == null) {
+			this.filesAssert = new ListAssert<>(getRelativePathsOfProjectFiles());
+		}
+		return this.filesAssert;
+	}
+
+	/**
+	 * Assert that the project defines the specified file and return a {@link PathAssert}
+	 * for it, to allow chaining of Path-specific assertions from this call.
+	 * @param path the path of the file
+	 * @return a {@link PathAssert} for the specified file
+	 */
+	public PathAssert file(String path) {
+		Path file = this.actual.resolve(path);
+		return new PathAssert(file).exists().isRegularFile();
+	}
+
+	/**
+	 * Assert that the project defines the specified file and return a {@link TextAssert}
+	 * for it, to allow chaining of text file-specific assertions from this call.
+	 * @param path the path of a text file
+	 * @return a {@link TextAssert} for the specified text file
+	 */
+	public TextAssert textFile(String path) {
+		Path file = this.actual.resolve(path);
+		new PathAssert(file).exists().isRegularFile();
+		return new TextAssert(file);
+	}
+
+	/**
+	 * Return the relative paths of all files. For consistency, always use {@code /} as
+	 * path separator.
+	 * @return the relative path of all files
+	 */
+	private List<String> getRelativePathsOfProjectFiles() {
+		List<String> relativePaths = new ArrayList<>();
+		try {
+			Files.walkFileTree(this.actual, new SimpleFileVisitor<Path>() {
+				@Override
+				public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) {
+					relativePaths.add(createRelativePath(file));
+					return FileVisitResult.CONTINUE;
+				}
+			});
+		}
+		catch (IOException ex) {
+			throw new IllegalStateException(ex);
+		}
+		return relativePaths;
+	}
+
+	private String createRelativePath(Path file) {
+		String relativePath = this.actual.relativize(file).toString();
+		if (FileSystems.getDefault().getSeparator().equals("\\")) {
+			return relativePath.replace('\\', '/');
+		}
+		return relativePath;
+	}
+
+}

initializr-generator-test/src/main/java/io/spring/initializr/generator/test/project/JvmModuleAssert.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.generator.test.project;
+
+import java.nio.file.Path;
+
+import io.spring.initializr.generator.language.Language;
+
+/**
+ * Assertions for a module with code for a particular {@link Language}.
+ *
+ * @author Stephane Nicoll
+ */
+public class JvmModuleAssert extends AbstractJvmModuleAssert<JvmModuleAssert> {
+
+	public JvmModuleAssert(Path projectDirectory, Language language, String sourceFileExtension) {
+		super(projectDirectory, language, sourceFileExtension, JvmModuleAssert.class);
+	}
+
+}

initializr-generator-test/src/main/java/io/spring/initializr/generator/test/project/ModuleAssert.java

@@ -14,7 +14,19 @@
  * limitations under the License.
  */
 
+package io.spring.initializr.generator.test.project;
+
+import java.nio.file.Path;
+
 /**
- * Support for testing source code.
+ * Assertions for a module.
+ *
+ * @author Stephane Nicoll
  */
-package io.spring.initializr.generator.test.language;
+public class ModuleAssert extends AbstractModuleAssert<ModuleAssert> {
+
+	public ModuleAssert(Path projectDirectory) {
+		super(projectDirectory, ModuleAssert.class);
+	}
+
+}

initializr-generator-test/src/main/java/io/spring/initializr/generator/test/project/ProjectAssert.java

@@ -1,248 +0,0 @@
-/*
- * Copyright 2012-2019 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package io.spring.initializr.generator.test.project;
-
-import java.io.File;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.util.Properties;
-
-import io.spring.initializr.generator.test.buildsystem.gradle.GradleBuildAssert;
-import io.spring.initializr.generator.test.buildsystem.gradle.GradleSettingsAssert;
-import io.spring.initializr.generator.test.buildsystem.maven.PomAssert;
-import io.spring.initializr.generator.test.io.TextTestUtils;
-import io.spring.initializr.generator.test.language.SourceCodeAssert;
-
-import org.springframework.core.io.FileSystemResource;
-import org.springframework.core.io.support.PropertiesLoaderUtils;
-import org.springframework.util.StringUtils;
-
-import static org.assertj.core.api.Assertions.assertThat;
-
-/**
- * Various project based assertions.
- *
- * @author Stephane Nicoll
- */
-public class ProjectAssert {
-
-	/**
-	 * Default package name.
-	 */
-	public static final String DEFAULT_PACKAGE_NAME = "com.example.demo";
-
-	/**
-	 * Default application name.
-	 */
-	public static final String DEFAULT_APPLICATION_NAME = "DemoApplication";
-
-	private final ProjectStructure projectStructure;
-
-	/**
-	 * Create a new instance with the directory holding the generated project.
-	 * @param dir the directory of the project
-	 */
-	public ProjectAssert(Path dir) {
-		this.projectStructure = new ProjectStructure(dir);
-	}
-
-	public ProjectStructure getProjectStructure() {
-		return this.projectStructure;
-	}
-
-	/**
-	 * Validate that the project contains a base directory with the specified name.
-	 * <p>
-	 * When extracting such archive, a directory with the specified {@code name} will be
-	 * created with the content of the project instead of extracting it in the directory
-	 * itself.
-	 * @param name the expected name of the base directory
-	 * @return an updated project assert on that base directory
-	 */
-	public ProjectAssert hasBaseDir(String name) {
-		Path projectDir = this.projectStructure.resolve(name);
-		assertThat(projectDir)
-				.describedAs("No directory %s found in %s", name, this.projectStructure.getProjectDirectory()).exists();
-		assertThat(projectDir).isDirectory();
-		// Replacing the root dir so that other assertions match the root
-		return new ProjectAssert(projectDir);
-	}
-
-	/**
-	 * Return a {@link PomAssert} for this project.
-	 * @return a POM assert
-	 */
-	public PomAssert pomAssert() {
-		return new PomAssert(TextTestUtils.readContent(this.projectStructure.resolve("pom.xml")));
-	}
-
-	/**
-	 * Return a {@link GradleBuildAssert} for this project.
-	 * @return a gradle assert
-	 */
-	public GradleBuildAssert gradleBuildAssert() {
-		return new GradleBuildAssert(TextTestUtils.readContent(this.projectStructure.resolve("build.gradle")));
-	}
-
-	/**
-	 * Return a {@link GradleSettingsAssert} for this project.
-	 * @return a Gradle Settings assertion utility
-	 */
-	public GradleSettingsAssert gradleSettingsAssert() {
-		return new GradleSettingsAssert(TextTestUtils.readContent(this.projectStructure.resolve("settings.gradle")));
-	}
-
-	/**
-	 * Return a {@link SourceCodeAssert} for the specified source code.
-	 * @param sourceCodePath the source code path
-	 * @return a source code assertion utility
-	 */
-	public SourceCodeAssert sourceCodeAssert(String sourceCodePath) {
-		hasFile(sourceCodePath);
-		return new SourceCodeAssert(sourceCodePath,
-				TextTestUtils.readContent(this.projectStructure.resolve(sourceCodePath)));
-	}
-
-	public ProjectAssert isMavenProject() {
-		hasFile("pom.xml").hasNoFile("build.gradle");
-		hasFile("mvnw", "mvnw.cmd", ".mvn/wrapper/maven-wrapper.properties", ".mvn/wrapper/maven-wrapper.jar");
-		return this;
-	}
-
-	public ProjectAssert isGradleProject(String version) {
-		hasFile("build.gradle").hasNoFile("pom.xml");
-		hasFile("gradlew", "gradlew.bat", "gradle/wrapper/gradle-wrapper.properties",
-				"gradle/wrapper/gradle-wrapper.jar");
-		if (StringUtils.hasText(version)) {
-			Properties properties = properties("gradle/wrapper/gradle-wrapper.properties");
-			String distributionUrl = properties.getProperty("distributionUrl");
-			assertThat(distributionUrl).contains(version);
-		}
-		return this;
-	}
-
-	public ProjectAssert isGradleProject() {
-		return isGradleProject(null);
-	}
-
-	public ProjectAssert isJavaProject(String expectedPackageName, String expectedApplicationName) {
-		return isGenericProject(expectedPackageName, expectedApplicationName, "java", "java");
-	}
-
-	public ProjectAssert isJavaProject() {
-		return isJavaProject(DEFAULT_PACKAGE_NAME, DEFAULT_APPLICATION_NAME);
-	}
-
-	public ProjectAssert isGroovyProject(String expectedPackageName, String expectedApplicationName) {
-		return isGenericProject(expectedPackageName, expectedApplicationName, "groovy", "groovy");
-	}
-
-	public ProjectAssert isKotlinProject(String expectedPackageName, String expectedApplicationName) {
-		return isGenericProject(expectedPackageName, expectedApplicationName, "kotlin", "kt");
-	}
-
-	public ProjectAssert isGroovyProject() {
-		return isGroovyProject(DEFAULT_PACKAGE_NAME, DEFAULT_APPLICATION_NAME);
-	}
-
-	public ProjectAssert isKotlinProject() {
-		return isKotlinProject(DEFAULT_PACKAGE_NAME, DEFAULT_APPLICATION_NAME);
-	}
-
-	public ProjectAssert isGenericProject(String expectedPackageName, String expectedApplicationName,
-			String codeLocation, String extension) {
-		String packageName = expectedPackageName.replace(".", "/");
-		return hasFile("src/main/" + codeLocation + "/" + packageName + "/" + expectedApplicationName + "." + extension,
-				"src/test/" + codeLocation + "/" + packageName + "/" + expectedApplicationName + "Tests." + extension,
-				"src/main/resources/application.properties");
-	}
-
-	public ProjectAssert isJavaWarProject(String expectedApplicationName) {
-		return isGenericWarProject(DEFAULT_PACKAGE_NAME, expectedApplicationName, "java", "java");
-	}
-
-	public ProjectAssert isJavaWarProject() {
-		return isJavaWarProject(DEFAULT_APPLICATION_NAME);
-	}
-
-	public ProjectAssert isGenericWarProject(String expectedPackageName, String expectedApplicationName,
-			String codeLocation, String extension) {
-		String packageName = expectedPackageName.replace(".", "/");
-		return isGenericProject(expectedPackageName, expectedApplicationName, codeLocation, extension)
-				.hasStaticAndTemplatesResources(true)
-				.hasFile("src/main/" + codeLocation + "/" + packageName + "/ServletInitializer." + extension);
-	}
-
-	public ProjectAssert hasStaticAndTemplatesResources(boolean web) {
-		assertFile("src/main/resources/templates", web);
-		return assertFile("src/main/resources/static", web);
-	}
-
-	public ProjectAssert hasFile(String... localPaths) {
-		assertThat(this.projectStructure.getRelativePathsOfProjectFiles()).contains(localPaths);
-		return this;
-	}
-
-	public ProjectAssert hasExecutableFile(String... localPaths) {
-		if (runningOnWindows()) {
-			for (String localPath : localPaths) {
-				assertFile(localPath, true);
-			}
-			return this;
-		}
-		for (String localPath : localPaths) {
-			assertExecutable(localPath, true);
-		}
-		return this;
-	}
-
-	public ProjectAssert hasNoFile(String... localPaths) {
-		assertThat(this.projectStructure.getRelativePathsOfProjectFiles()).doesNotContain(localPaths);
-		return this;
-	}
-
-	public ProjectAssert assertFile(String localPath, boolean exist) {
-		Path candidate = this.projectStructure.resolve(localPath);
-		assertThat(Files.exists(candidate)).describedAs("Invalid presence (%s) exist for %s", exist, localPath)
-				.isEqualTo(exist);
-		return this;
-	}
-
-	public ProjectAssert assertExecutable(String localPath, boolean exist) {
-		Path candidate = this.projectStructure.resolve(localPath);
-		assertThat(Files.exists(candidate)).describedAs("Invalid presence (%s) exist for %s", exist, localPath)
-				.isEqualTo(exist);
-		assertThat(Files.isExecutable(candidate)).describedAs("File (%s) is not an executable", localPath)
-				.isEqualTo(exist);
-		return this;
-	}
-
-	private boolean runningOnWindows() {
-		return File.separatorChar == '\\';
-	}
-
-	private Properties properties(String localPath) {
-		Path file = this.projectStructure.resolve(localPath);
-		try {
-			return PropertiesLoaderUtils.loadProperties(new FileSystemResource(file));
-		}
-		catch (Exception ex) {
-			throw new IllegalStateException("Cannot load Properties", ex);
-		}
-	}
-
-}

initializr-generator-test/src/main/java/io/spring/initializr/generator/test/project/ProjectStructure.java

@@ -16,24 +16,18 @@
 
 package io.spring.initializr.generator.test.project;
 
-import java.io.IOException;
-import java.nio.file.FileSystems;
-import java.nio.file.FileVisitResult;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.nio.file.SimpleFileVisitor;
-import java.nio.file.attribute.BasicFileAttributes;
-import java.util.ArrayList;
-import java.util.List;
 
-import io.spring.initializr.generator.test.io.TextTestUtils;
+import org.assertj.core.api.AssertProvider;
 
 /**
- * Test helper to assert content of a generated project structure.
+ * Represent a generated project structure and act as an entry point for AssertJ
+ * assertions.
  *
  * @author Stephane Nicoll
  */
-public class ProjectStructure {
+public final class ProjectStructure implements AssertProvider<ModuleAssert> {
 
 	private final Path projectDirectory;
 
@@ -45,6 +39,11 @@ public class ProjectStructure {
 		this.projectDirectory = projectDirectory;
 	}
 
+	@Override
+	public ModuleAssert assertThat() {
+		return new ModuleAssert(this.getProjectDirectory());
+	}
+
 	/**
 	 * Return the project directory.
 	 * @return the project directory
@@ -54,55 +53,17 @@ public class ProjectStructure {
 	}
 
 	/**
-	 * Resolve a {@link Path} relative to the project directory.
-	 * @param other the path string to resolve against the root of the project structure
-	 * @return the resulting path
-	 * @see Path#resolve(String)
+	 * Resolve a {@link ProjectStructure} based on the specified module name.
+	 * @param name the name of a sub-directory of the current project
+	 * @return a new {@link ProjectStructure} for the sub-directory
 	 */
-	public Path resolve(String other) {
-		return this.projectDirectory.resolve(other);
-	}
-
-	/**
-	 * Resolve a {@link Path} relative to the project directory and return all lines.
-	 * Check that the resolved {@link Path} is a regular text file that ends with a
-	 * newline.
-	 * @param other the path string to resolve against the root of the project structure
-	 * @return all lines from the resolve file
-	 * @see TextTestUtils#readAllLines(Path)
-	 */
-	public List<String> readAllLines(String other) {
-		return TextTestUtils.readAllLines(resolve(other));
-	}
-
-	/**
-	 * Return the relative paths of all files. For consistency, always use {@code /} as
-	 * path separator.
-	 * @return the relative path of all files
-	 */
-	public List<String> getRelativePathsOfProjectFiles() {
-		List<String> relativePaths = new ArrayList<>();
-		try {
-			Files.walkFileTree(this.projectDirectory, new SimpleFileVisitor<Path>() {
-				@Override
-				public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) {
-					relativePaths.add(createRelativePath(file));
-					return FileVisitResult.CONTINUE;
-				}
-			});
+	public ProjectStructure resolveModule(String name) {
+		Path projectDir = this.projectDirectory.resolve(name);
+		if (!Files.isDirectory(projectDir)) {
+			throw new IllegalArgumentException(
+					String.format("No directory '%s' found in '%s'", name, this.projectDirectory));
 		}
-		catch (IOException ex) {
-			throw new IllegalStateException(ex);
-		}
-		return relativePaths;
-	}
-
-	private String createRelativePath(Path file) {
-		String relativePath = this.projectDirectory.relativize(file).toString();
-		if (FileSystems.getDefault().getSeparator().equals("\\")) {
-			return relativePath.replace('\\', '/');
-		}
-		return relativePath;
+		return new ProjectStructure(projectDir);
 	}
 
 }

initializr-generator-test/src/test/java/io/spring/initializr/generator/test/buildsystem/gradle/GroovyDslGradleBuildAssertTests.java

@@ -0,0 +1,105 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.generator.test.buildsystem.gradle;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.charset.StandardCharsets;
+
+import org.assertj.core.api.AssertProvider;
+import org.junit.jupiter.api.Test;
+
+import org.springframework.core.io.ClassPathResource;
+import org.springframework.util.StreamUtils;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
+
+/**
+ * Tests for {@link GroovyDslGradleBuildAssert}.
+ *
+ * @author Stephane Nicoll
+ */
+class GroovyDslGradleBuildAssertTests {
+
+	@Test
+	void hasPluginWithId() {
+		assertThat(forSampleGradleBuild()).hasPlugin("java");
+	}
+
+	@Test
+	void hasPluginWithIdAndVersion() {
+		assertThat(forSampleGradleBuild()).hasPlugin("com.example", "1.0.0.RELEASE");
+	}
+
+	@Test
+	void hasPluginWrongId() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forSampleGradleBuild()).hasPlugin("com.another", "1.0.0.RELEASE"));
+	}
+
+	@Test
+	void hasPluginWrongValue() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forSampleGradleBuild()).hasPlugin("com.example", "2.0.0.RELEASE"));
+	}
+
+	@Test
+	void hasVersion() {
+		assertThat(forSampleGradleBuild()).hasVersion("0.0.1-SNAPSHOT");
+	}
+
+	@Test
+	void hasVersionWithWrongValue() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forSampleGradleBuild()).hasVersion("0.0.3-SNAPSHOT"));
+	}
+
+	@Test
+	void hasSourceCompatibility() {
+		assertThat(forSampleGradleBuild()).hasSourceCompatibility("1.8");
+	}
+
+	@Test
+	void hasSourceCompatibilityWithWrongValue() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forSampleGradleBuild()).hasSourceCompatibility("11"));
+	}
+
+	@Test
+	void containsOnlyExtProperties() {
+		assertThat(forSampleGradleBuild()).containsOnlyExtProperties("acmeVersion", "Brussels.SR2");
+	}
+
+	@Test
+	void containsOnlyExtPropertiesWithExtraValue() {
+		assertThatExceptionOfType(AssertionError.class).isThrownBy(() -> assertThat(forSampleGradleBuild())
+				.containsOnlyExtProperties("acmeVersion", "Brussels.SR2", "wrong", "1.0.0"));
+	}
+
+	private AssertProvider<GroovyDslGradleBuildAssert> forSampleGradleBuild() {
+		String path = "project/build/gradle/sample-build.gradle";
+		try (InputStream in = new ClassPathResource(path).getInputStream()) {
+			String content = StreamUtils.copyToString(in, StandardCharsets.UTF_8);
+			return () -> new GroovyDslGradleBuildAssert(content);
+		}
+		catch (IOException ex) {
+			throw new IllegalStateException("No content found at " + path, ex);
+		}
+	}
+
+}

initializr-generator-test/src/test/java/io/spring/initializr/generator/test/buildsystem/gradle/GroovyDslGradleSettingsAssertTests.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.generator.test.buildsystem.gradle;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.charset.StandardCharsets;
+
+import org.assertj.core.api.AssertProvider;
+import org.junit.jupiter.api.Test;
+
+import org.springframework.core.io.ClassPathResource;
+import org.springframework.util.StreamUtils;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
+
+/**
+ * Test for {@link GroovyDslGradleSettingsAssert}.
+ *
+ * @author Stephane Nicoll
+ */
+class GroovyDslGradleSettingsAssertTests {
+
+	@Test
+	void hasProjectName() {
+		assertThat(forSampleGradleSettings()).hasProjectName("demo");
+	}
+
+	@Test
+	void hasProjectNameWithWrongValue() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forSampleGradleSettings()).hasProjectName("another-project"));
+	}
+
+	private AssertProvider<GroovyDslGradleSettingsAssert> forSampleGradleSettings() {
+		String path = "project/build/gradle/sample-settings.gradle";
+		try (InputStream in = new ClassPathResource(path).getInputStream()) {
+			String content = StreamUtils.copyToString(in, StandardCharsets.UTF_8);
+			return () -> new GroovyDslGradleSettingsAssert(content);
+		}
+		catch (IOException ex) {
+			throw new IllegalStateException("No content found at " + path, ex);
+		}
+	}
+
+}

initializr-generator-test/src/test/java/io/spring/initializr/generator/test/buildsystem/maven/MavenBuildAssertTests.java

@@ -0,0 +1,307 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.generator.test.buildsystem.maven;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.charset.StandardCharsets;
+
+import org.assertj.core.api.AssertProvider;
+import org.junit.jupiter.api.Test;
+
+import org.springframework.core.io.ClassPathResource;
+import org.springframework.util.StreamUtils;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
+
+/**
+ * Tests for {@link MavenBuildAssert}.
+ *
+ * @author Stephane Nicoll
+ */
+class MavenBuildAssertTests {
+
+	@Test
+	void hasParent() {
+		assertThat(forSampleMavenBuild()).hasParent("com.example.infrastructure", "infrastructure-parent",
+				"1.0.0.RELEASE");
+	}
+
+	@Test
+	void hasParentWithWrongValue() {
+		assertThatExceptionOfType(AssertionError.class).isThrownBy(() -> assertThat(forSampleMavenBuild())
+				.hasParent("com.example.wrong", "infrastructure-parent", "1.0.0.RELEASE"));
+	}
+
+	@Test
+	void hasGroupId() {
+		assertThat(forSampleMavenBuild()).hasGroupId("com.example");
+	}
+
+	@Test
+	void hasGroupIdWithWrongValue() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forSampleMavenBuild()).hasGroupId("com.wrong"));
+	}
+
+	@Test
+	void hasArtifactId() {
+		assertThat(forSampleMavenBuild()).hasArtifactId("demo");
+	}
+
+	@Test
+	void hasArtifactIdWithWrongValue() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forSampleMavenBuild()).hasArtifactId("wrong"));
+	}
+
+	@Test
+	void hasVersion() {
+		assertThat(forSampleMavenBuild()).hasVersion("0.0.1-SNAPSHOT");
+	}
+
+	@Test
+	void hasVersionWithWrongValue() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forSampleMavenBuild()).hasVersion("1.0.0"));
+	}
+
+	@Test
+	void hasPackaging() {
+		assertThat(forMavenBuild("sample-packaging-pom.xml")).hasPackaging("zip");
+	}
+
+	@Test
+	void hasPackagingWithNoValue() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forSampleMavenBuild()).hasPackaging("jar"));
+	}
+
+	@Test
+	void hasName() {
+		assertThat(forSampleMavenBuild()).hasName("demo");
+	}
+
+	@Test
+	void hasNameWithWrongValue() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forSampleMavenBuild()).hasName("wrong"));
+	}
+
+	@Test
+	void hasDescription() {
+		assertThat(forSampleMavenBuild()).hasDescription("Demo project");
+	}
+
+	@Test
+	void hasDescriptionWithWrongValue() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forSampleMavenBuild()).hasDescription("Wrong description"));
+	}
+
+	@Test
+	void hasProperty() {
+		assertThat(forSampleMavenBuild()).hasProperty("acme.version", "Brussels.SR2");
+	}
+
+	@Test
+	void hasPropertyWithWrongValue() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forSampleMavenBuild()).hasProperty("acme.version", "Wrong.SR2"));
+	}
+
+	@Test
+	void doesNotHaveProperty() {
+		assertThat(forSampleMavenBuild()).doesNotHaveProperty("unknown.version");
+	}
+
+	@Test
+	void doesNotHavePropertyWithExistingProperty() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forSampleMavenBuild()).doesNotHaveProperty("acme.version"));
+	}
+
+	@Test
+	void hasDependenciesSize() {
+		assertThat(forSampleMavenBuild()).hasDependenciesSize(2);
+	}
+
+	@Test
+	void hasDependenciesSizeWithWrongSize() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forSampleMavenBuild()).hasDependenciesSize(3));
+	}
+
+	@Test
+	void hasDependency() {
+		assertThat(forSampleMavenBuild()).hasDependency("com.example.acme", "library");
+	}
+
+	@Test
+	void hasDependencyWithWrongScope() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forSampleMavenBuild()).hasDependency("com.example.acme", "library-test"));
+	}
+
+	@Test
+	void hasDependencyWithVersion() {
+		assertThat(forMavenBuild("sample-dependency-version-pom.xml")).hasDependency("com.example.acme", "library",
+				"1.2.0");
+	}
+
+	@Test
+	void hasDependencyWithVersionWithWrongVersion() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forMavenBuild("sample-dependency-version-pom.xml"))
+						.hasDependency("com.example.acme", "library", "1.3.0"));
+	}
+
+	@Test
+	void hasDependencyWithVersionAndScope() {
+		assertThat(forMavenBuild("sample-dependency-version-pom.xml")).hasDependency("com.example.acme", "library-test",
+				"1.3.0", "test");
+	}
+
+	@Test
+	void hasDependencyWithVersionAndScopeWithWrongScope() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forMavenBuild("sample-dependency-version-pom.xml"))
+						.hasDependency("com.example.acme", "library-test", "1.3.0", "runtime"));
+	}
+
+	@Test
+	void doesNotHaveDependencyArtifactId() {
+		assertThat(forSampleMavenBuild()).doesNotHaveDependency("com.example.acme", "wrong");
+	}
+
+	@Test
+	void doesNotHaveDependencyGroupId() {
+		assertThat(forSampleMavenBuild()).doesNotHaveDependency("com.example.wrong", "library");
+	}
+
+	@Test
+	void doesNotHaveDependencyWithMatchingDependency() {
+		assertThatExceptionOfType(AssertionError.class).isThrownBy(
+				() -> assertThat(forSampleMavenBuild()).doesNotHaveDependency("com.example.acme", "library"));
+	}
+
+	@Test
+	void hasBomsSize() {
+		assertThat(forSampleMavenBuild()).hasBomsSize(1);
+	}
+
+	@Test
+	void hasBomsSizeWithWrongSize() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forSampleMavenBuild()).hasBomsSize(3));
+	}
+
+	@Test
+	void hasBom() {
+		assertThat(forSampleMavenBuild()).hasBom("com.example.acme", "library-bom", "${acme.version}");
+	}
+
+	@Test
+	void hasBomWithWrongGroupId() {
+		assertThatExceptionOfType(AssertionError.class).isThrownBy(
+				() -> assertThat(forSampleMavenBuild()).hasBom("com.example.wrong", "library-bom", "${acme.version}"));
+	}
+
+	@Test
+	void hasBomWithWrongArtifactId() {
+		assertThatExceptionOfType(AssertionError.class).isThrownBy(
+				() -> assertThat(forSampleMavenBuild()).hasBom("com.example.acme", "library-wrong", "${acme.version}"));
+	}
+
+	@Test
+	void hasBomWithWrongVersion() {
+		assertThatExceptionOfType(AssertionError.class).isThrownBy(
+				() -> assertThat(forSampleMavenBuild()).hasBom("com.example.acme", "library-bom", "${wrong.version}"));
+	}
+
+	@Test
+	void hasRepositoriesSize() {
+		assertThat(forMavenBuild("sample-repositories-pom.xml")).hasRepositoriesSize(2);
+	}
+
+	@Test
+	void hasRepositoriesSizeWithNoRepository() {
+		assertThat(forSampleMavenBuild()).hasRepositoriesSize(0);
+	}
+
+	@Test
+	void hasRepositoriesSizeWrongSize() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forMavenBuild("sample-repositories-pom.xml")).hasRepositoriesSize(3));
+	}
+
+	@Test
+	void hasRepository() {
+		assertThat(forMavenBuild("sample-repositories-pom.xml")).hasRepository("acme-milestones", "Acme Milestones",
+				"https://repo.example.com/milestone", false);
+	}
+
+	@Test
+	void hasRepositoryWithSnapshots() {
+		assertThat(forMavenBuild("sample-repositories-pom.xml")).hasRepository("acme-snapshots", "Acme Snapshots",
+				"https://repo.example.com/snapshot", true);
+	}
+
+	@Test
+	void hasRepositoryWithWrongId() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forMavenBuild("sample-repositories-pom.xml")).hasRepository("acme-wrong",
+						"Acme Milestones", "https://repo.example.com/milestone", false));
+	}
+
+	@Test
+	void hasRepositoryWithWrongName() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forMavenBuild("sample-repositories-pom.xml"))
+						.hasRepository("acme-milestones", "Acme Wrong", "https://repo.example.com/milestone", false));
+	}
+
+	@Test
+	void hasRepositoryWithWrongUrl() {
+		assertThatExceptionOfType(AssertionError.class).isThrownBy(
+				() -> assertThat(forMavenBuild("sample-repositories-pom.xml")).hasRepository("acme-milestones",
+						"Acme Milestones", "https://repo.wrong.com/milestone", false));
+	}
+
+	@Test
+	void hasRepositoryWithWrongSnapshotFlag() {
+		assertThatExceptionOfType(AssertionError.class).isThrownBy(
+				() -> assertThat(forMavenBuild("sample-repositories-pom.xml")).hasRepository("acme-milestones",
+						"Acme Milestones", "https://repo.example.com/milestone", true));
+	}
+
+	private AssertProvider<MavenBuildAssert> forSampleMavenBuild() {
+		return forMavenBuild("sample-pom.xml");
+	}
+
+	private AssertProvider<MavenBuildAssert> forMavenBuild(String name) {
+		try (InputStream in = new ClassPathResource("project/build/maven/" + name).getInputStream()) {
+			String content = StreamUtils.copyToString(in, StandardCharsets.UTF_8);
+			return () -> new MavenBuildAssert(content);
+		}
+		catch (IOException ex) {
+			throw new IllegalStateException("No content found at " + name, ex);
+		}
+	}
+
+}

initializr-generator-test/src/test/java/io/spring/initializr/generator/test/io/TextAssertTests.java

@@ -0,0 +1,121 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.generator.test.io;
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+
+import org.assertj.core.api.AssertProvider;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+import org.springframework.core.io.Resource;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
+import static org.mockito.BDDMockito.given;
+import static org.mockito.Mockito.mock;
+
+/**
+ * Tests for {@link TextAssert}.
+ *
+ * @author Stephane Nicoll
+ */
+class TextAssertTests {
+
+	@Test
+	void sameContentAsWithNonReadableResource() {
+		Resource resource = mock(Resource.class);
+		given(resource.isReadable()).willReturn(false);
+		given(resource.toString()).willReturn("project/does-not-exist");
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forContent("Hello")).hasSameContentAs(resource))
+				.withMessageContaining("project/does-not-exist");
+	}
+
+	@Test
+	void sameContentAsWithNonReliableResource() throws IOException {
+		Resource resource = mock(Resource.class);
+		given(resource.isReadable()).willReturn(true);
+		given(resource.getInputStream()).willThrow(new IOException("Test exception"));
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forContent("Hello")).hasSameContentAs(resource))
+				.withMessageContaining("Cannot read expected content");
+	}
+
+	@Test
+	void sameContentAsWithMatchingResource() throws IOException {
+		assertThat(forContent("Hello")).hasSameContentAs(createResource("Hello"));
+	}
+
+	@Test
+	void sameContentAsWithMatchingResourceAndDifferentNewLinesInTarget() throws IOException {
+		assertThat(forContent("Hello\nWorld")).hasSameContentAs(createResource("Hello\r\nWorld"));
+	}
+
+	@Test
+	void sameContentAsWithMatchingResourceAndDifferentNewLinesInSource() throws IOException {
+		assertThat(forContent("Hello\r\nWorld")).hasSameContentAs(createResource("Hello\nWorld"));
+	}
+
+	@Test
+	void sameContentAsWithNonMatchingResource() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forContent("Test")).hasSameContentAs(createResource("Hello")))
+				.withMessageContaining("Test").withMessageContaining("Hello");
+	}
+
+	@Test
+	void sameContentAsWithFile(@TempDir Path dir) throws IOException {
+		Path file = Files.createFile(dir.resolve("hello.txt"));
+		try (PrintWriter writer = new PrintWriter(Files.newBufferedWriter(file))) {
+			writer.println("Test");
+		}
+		assertThat(forContent(file)).hasSameContentAs(createResource("Test"));
+	}
+
+	@Test
+	void sameContentAsWithFileAndNonMatchingResource(@TempDir Path dir) throws IOException {
+		Path file = Files.createFile(dir.resolve("hello.txt"));
+		try (PrintWriter writer = new PrintWriter(Files.newBufferedWriter(file))) {
+			writer.println("Test");
+		}
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forContent(file)).hasSameContentAs(createResource("Hello")))
+				.withMessageContaining("Test").withMessageContaining("Hello").withMessageContaining(file.toString());
+	}
+
+	private AssertProvider<TextAssert> forContent(String content) {
+		return () -> new TextAssert(content);
+	}
+
+	private AssertProvider<TextAssert> forContent(Path file) {
+		return () -> new TextAssert(file);
+	}
+
+	private Resource createResource(String content) throws IOException {
+		Resource resource = mock(Resource.class);
+		given(resource.isReadable()).willReturn(true);
+		given(resource.getInputStream()).willReturn(new ByteArrayInputStream(content.getBytes(StandardCharsets.UTF_8)));
+		return resource;
+	}
+
+}

initializr-generator-test/src/test/java/io/spring/initializr/generator/test/project/JvmModuleAssertTests.java

@@ -0,0 +1,154 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.generator.test.project;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.StandardOpenOption;
+
+import io.spring.initializr.generator.language.java.JavaLanguage;
+import org.assertj.core.api.AssertProvider;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+import org.springframework.util.FileCopyUtils;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
+
+/**
+ * Tests for {@link JvmModuleAssert}.
+ *
+ * @author Stephane Nicoll
+ */
+class JvmModuleAssertTests {
+
+	private static final JavaLanguage JAVA_LANGUAGE = new JavaLanguage();
+
+	@Test
+	void hasMainPackage(@TempDir Path root) throws IOException {
+		Files.createDirectories(root.resolve("src/main/java/com/example"));
+		assertThat(forJavaProject(root)).hasMainPackage("com.example");
+	}
+
+	@Test
+	void hasMainSource(@TempDir Path root) throws IOException {
+		createFile(root, "src/main/java/com/example/Test.java");
+		assertThat(forJavaProject(root)).hasMainSource("com.example", "Test");
+	}
+
+	@Test
+	void hasMainSourceWithNonMatchingExtension(@TempDir Path root) throws IOException {
+		createFile(root, "src/main/java/com/example/Test.other");
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forJavaProject(root)).hasMainSource("com.example", "Test"))
+				.withMessageContaining("Test").withMessageContaining("com.example").withMessageContaining("Test.java")
+				.withMessageContaining("com.example").withMessageContaining("src/main/java/com/example/Test.java");
+	}
+
+	@Test
+	void hasMainSourceWithNonMatchingSourceDir(@TempDir Path root) throws IOException {
+		createFile(root, "src/main/groovy/com/example/Test.java");
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forJavaProject(root)).hasMainSource("com.example", "Test"))
+				.withMessageContaining("Test.java").withMessageContaining("com.example")
+				.withMessageContaining("src/main/java/com/example/Test.java");
+	}
+
+	@Test
+	void mainSource(@TempDir Path root) throws IOException {
+		createFileFrom("import com.example.Test;", root.resolve("src/main/java/com/acme/Test.java"));
+		assertThat(forJavaProject(root)).mainSource("com.acme", "Test").containsOnlyOnce("import");
+	}
+
+	@Test
+	void mainSourceWithMissingSource(@TempDir Path root) {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forJavaProject(root)).mainSource("com.acme", "Test"));
+	}
+
+	@Test
+	void hasMainResource(@TempDir Path root) throws IOException {
+		createFile(root, "src/main/resources/project/sample.xml");
+		assertThat(forJavaProject(root)).hasMainResource("project/sample.xml");
+	}
+
+	@Test
+	void hasMainResourceWithMissingResource(@TempDir Path root) {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forJavaProject(root)).hasMainResource("project/sample.xml"));
+	}
+
+	@Test
+	void hasTestPackage(@TempDir Path root) throws IOException {
+		Files.createDirectories(root.resolve("src/test/java/com/example"));
+		assertThat(forJavaProject(root)).hasTestPackage("com.example");
+	}
+
+	@Test
+	void hasTestSource(@TempDir Path root) throws IOException {
+		createFile(root, "src/test/java/com/example/Test.java");
+		assertThat(forJavaProject(root)).hasTestSource("com.example", "Test");
+	}
+
+	@Test
+	void hasTestSourceWithNonMatchingExtension(@TempDir Path root) throws IOException {
+		createFile(root, "src/test/java/com/example/Test.other");
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forJavaProject(root)).hasTestSource("com.example", "Test"))
+				.withMessageContaining("Test").withMessageContaining("com.example").withMessageContaining("Test.java")
+				.withMessageContaining("com.example").withMessageContaining("src/test/java/com/example/Test.java");
+	}
+
+	@Test
+	void hasTestSourceWithNonMatchingSourceDir(@TempDir Path root) throws IOException {
+		createFile(root, "src/test/groovy/com/example/Test.java");
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forJavaProject(root)).hasTestSource("com.example", "Test"))
+				.withMessageContaining("Test.java").withMessageContaining("com.example")
+				.withMessageContaining("src/test/java/com/example/Test.java");
+	}
+
+	@Test
+	void testSource(@TempDir Path root) throws IOException {
+		createFileFrom("@Test", root.resolve("src/test/java/com/acme/DemoTests.java"));
+		assertThat(forJavaProject(root)).testSource("com.acme", "DemoTests").containsOnlyOnce("@Test");
+	}
+
+	@Test
+	void testSourceWithMissingSource(@TempDir Path root) {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forJavaProject(root)).testSource("com.acme", "DemoTests"));
+	}
+
+	private AssertProvider<AbstractJvmModuleAssert> forJavaProject(Path root) {
+		return () -> new JvmModuleAssert(root, JAVA_LANGUAGE, "java");
+	}
+
+	private void createFile(Path root, String path) throws IOException {
+		Path target = root.resolve(path);
+		Files.createDirectories(target.getParent());
+		Files.createFile(target);
+	}
+
+	private void createFileFrom(String content, Path target) throws IOException {
+		Files.createDirectories(target.getParent());
+		FileCopyUtils.copy(content, Files.newBufferedWriter(target, StandardOpenOption.CREATE));
+	}
+
+}

initializr-generator-test/src/test/java/io/spring/initializr/generator/test/project/ModuleAssertTests.java

@@ -0,0 +1,246 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.generator.test.project;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.StandardOpenOption;
+
+import io.spring.initializr.generator.language.java.JavaLanguage;
+import org.assertj.core.api.AssertProvider;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+import org.springframework.core.io.ClassPathResource;
+import org.springframework.core.io.Resource;
+import org.springframework.util.FileCopyUtils;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
+
+/**
+ * Tests for {@link ModuleAssert}.
+ *
+ * @author Stephane Nicoll
+ */
+class ModuleAssertTests {
+
+	@Test
+	void containDirectories(@TempDir Path dir) throws IOException {
+		createDirectories(dir, "test", "test/another", "another");
+		assertThat(forDirectory(dir)).containsDirectories("test", "test/another");
+	}
+
+	@Test
+	void containDirectoriesWithMissingDirectory(@TempDir Path dir) throws IOException {
+		createDirectories(dir, "test", "test/another", "another");
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forDirectory(dir)).containsDirectories("test", "wrong"));
+	}
+
+	@Test
+	void doesNotContainDirectories(@TempDir Path dir) throws IOException {
+		createDirectories(dir, "test", "test/another");
+		assertThat(forDirectory(dir)).doesNotContainDirectories("another", "test/something");
+	}
+
+	@Test
+	void doesNotContainDirectoriesWithExistingDirectory(@TempDir Path dir) throws IOException {
+		createDirectories(dir, "test", "test/another");
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forDirectory(dir)).doesNotContainDirectories("another", "test/another"));
+	}
+
+	@Test
+	void containFiles(@TempDir Path dir) throws IOException {
+		createFiles(dir, "test.xml", "src/Test.java", "another");
+		assertThat(forDirectory(dir)).containsFiles("src/Test.java", "another");
+	}
+
+	@Test
+	void containFilesWithMissingFile(@TempDir Path dir) throws IOException {
+		createFiles(dir, "test.xml", "src/Test.java", "another");
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forDirectory(dir)).containsFiles("test.xml", "wrong"));
+	}
+
+	@Test
+	void doesNotContainFiles(@TempDir Path dir) throws IOException {
+		createFiles(dir, "test.xml", "src/Test.java");
+		assertThat(forDirectory(dir)).doesNotContainFiles("another", "test/Another.java");
+	}
+
+	@Test
+	void doesNotContainFilesWithExistingFile(@TempDir Path dir) throws IOException {
+		createFiles(dir, "test.xml", "src/Test.java");
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forDirectory(dir)).doesNotContainFiles("another", "src/Test.java"));
+	}
+
+	@Test
+	void filePaths(@TempDir Path dir) throws IOException {
+		createFiles(dir, "src/One.java", "src/com/example/Two.java", "pom.xml", ".gitignore");
+		createDirectories(dir, "test/unrelated");
+		assertThat(forDirectory(dir)).filePaths().containsOnly("src/One.java", "src/com/example/Two.java", "pom.xml",
+				".gitignore");
+	}
+
+	@Test
+	void file(@TempDir Path dir) throws IOException {
+		createFiles(dir, "some/file/here.txt");
+		assertThat(forDirectory(dir)).file("some/file/here.txt").isEqualTo(dir.resolve("some/file/here.txt"));
+	}
+
+	@Test
+	void fileWithMissingFile(@TempDir Path dir) {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forDirectory(dir)).file("som/file/does-not-exist.txt"));
+	}
+
+	@Test
+	void textFile(@TempDir Path dir) throws IOException {
+		createFileFrom(new ClassPathResource("project/build/maven/sample-pom.xml"), dir.resolve("test.xml"));
+		assertThat(forDirectory(dir)).textFile("test.xml").contains("<dependencies>", "<version>");
+	}
+
+	@Test
+	void textFileWithMissingFile(@TempDir Path dir) {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forDirectory(dir)).textFile("som/file/does-not-exist.txt"));
+	}
+
+	@Test
+	void asJavaProject(@TempDir Path dir) throws IOException {
+		createFiles(dir, "src/main/java/com/example/Test.java");
+		assertThat(forDirectory(dir)).asJvmModule(new JavaLanguage(), "java").hasMainPackage("com.example")
+				.hasMainSource("com.example", "Test");
+	}
+
+	@Test
+	void hasMavenBuild(@TempDir Path dir) throws IOException {
+		createFiles(dir, "pom.xml");
+		assertThat(forDirectory(dir)).hasMavenBuild();
+	}
+
+	@Test
+	void hasMavenBuildWithMissingPomFile(@TempDir Path dir) throws IOException {
+		createFiles(dir, "pom.wrong");
+		assertThatExceptionOfType(AssertionError.class).isThrownBy(() -> assertThat(forDirectory(dir)).hasMavenBuild());
+	}
+
+	@Test
+	void hasMavenWrapper(@TempDir Path dir) throws IOException {
+		createFiles(dir, "mvnw", "mvnw.cmd", ".mvn/wrapper/maven-wrapper.properties", ".mvn/wrapper/maven-wrapper.jar");
+		assertThat(forDirectory(dir)).hasMavenWrapper();
+	}
+
+	@Test
+	void hasMavenWrapperWithMissingScript(@TempDir Path dir) throws IOException {
+		createFiles(dir, ".mvn/wrapper/maven-wrapper.properties", ".mvn/wrapper/maven-wrapper.jar");
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forDirectory(dir)).hasMavenWrapper());
+	}
+
+	@Test
+	void hasMavenWrapperWithMissingDotMvnDir(@TempDir Path dir) throws IOException {
+		createFiles(dir, "mvnw", "mvnw.cmd");
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forDirectory(dir)).hasMavenWrapper());
+	}
+
+	@Test
+	void mavenBuild(@TempDir Path dir) throws IOException {
+		createFileFrom(new ClassPathResource("project/build/maven/sample-pom.xml"), dir.resolve("pom.xml"));
+		assertThat(forDirectory(dir)).mavenBuild().hasGroupId("com.example").hasArtifactId("demo");
+	}
+
+	@Test
+	void mavenBuildWithMissingPomFile(@TempDir Path dir) {
+		assertThatExceptionOfType(AssertionError.class).isThrownBy(() -> assertThat(forDirectory(dir)).mavenBuild());
+	}
+
+	@Test
+	void hasGroovyDslGradleBuild(@TempDir Path dir) throws IOException {
+		createFiles(dir, "build.gradle");
+		assertThat(forDirectory(dir)).hasGroovyDslGradleBuild();
+	}
+
+	@Test
+	void hasGroovyDslGradleBuildWithMissingBuildFile(@TempDir Path dir) throws IOException {
+		createFiles(dir, "build.wrong");
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forDirectory(dir)).hasGroovyDslGradleBuild());
+	}
+
+	@Test
+	void hasGradleWrapper(@TempDir Path dir) throws IOException {
+		createFiles(dir, "gradlew", "gradlew.bat", "gradle/wrapper/gradle-wrapper.properties",
+				"gradle/wrapper/gradle-wrapper.jar");
+		assertThat(forDirectory(dir)).hasGradleWrapper();
+	}
+
+	@Test
+	void hasGradleWrapperWithMissingScript(@TempDir Path dir) throws IOException {
+		createFiles(dir, "gradle/wrapper/gradle-wrapper.properties", "gradle/wrapper/gradle-wrapper.jar");
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forDirectory(dir)).hasGradleWrapper());
+	}
+
+	@Test
+	void hasGradleWrapperWithMissingGradleDir(@TempDir Path dir) throws IOException {
+		createFiles(dir, "gradlew", "gradlew.bat");
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forDirectory(dir)).hasGradleWrapper());
+	}
+
+	@Test
+	void groovyDslGradleBuild(@TempDir Path dir) throws IOException {
+		createFileFrom(new ClassPathResource("project/build/gradle/sample-build.gradle"), dir.resolve("build.gradle"));
+		assertThat(forDirectory(dir)).groovyDslGradleBuild().hasVersion("0.0.1-SNAPSHOT").hasSourceCompatibility("1.8");
+	}
+
+	@Test
+	void groovyDslGradleBuildWithMissingBuildFile(@TempDir Path dir) {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forDirectory(dir)).groovyDslGradleBuild());
+	}
+
+	private AssertProvider<ModuleAssert> forDirectory(Path projectDirectory) {
+		return () -> new ModuleAssert(projectDirectory);
+	}
+
+	private void createDirectories(Path dir, String... directories) throws IOException {
+		for (String directory : directories) {
+			Files.createDirectories(dir.resolve(directory));
+		}
+	}
+
+	private void createFiles(Path dir, String... files) throws IOException {
+		for (String file : files) {
+			Path path = dir.resolve(file);
+			Files.createDirectories(path.getParent());
+			Files.createFile(path);
+		}
+	}
+
+	private void createFileFrom(Resource from, Path target) throws IOException {
+		Files.createDirectories(target.getParent());
+		FileCopyUtils.copy(from.getInputStream(), Files.newOutputStream(target, StandardOpenOption.CREATE));
+	}
+
+}

initializr-generator-test/src/test/java/io/spring/initializr/generator/test/project/ProjectGeneratorTests.java

@@ -91,9 +91,8 @@ class ProjectGeneratorTests {
 						Files.createFile(subDir.resolve("Test.src"));
 					});
 				});
-		ProjectStructure projectStructure = tester.generate(new ProjectDescription());
-		assertThat(projectStructure.getRelativePathsOfProjectFiles()).containsOnly("test.text",
-				"src/main/test/Test.src");
+		ProjectStructure project = tester.generate(new ProjectDescription());
+		assertThat(project).filePaths().containsOnly("test.text", "src/main/test/Test.src");
 	}
 
 	private static class TestProjectDescriptionCustomizer implements ProjectDescriptionCustomizer {

initializr-generator-test/src/test/java/io/spring/initializr/generator/test/project/ProjectStructureTests.java

@@ -0,0 +1,58 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.generator.test.project;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+
+/**
+ * Tests for {@link ProjectStructure}.
+ *
+ * @author Stephane Nicoll
+ */
+class ProjectStructureTests {
+
+	@Test
+	void resolveModule(@TempDir Path dir) throws IOException {
+		Path moduleDir = dir.resolve("test");
+		Files.createDirectories(moduleDir);
+		ProjectStructure module = new ProjectStructure(dir).resolveModule("test");
+		assertThat(module).isNotNull();
+		assertThat(module.getProjectDirectory()).isEqualTo(moduleDir);
+	}
+
+	@Test
+	void resolveModuleWithFile(@TempDir Path dir) throws IOException {
+		Files.createFile(dir.resolve("test"));
+		assertThatIllegalArgumentException().isThrownBy(() -> new ProjectStructure(dir).resolveModule("test"));
+	}
+
+	@Test
+	void resolveModuleWithNonExistingPath(@TempDir Path dir) {
+		Path test = dir.resolve("test");
+		assertThat(test).doesNotExist();
+		assertThatIllegalArgumentException().isThrownBy(() -> new ProjectStructure(dir).resolveModule("test"));
+	}
+
+}

initializr-generator-test/src/test/resources/project/build/gradle/sample-build.gradle

@@ -0,0 +1,28 @@
+plugins {
+	id 'com.example' version '1.0.0.RELEASE'
+	id 'java'
+}
+
+group = 'com.example'
+version = '0.0.1-SNAPSHOT'
+sourceCompatibility = '1.8'
+
+repositories {
+	mavenCentral()
+}
+
+ext {
+	set('acmeVersion', "Brussels.SR2")
+}
+
+dependencies {
+	implementation 'com.example.acme:library'
+	testImplementation 'com.example.acme:library-test'
+}
+
+dependencyManagement {
+	imports {
+		mavenBom "com.example.acme:library-bom:${acmeVersion}"
+	}
+}
+

initializr-generator-test/src/test/resources/project/build/gradle/sample-settings.gradle

@@ -0,0 +1 @@
+rootProject.name = 'demo'

initializr-generator-test/src/test/resources/project/build/maven/sample-dependency-version-pom.xml

@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+		 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<groupId>com.example</groupId>
+	<artifactId>demo</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+
+	<dependencies>
+		<dependency>
+			<groupId>com.example.acme</groupId>
+			<artifactId>library</artifactId>
+			<version>1.2.0</version>
+		</dependency>
+
+		<dependency>
+			<groupId>com.example.acme</groupId>
+			<artifactId>library-test</artifactId>
+			<version>1.3.0</version>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+
+</project>

initializr-generator-test/src/test/resources/project/build/maven/sample-packaging-pom.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+		 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<groupId>com.example</groupId>
+	<artifactId>demo</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<packaging>zip</packaging>
+
+</project>

initializr-generator-test/src/test/resources/project/build/maven/sample-pom.xml

@@ -0,0 +1,57 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+		 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>com.example.infrastructure</groupId>
+		<artifactId>infrastructure-parent</artifactId>
+		<version>1.0.0.RELEASE</version>
+		<relativePath/> <!-- lookup parent from repository -->
+	</parent>
+	<groupId>com.example</groupId>
+	<artifactId>demo</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>demo</name>
+	<description>Demo project</description>
+
+	<properties>
+		<java.version>1.8</java.version>
+		<acme.version>Brussels.SR2</acme.version>
+	</properties>
+
+	<dependencies>
+		<dependency>
+			<groupId>com.example.acme</groupId>
+			<artifactId>library</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>com.example.acme</groupId>
+			<artifactId>library-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+
+	<dependencyManagement>
+		<dependencies>
+			<dependency>
+				<groupId>com.example.acme</groupId>
+				<artifactId>library-bom</artifactId>
+				<version>${acme.version}</version>
+				<type>pom</type>
+				<scope>import</scope>
+			</dependency>
+		</dependencies>
+	</dependencyManagement>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>com.example</groupId>
+				<artifactId>acme-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>

initializr-generator-test/src/test/resources/project/build/maven/sample-repositories-pom.xml

@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+		 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<groupId>com.example</groupId>
+	<artifactId>demo</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+
+	<repositories>
+		<repository>
+			<id>acme-milestones</id>
+			<name>Acme Milestones</name>
+			<url>https://repo.example.com/milestone</url>
+		</repository>
+		<repository>
+			<id>acme-snapshots</id>
+			<name>Acme Snapshots</name>
+			<url>https://repo.example.com/snapshot</url>
+			<snapshots>
+				<enabled>true</enabled>
+			</snapshots>
+		</repository>
+	</repositories>
+
+</project>

initializr-web/src/test/java/io/spring/initializr/web/AbstractInitializrIntegrationTests.java

@@ -34,7 +34,7 @@ import java.util.stream.Collectors;
 
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
-import io.spring.initializr.generator.test.project.ProjectAssert;
+import io.spring.initializr.generator.test.project.ProjectStructure;
 import io.spring.initializr.web.AbstractInitializrIntegrationTests.Config;
 import io.spring.initializr.web.mapper.InitializrMetadataVersion;
 import io.spring.initializr.web.support.InitializrMetadataUpdateStrategy;
@@ -145,29 +145,54 @@ public abstract class AbstractInitializrIntegrationTests {
 	}
 
 	/**
-	 * Return a {@link ProjectAssert} for the following archive content.
-	 * @param content the source content
-	 * @return a project assert
+	 * Assert that the specified {@link ProjectStructure} has a structure with default
+	 * settings, i.e. a Java-based project with the default package and maven build.
+	 * @param project the project structure to assert
 	 */
-	protected ProjectAssert zipProjectAssert(byte[] content) {
-		return projectAssert(content, ArchiveType.ZIP);
+	protected void assertDefaultProject(ProjectStructure project) {
+		assertDefaultJavaProject(project);
+		assertThat(project).containsFiles(".gitignore");
+		assertThat(project).hasMavenBuild().hasMavenWrapper().file("mvnw").isExecutable();
+	}
+
+	protected void assertDefaultJavaProject(ProjectStructure project) {
+		assertThat(project).containsFiles("src/main/java/com/example/demo/DemoApplication.java",
+				"src/test/java/com/example/demo/DemoApplicationTests.java",
+				"src/main/resources/application.properties");
+	}
+
+	protected void assertHasWebResources(ProjectStructure project) {
+		assertThat(project).containsDirectories("src/main/resources/templates", "src/main/resources/static");
+	}
+
+	protected void assertDoesNotHaveWebResources(ProjectStructure project) {
+		assertThat(project).doesNotContainDirectories("src/main/resources/templates", "src/main/resources/static");
 	}
 
 	/**
-	 * Return a {@link ProjectAssert} for the following TGZ archive.
+	 * Return a {@link ProjectStructure} for the following archive content.
 	 * @param content the source content
 	 * @return a project assert
 	 */
-	protected ProjectAssert tgzProjectAssert(byte[] content) {
-		return projectAssert(content, ArchiveType.TGZ);
+	protected ProjectStructure projectFromArchive(byte[] content) {
+		return getProjectStructure(content, ArchiveType.ZIP);
 	}
 
-	protected ProjectAssert downloadZip(String context) {
+	/**
+	 * Return a {@link ProjectStructure} for the following TGZ archive.
+	 * @param content the source content
+	 * @return a project assert
+	 */
+	protected ProjectStructure tgzProjectAssert(byte[] content) {
+		return getProjectStructure(content, ArchiveType.TGZ);
+	}
+
+	protected ProjectStructure downloadZip(String context) {
 		byte[] body = downloadArchive(context).getBody();
-		return zipProjectAssert(body);
+		return projectFromArchive(body);
 	}
 
-	protected ProjectAssert downloadTgz(String context) {
+	protected ProjectStructure downloadTgz(String context) {
 		byte[] body = downloadArchive(context).getBody();
 		return tgzProjectAssert(body);
 	}
@@ -200,7 +225,7 @@ public abstract class AbstractInitializrIntegrationTests {
 				responseType);
 	}
 
-	protected ProjectAssert projectAssert(byte[] content, ArchiveType archiveType) {
+	protected ProjectStructure getProjectStructure(byte[] content, ArchiveType archiveType) {
 		try {
 			Path archiveFile = writeArchive(content);
 			Path project = this.folder.resolve("project");
@@ -212,7 +237,7 @@ public abstract class AbstractInitializrIntegrationTests {
 				untar(archiveFile, project);
 				break;
 			}
-			return new ProjectAssert(project);
+			return new ProjectStructure(project);
 		}
 		catch (Exception ex) {
 			throw new IllegalStateException("Cannot unpack archive", ex);

initializr-web/src/test/java/io/spring/initializr/web/project/CommandLineExampleIntegrationTests.java

@@ -16,13 +16,17 @@
 
 package io.spring.initializr.web.project;
 
-import io.spring.initializr.generator.test.buildsystem.maven.PomAssert;
+import io.spring.initializr.generator.test.buildsystem.maven.MavenBuildAssert;
+import io.spring.initializr.generator.test.project.ProjectStructure;
+import io.spring.initializr.metadata.Dependency;
 import io.spring.initializr.web.AbstractInitializrControllerIntegrationTests;
 import org.junit.jupiter.api.Test;
 
 import org.springframework.http.ResponseEntity;
 import org.springframework.test.context.ActiveProfiles;
 
+import static org.assertj.core.api.Assertions.assertThat;
+
 /**
  * Validate that the "raw" HTTP commands that are described in the command-line help
  * works. If anything needs to be updated here, please double check the
@@ -36,29 +40,39 @@ class CommandLineExampleIntegrationTests extends AbstractInitializrControllerInt
 
 	@Test
 	void generateDefaultProject() {
-		downloadZip("/starter.zip").isJavaProject().isMavenProject().hasStaticAndTemplatesResources(false).pomAssert()
-				.hasSpringBootStarterRootDependency().hasSpringBootStarterTest().hasDependenciesCount(2);
+		ProjectStructure project = downloadZip("/starter.zip");
+		assertDefaultProject(project);
+		assertDoesNotHaveWebResources(project);
+		assertThat(project).mavenBuild().hasDependency(Dependency.createSpringBootStarter(""))
+				.hasDependency(Dependency.createSpringBootStarter("test", Dependency.SCOPE_TEST))
+				.hasDependenciesSize(2);
 	}
 
 	@Test
 	void generateWebProjectWithJava8() {
-		downloadZip("/starter.zip?dependencies=web&javaVersion=1.8").isJavaProject().isMavenProject()
-				.hasStaticAndTemplatesResources(true).pomAssert().hasJavaVersion("1.8")
-				.hasSpringBootStarterDependency("web").hasSpringBootStarterTest().hasDependenciesCount(2);
+		ProjectStructure project = downloadZip("/starter.zip?dependencies=web&javaVersion=1.8");
+		assertDefaultProject(project);
+		assertHasWebResources(project);
+		assertThat(project).mavenBuild().hasProperty("java.version", "1.8")
+				.hasDependency(Dependency.createSpringBootStarter("web"))
+				.hasDependency(Dependency.createSpringBootStarter("test", Dependency.SCOPE_TEST))
+				.hasDependenciesSize(2);
 	}
 
 	@Test
 	void generateWebDataJpaGradleProject() {
-		downloadTgz("/starter.tgz?dependencies=web,data-jpa&type=gradle-project&baseDir=my-dir").hasBaseDir("my-dir")
-				.isJavaProject().isGradleProject().hasStaticAndTemplatesResources(true).gradleBuildAssert()
-				.contains("spring-boot-starter-web").contains("spring-boot-starter-data-jpa");
+		ProjectStructure project = downloadTgz(
+				"/starter.tgz?dependencies=web,data-jpa&type=gradle-project&baseDir=my-dir").resolveModule("my-dir");
+		assertHasWebResources(project);
+		assertThat(project).groovyDslGradleBuild().contains("spring-boot-starter-web")
+				.contains("spring-boot-starter-data-jpa");
 	}
 
 	@Test
 	void generateMavenPomWithWarPackaging() {
 		ResponseEntity<String> response = getRestTemplate().getForEntity(createUrl("/pom.xml?packaging=war"),
 				String.class);
-		PomAssert pomAssert = new PomAssert(response.getBody());
+		MavenBuildAssert pomAssert = new MavenBuildAssert(response.getBody());
 		pomAssert.hasPackaging("war");
 	}
 

initializr-web/src/test/java/io/spring/initializr/web/project/MainControllerArchiveIntegrationTests.java

@@ -16,10 +16,10 @@
 
 package io.spring.initializr.web.project;
 
+import io.spring.initializr.generator.test.project.ProjectStructure;
 import io.spring.initializr.web.AbstractFullStackInitializrIntegrationTests;
 import org.junit.jupiter.api.Test;
 
-import org.springframework.http.ResponseEntity;
 import org.springframework.test.context.ActiveProfiles;
 
 /**
@@ -30,8 +30,8 @@ public class MainControllerArchiveIntegrationTests extends AbstractFullStackInit
 
 	@Test
 	void baseDirectorySeparatedBySpace() {
-		ResponseEntity<byte[]> entity = downloadArchive("/starter.zip?artifactId=demo&baseDir=demo trial");
-		zipProjectAssert(entity.getBody()).hasBaseDir("demo trial").hasExecutableFile("mvnw").isJavaProject();
+		ProjectStructure project = downloadZip("/starter.zip?artifactId=demo&baseDir=demo trial");
+		assertDefaultProject(project.resolveModule("demo trial"));
 	}
 
 }

initializr-web/src/test/java/io/spring/initializr/web/project/MainControllerDefaultsIntegrationTests.java

@@ -16,7 +16,7 @@
 
 package io.spring.initializr.web.project;
 
-import io.spring.initializr.generator.test.buildsystem.maven.PomAssert;
+import io.spring.initializr.generator.test.buildsystem.maven.MavenBuildAssert;
 import io.spring.initializr.web.AbstractInitializrControllerIntegrationTests;
 import org.junit.jupiter.api.Test;
 
@@ -33,7 +33,7 @@ class MainControllerDefaultsIntegrationTests extends AbstractInitializrControlle
 	@Test
 	void generateDefaultPom() {
 		String content = getRestTemplate().getForObject(createUrl("/pom.xml?style=web"), String.class);
-		PomAssert pomAssert = new PomAssert(content);
+		MavenBuildAssert pomAssert = new MavenBuildAssert(content);
 		pomAssert.hasGroupId("org.foo").hasArtifactId("foo-bar").hasVersion("1.2.4-SNAPSHOT")
 				.doesNotHaveNode("/project/packaging").hasName("FooBar").hasDescription("FooBar Project");
 	}

initializr-web/src/test/java/io/spring/initializr/web/project/MainControllerEnvIntegrationTests.java

@@ -18,7 +18,8 @@ package io.spring.initializr.web.project;
 
 import java.net.URI;
 
-import io.spring.initializr.generator.test.project.ProjectAssert;
+import io.spring.initializr.generator.test.project.ProjectStructure;
+import io.spring.initializr.metadata.Dependency;
 import io.spring.initializr.web.AbstractInitializrControllerIntegrationTests;
 import org.junit.jupiter.api.Test;
 
@@ -46,10 +47,15 @@ class MainControllerEnvIntegrationTests extends AbstractInitializrControllerInte
 
 	@Test
 	void generateProjectWithInvalidName() {
-		downloadZip("/starter.zip?style=data-jpa&name=Invalid")
-				.isJavaProject(ProjectAssert.DEFAULT_PACKAGE_NAME, "FooBarApplication").isMavenProject()
-				.hasStaticAndTemplatesResources(false).pomAssert().hasDependenciesCount(2)
-				.hasSpringBootStarterDependency("data-jpa").hasSpringBootStarterTest();
+		ProjectStructure project = downloadZip("/starter.zip?style=data-jpa&name=Invalid");
+		assertThat(project).containsFiles("src/main/java/com/example/demo/FooBarApplication.java",
+				"src/test/java/com/example/demo/FooBarApplicationTests.java");
+		assertThat(project).doesNotContainFiles("src/main/java/com/example/demo/DemoApplication.java",
+				"src/test/java/com/example/demo/DemoApplicationTests.java");
+		assertDoesNotHaveWebResources(project);
+		assertThat(project).mavenBuild().hasDependenciesSize(2)
+				.hasDependency(Dependency.createSpringBootStarter("data-jpa"))
+				.hasDependency(Dependency.createSpringBootStarter("test", Dependency.SCOPE_TEST));
 	}
 
 }

initializr-web/src/test/java/io/spring/initializr/web/project/MainControllerIntegrationTests.java

@@ -19,6 +19,7 @@ package io.spring.initializr.web.project;
 import java.net.URI;
 import java.net.URISyntaxException;
 
+import io.spring.initializr.generator.test.project.ProjectStructure;
 import io.spring.initializr.metadata.Dependency;
 import io.spring.initializr.web.AbstractInitializrControllerIntegrationTests;
 import io.spring.initializr.web.AbstractInitializrIntegrationTests;
@@ -49,22 +50,25 @@ class MainControllerIntegrationTests extends AbstractInitializrControllerIntegra
 	void simpleZipProject() {
 		ResponseEntity<byte[]> entity = downloadArchive("/starter.zip?style=web&style=jpa");
 		assertArchiveResponseHeaders(entity, MediaType.valueOf("application/zip"), "demo.zip");
-		zipProjectAssert(entity.getBody()).isJavaProject().hasFile(".gitignore").hasExecutableFile("mvnw")
-				.isMavenProject().hasStaticAndTemplatesResources(true).pomAssert().hasDependenciesCount(3)
-				.hasSpringBootStarterDependency("web").hasSpringBootStarterDependency("data-jpa") // alias
-																									// jpa
-																									// ->
-																									// data-jpa
-				.hasSpringBootStarterTest();
+		ProjectStructure project = projectFromArchive(entity.getBody());
+		assertDefaultProject(project);
+		assertHasWebResources(project);
+		assertThat(project).mavenBuild().hasDependenciesSize(3).hasDependency(Dependency.createSpringBootStarter("web"))
+				// alias: jpa -> data-jpa
+				.hasDependency(Dependency.createSpringBootStarter("data-jpa"))
+				.hasDependency(Dependency.createSpringBootStarter("test", Dependency.SCOPE_TEST));
+
 	}
 
 	@Test
 	void simpleTgzProject() {
 		ResponseEntity<byte[]> entity = downloadArchive("/starter.tgz?style=org.acme:foo");
 		assertArchiveResponseHeaders(entity, MediaType.valueOf("application/x-compress"), "demo.tar.gz");
-		tgzProjectAssert(entity.getBody()).isJavaProject().hasFile(".gitignore").hasExecutableFile("mvnw")
-				.isMavenProject().hasStaticAndTemplatesResources(false).pomAssert().hasDependenciesCount(2)
-				.hasDependency("org.acme", "foo", "1.3.5");
+		ProjectStructure project = tgzProjectAssert(entity.getBody());
+		assertDefaultProject(project);
+		assertDoesNotHaveWebResources(project);
+		assertThat(project).doesNotContainDirectories("src/main/resources/templates", "src/main/resources/static");
+		assertThat(project).mavenBuild().hasDependenciesSize(2).hasDependency("org.acme", "foo", "1.3.5");
 	}
 
 	private void assertArchiveResponseHeaders(ResponseEntity<byte[]> entity, MediaType contentType, String fileName) {
@@ -76,8 +80,10 @@ class MainControllerIntegrationTests extends AbstractInitializrControllerIntegra
 	@Test
 	void dependencyInRange() {
 		Dependency biz = Dependency.create("org.acme", "biz", "1.3.5", "runtime");
-		downloadTgz("/starter.tgz?style=org.acme:biz&bootVersion=2.2.1.RELEASE").isJavaProject().isMavenProject()
-				.hasStaticAndTemplatesResources(false).pomAssert().hasDependenciesCount(3).hasDependency(biz);
+		ProjectStructure project = downloadTgz("/starter.tgz?style=org.acme:biz&bootVersion=2.2.1.RELEASE");
+		assertDefaultProject(project);
+		assertDoesNotHaveWebResources(project);
+		assertThat(project).mavenBuild().hasDependenciesSize(3).hasDependency(biz);
 	}
 
 	@Test
@@ -92,44 +98,56 @@ class MainControllerIntegrationTests extends AbstractInitializrControllerIntegra
 
 	@Test
 	void noDependencyProject() {
-		downloadZip("/starter.zip").isJavaProject().isMavenProject().hasStaticAndTemplatesResources(false).pomAssert()
-				.hasDependenciesCount(2)
+		ProjectStructure project = downloadZip("/starter.zip");
+		assertDefaultProject(project);
+		assertDoesNotHaveWebResources(project);
+		assertThat(project).mavenBuild().hasDependenciesSize(2)
 				// the root dep is added if none is specified
-				.hasSpringBootStarterRootDependency().hasSpringBootStarterTest();
+				.hasDependency(Dependency.createSpringBootStarter(""))
+				.hasDependency(Dependency.createSpringBootStarter("test", Dependency.SCOPE_TEST));
 	}
 
 	@Test
 	void dependenciesIsAnAliasOfStyle() {
-		downloadZip("/starter.zip?dependencies=web&dependencies=jpa").isJavaProject().isMavenProject()
-				.hasStaticAndTemplatesResources(true).pomAssert().hasDependenciesCount(3)
-				.hasSpringBootStarterDependency("web").hasSpringBootStarterDependency("data-jpa") // alias
-																									// jpa
-																									// ->
-																									// data-jpa
-				.hasSpringBootStarterTest();
+		ProjectStructure project = downloadZip("/starter.zip?dependencies=web&dependencies=jpa");
+		assertDefaultProject(project);
+		assertHasWebResources(project);
+		assertThat(project).mavenBuild().hasDependenciesSize(3).hasDependency(Dependency.createSpringBootStarter("web"))
+				// alias: jpa -> data-jpa
+				.hasDependency(Dependency.createSpringBootStarter("data-jpa"))
+				.hasDependency(Dependency.createSpringBootStarter("test", Dependency.SCOPE_TEST));
 	}
 
 	@Test
 	void dependenciesIsAnAliasOfStyleCommaSeparated() {
-		downloadZip("/starter.zip?dependencies=web,jpa").isJavaProject().isMavenProject()
-				.hasStaticAndTemplatesResources(true).pomAssert().hasDependenciesCount(3)
-				.hasSpringBootStarterDependency("web").hasSpringBootStarterDependency("data-jpa") // alias
-																									// jpa
-																									// ->
-																									// data-jpa
-				.hasSpringBootStarterTest();
+		ProjectStructure project = downloadZip("/starter.zip?dependencies=web,jpa");
+		assertDefaultProject(project);
+		assertHasWebResources(project);
+		assertThat(project).mavenBuild().hasDependenciesSize(3).hasDependency(Dependency.createSpringBootStarter("web"))
+				// alias: jpa -> data-jpa
+				.hasDependency(Dependency.createSpringBootStarter("data-jpa"))
+				.hasDependency(Dependency.createSpringBootStarter("test", Dependency.SCOPE_TEST));
 	}
 
 	@Test
 	void kotlinRange() {
-		downloadZip("/starter.zip?style=web&language=kotlin&bootVersion=2.0.1.RELEASE").isKotlinProject()
-				.isMavenProject().pomAssert().hasDependenciesCount(4).hasProperty("kotlin.version", "1.1");
+		ProjectStructure project = downloadZip("/starter.zip?style=web&language=kotlin&bootVersion=2.0.1.RELEASE");
+		assertThat(project).containsFiles("src/main/kotlin/com/example/demo/DemoApplication.kt",
+				"src/test/kotlin/com/example/demo/DemoApplicationTests.kt",
+				"src/main/resources/application.properties");
+		assertThat(project).mavenBuild().hasDependenciesSize(4).hasProperty("kotlin.version", "1.1");
 	}
 
 	@Test
 	void gradleWarProject() {
-		downloadZip("/starter.zip?style=web&style=security&packaging=war&type=gradle-project").isJavaWarProject()
-				.isGradleProject();
+		ProjectStructure project = downloadZip(
+				"/starter.zip?style=web&style=security&packaging=war&type=gradle-project");
+		assertThat(project).hasGroovyDslGradleBuild().hasGradleWrapper();
+		assertThat(project).containsFiles("src/main/java/com/example/demo/DemoApplication.java",
+				"src/main/java/com/example/demo/ServletInitializer.java",
+				"src/test/java/com/example/demo/DemoApplicationTests.java",
+				"src/main/resources/application.properties");
+		assertHasWebResources(project);
 	}
 
 	@Test
@@ -226,13 +244,13 @@ class MainControllerIntegrationTests extends AbstractInitializrControllerIntegra
 	@Test
 	void curlCanStillDownloadZipArchive() {
 		ResponseEntity<byte[]> response = execute("/starter.zip", byte[].class, "curl/1.2.4", "*/*");
-		zipProjectAssert(response.getBody()).isMavenProject().isJavaProject();
+		assertDefaultProject(projectFromArchive(response.getBody()));
 	}
 
 	@Test
 	void curlCanStillDownloadTgzArchive() {
 		ResponseEntity<byte[]> response = execute("/starter.tgz", byte[].class, "curl/1.2.4", "*/*");
-		tgzProjectAssert(response.getBody()).isMavenProject().isJavaProject();
+		assertDefaultProject(tgzProjectAssert(response.getBody()));
 	}
 
 	@Test

initializr-web/src/test/java/io/spring/initializr/web/project/ProjectGenerationDescriptionCustomizerTests.java

@@ -19,6 +19,7 @@ package io.spring.initializr.web.project;
 import io.spring.initializr.generator.language.java.JavaLanguage;
 import io.spring.initializr.generator.project.ProjectDescription;
 import io.spring.initializr.generator.project.ProjectDescriptionCustomizer;
+import io.spring.initializr.generator.test.project.ProjectStructure;
 import io.spring.initializr.generator.version.Version;
 import io.spring.initializr.web.AbstractInitializrControllerIntegrationTests;
 import io.spring.initializr.web.project.ProjectGenerationDescriptionCustomizerTests.ProjectDescriptionCustomizerConfiguration;
@@ -29,14 +30,19 @@ import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Import;
 import org.springframework.test.context.ActiveProfiles;
 
+import static org.assertj.core.api.Assertions.assertThat;
+
 @ActiveProfiles("test-default")
 @Import(ProjectDescriptionCustomizerConfiguration.class)
 class ProjectGenerationDescriptionCustomizerTests extends AbstractInitializrControllerIntegrationTests {
 
 	@Test
 	void projectDescriptionCustomizersAreInvoked() {
-		downloadZip("/starter.zip?bootVersion=2.0.4.RELEASE&javaVersion=1.8").isJavaProject().isMavenProject()
-				.pomAssert().hasSpringBootParent("2.2.3.RELEASE").hasProperty("java.version", "1.7");
+		ProjectStructure project = downloadZip("/starter.zip?bootVersion=2.0.4.RELEASE&javaVersion=1.8");
+		assertDefaultJavaProject(project);
+		assertThat(project).mavenBuild()
+				.hasParent("org.springframework.boot", "spring-boot-starter-parent", "2.2.3.RELEASE")
+				.hasProperty("java.version", "1.7");
 	}
 
 	@Configuration

initializr-web/src/test/java/io/spring/initializr/web/project/ProjectGenerationInvokerTests.java

@@ -27,9 +27,9 @@ import io.spring.initializr.generator.io.SimpleIndentStrategy;
 import io.spring.initializr.generator.io.template.MustacheTemplateRenderer;
 import io.spring.initializr.generator.project.ProjectDirectoryFactory;
 import io.spring.initializr.generator.test.InitializrMetadataTestBuilder;
-import io.spring.initializr.generator.test.buildsystem.gradle.GradleBuildAssert;
-import io.spring.initializr.generator.test.buildsystem.maven.PomAssert;
-import io.spring.initializr.generator.test.project.ProjectAssert;
+import io.spring.initializr.generator.test.buildsystem.gradle.GroovyDslGradleBuildAssert;
+import io.spring.initializr.generator.test.buildsystem.maven.MavenBuildAssert;
+import io.spring.initializr.generator.test.project.ProjectStructure;
 import io.spring.initializr.metadata.InitializrMetadata;
 import io.spring.initializr.metadata.InitializrMetadataProvider;
 import org.junit.jupiter.api.AfterEach;
@@ -87,7 +87,7 @@ public class ProjectGenerationInvokerTests {
 		request.setType("maven-project");
 		request.initialize(metadata);
 		ProjectGenerationResult result = this.invoker.invokeProjectStructureGeneration(request);
-		new ProjectAssert(result.getRootDirectory()).isJavaProject();
+		assertThat(new ProjectStructure(result.getRootDirectory())).hasMavenBuild();
 		Map<Path, List<Path>> tempFiles = (Map<Path, List<Path>>) ReflectionTestUtils.getField(this.invoker,
 				"temporaryFiles");
 		assertThat(tempFiles.get(result.getRootDirectory())).contains(result.getRootDirectory());
@@ -114,10 +114,10 @@ public class ProjectGenerationInvokerTests {
 		request.initialize(metadata);
 		byte[] bytes = this.invoker.invokeBuildGeneration(request);
 		String content = new String(bytes);
-		new PomAssert(content).hasGroupId(request.getGroupId()).hasArtifactId(request.getArtifactId())
+		new MavenBuildAssert(content).hasGroupId(request.getGroupId()).hasArtifactId(request.getArtifactId())
 				.hasVersion(request.getVersion()).doesNotHaveNode("/project/packaging").hasName(request.getName())
-				.hasDescription(request.getDescription()).hasJavaVersion(request.getJavaVersion())
-				.hasSpringBootParent(request.getBootVersion());
+				.hasDescription(request.getDescription()).hasProperty("java.version", request.getJavaVersion())
+				.hasParent("org.springframework.boot", "spring-boot-starter-parent", request.getBootVersion());
 		verifyProjectSuccessfulEventFor(request);
 	}
 
@@ -128,8 +128,9 @@ public class ProjectGenerationInvokerTests {
 		request.setType("gradle-project");
 		byte[] bytes = this.invoker.invokeBuildGeneration(request);
 		String content = new String(bytes);
-		new GradleBuildAssert(content).hasVersion(request.getVersion()).hasSpringBootPlugin(request.getBootVersion())
-				.hasJavaVersion(request.getJavaVersion());
+		new GroovyDslGradleBuildAssert(content).hasVersion(request.getVersion())
+				.hasPlugin("org.springframework.boot", request.getBootVersion())
+				.hasSourceCompatibility(request.getJavaVersion());
 		verifyProjectSuccessfulEventFor(request);
 	}