Correct Kotlin DSL syntax for adding and customizing configurations

Fixes gh-917

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

@@ -18,7 +18,6 @@ package io.spring.initializr.generator.spring.build.gradle;
 
 import io.spring.initializr.generator.buildsystem.DependencyScope;
 import io.spring.initializr.generator.buildsystem.gradle.GradleBuild;
-import io.spring.initializr.generator.buildsystem.gradle.GradleBuild.ConfigurationCustomization;
 import org.junit.jupiter.api.Test;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -37,11 +36,7 @@ class GradleConfigurationBuildCustomizerTests {
 		build.dependencies().add("servlet", "javax.servlet", "servlet-api",
 				DependencyScope.PROVIDED_RUNTIME);
 		customize(build);
-		assertThat(build.getConfigurationCustomizations())
+		assertThat(build.getConfigurations()).containsOnly("providedRuntime");
-				.containsOnlyKeys("providedRuntime");
-		ConfigurationCustomization providedRuntime = build
-				.getConfigurationCustomizations().get("providedRuntime");
-		assertThat(providedRuntime.getExtendsFrom()).isEmpty();
 	}
 
 	@Test

initializr-generator-spring/src/test/resources/project/gradle/annotation-processor-dependency-build.gradle.kts.gen

@@ -10,7 +10,7 @@ java.sourceCompatibility = JavaVersion.VERSION_1_8
 
 configurations {
 	compileOnly {
-		extendsFrom(configurations.annotationProcessor.get())
+		extendsFrom(annotationProcessor)
 	}
 }
 

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

@@ -50,6 +50,8 @@ public class GradleBuild extends Build {
 
 	private final List<String> appliedPlugins = new ArrayList<>();
 
+	private final List<String> configurations = new ArrayList<>();
+
 	private final Map<String, ConfigurationCustomization> configurationCustomizations = new LinkedHashMap<>();
 
 	private final Map<String, TaskCustomization> taskCustomizations = new LinkedHashMap<>();
@@ -122,14 +124,17 @@ public class GradleBuild extends Build {
 	}
 
 	public void addConfiguration(String configurationName) {
-		customizeConfiguration(configurationName, (configuration) -> {
+		this.configurations.add(configurationName);
-		});
 	}
 
 	public Map<String, ConfigurationCustomization> getConfigurationCustomizations() {
 		return Collections.unmodifiableMap(this.configurationCustomizations);
 	}
 
+	public List<String> getConfigurations() {
+		return Collections.unmodifiableList(this.configurations);
+	}
+
 	public Set<String> getImportedTypes() {
 		return Collections.unmodifiableSet(this.importedTypes);
 	}

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

@@ -85,18 +85,8 @@ public abstract class GradleBuildWriter {
 	protected abstract void writeJavaSourceCompatibility(IndentingWriter writer,
 			GradleBuild build);
 
-	private void writeConfigurations(IndentingWriter writer, GradleBuild build) {
+	protected abstract void writeConfigurations(IndentingWriter writer,
-		Map<String, ConfigurationCustomization> configurationCustomizations = build
+			GradleBuild build);
-				.getConfigurationCustomizations();
-		if (configurationCustomizations.isEmpty()) {
-			return;
-		}
-		writer.println("configurations {");
-		writer.indented(() -> configurationCustomizations.forEach((name,
-				customization) -> writeConfiguration(writer, name, customization)));
-		writer.println("}");
-		writer.println("");
-	}
 
 	protected abstract void writeConfiguration(IndentingWriter writer,
 			String configurationName,

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

@@ -24,6 +24,7 @@ import io.spring.initializr.generator.buildsystem.BillOfMaterials;
 import io.spring.initializr.generator.buildsystem.Dependency;
 import io.spring.initializr.generator.buildsystem.Dependency.Exclusion;
 import io.spring.initializr.generator.buildsystem.MavenRepository;
+import io.spring.initializr.generator.buildsystem.gradle.GradleBuild.ConfigurationCustomization;
 import io.spring.initializr.generator.io.IndentingWriter;
 import io.spring.initializr.generator.version.VersionProperty;
 import io.spring.initializr.generator.version.VersionReference;
@@ -93,15 +94,10 @@ public class GroovyDslGradleBuildWriter extends GradleBuildWriter {
 	@Override
 	protected void writeConfiguration(IndentingWriter writer, String configurationName,
 			GradleBuild.ConfigurationCustomization configurationCustomization) {
-		if (configurationCustomization.getExtendsFrom().isEmpty()) {
+		writer.println(configurationName + " {");
-			writer.println(configurationName);
+		writer.indented(() -> writer.println(String.format("extendsFrom %s",
-		}
+				String.join(", ", configurationCustomization.getExtendsFrom()))));
-		else {
+		writer.println("}");
-			writer.println(configurationName + " {");
-			writer.indented(() -> writer.println(String.format("extendsFrom %s",
-					String.join(", ", configurationCustomization.getExtendsFrom()))));
-			writer.println("}");
-		}
 	}
 
 	@Override
@@ -124,6 +120,24 @@ public class GroovyDslGradleBuildWriter extends GradleBuildWriter {
 		return String.format("set('%s', %s)", key, value);
 	}
 
+	@Override
+	protected void writeConfigurations(IndentingWriter writer, GradleBuild build) {
+		Map<String, ConfigurationCustomization> configurationCustomizations = build
+				.getConfigurationCustomizations();
+		List<String> configurations = build.getConfigurations();
+		if (configurations.isEmpty() && configurationCustomizations.isEmpty()) {
+			return;
+		}
+		writer.println("configurations {");
+		writer.indented(() -> {
+			configurations.forEach(writer::println);
+			configurationCustomizations.forEach((name,
+					customization) -> writeConfiguration(writer, name, customization));
+		});
+		writer.println("}");
+		writer.println("");
+	}
+
 	@Override
 	protected void writeDependency(IndentingWriter writer, Dependency dependency) {
 		String quoteStyle = determineQuoteStyle(dependency.getVersion());

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

@@ -117,7 +117,6 @@ public class KotlinDslGradleBuildWriter extends GradleBuildWriter {
 			writer.println(configurationName + " {");
 			writer.indented(() -> writer.println(String.format("extendsFrom(%s)",
 					configurationCustomization.getExtendsFrom().stream()
-							.map((c) -> "configurations." + c + ".get()")
 							.collect(Collectors.joining(", ")))));
 			writer.println("}");
 		}
@@ -131,6 +130,23 @@ public class KotlinDslGradleBuildWriter extends GradleBuildWriter {
 		return "maven { url = uri(\"" + repository.getUrl() + "\") }";
 	}
 
+	@Override
+	protected void writeConfigurations(IndentingWriter writer, GradleBuild build) {
+		Map<String, ConfigurationCustomization> configurationCustomizations = build
+				.getConfigurationCustomizations();
+		for (String configuration : build.getConfigurations()) {
+			writer.println("val " + configuration + " by configurations.creating");
+		}
+		if (configurationCustomizations.isEmpty()) {
+			return;
+		}
+		writer.println("configurations {");
+		writer.indented(() -> configurationCustomizations.forEach((name,
+				customization) -> writeConfiguration(writer, name, customization)));
+		writer.println("}");
+		writer.println("");
+	}
+
 	@Override
 	protected void writeDependency(IndentingWriter writer, Dependency dependency) {
 		String version = determineVersion(dependency.getVersion());

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

@@ -290,35 +290,33 @@ class KotlinDslGradleBuildWriterTests {
 		GradleBuild build = new GradleBuild();
 		build.addConfiguration("developmentOnly");
 		List<String> lines = generateBuild(build);
-		assertThat(lines).containsSequence("configurations {", "    developmentOnly",
+		assertThat(lines)
-				"}");
+				.containsSequence("val developmentOnly by configurations.creating");
 	}
 
 	@Test
 	void gradleBuildWithConfigurationCustomization() throws Exception {
 		GradleBuild build = new GradleBuild();
-		build.customizeConfiguration("developmentOnly",
+		build.customizeConfiguration("runtimeClasspath",
-				(configuration) -> configuration.extendsFrom("compile"));
+				(configuration) -> configuration.extendsFrom("custom1"));
-		build.customizeConfiguration("developmentOnly",
+		build.customizeConfiguration("runtimeClasspath",
-				(configuration) -> configuration.extendsFrom("testCompile"));
+				(configuration) -> configuration.extendsFrom("custom2"));
 		List<String> lines = generateBuild(build);
-		assertThat(lines).containsSequence("configurations {", "    developmentOnly {",
+		assertThat(lines).containsSequence("configurations {", "    runtimeClasspath {",
-				"        extendsFrom(configurations.compile.get(), configurations.testCompile.get())",
+				"        extendsFrom(custom1, custom2)", "    }", "}");
-				"    }", "}");
 	}
 
 	@Test
 	void gradleBuildWithConfigurationCustomizations() throws Exception {
 		GradleBuild build = new GradleBuild();
-		build.customizeConfiguration("developmentOnly",
+		build.customizeConfiguration("runtimeClasspath",
-				(configuration) -> configuration.extendsFrom("compile"));
+				(configuration) -> configuration.extendsFrom("custom1"));
-		build.customizeConfiguration("testOnly",
+		build.customizeConfiguration("testRuntimeClasspath",
-				(configuration) -> configuration.extendsFrom("testCompile"));
+				(configuration) -> configuration.extendsFrom("custom2"));
 		List<String> lines = generateBuild(build);
-		assertThat(lines).containsSequence("configurations {", "    developmentOnly {",
+		assertThat(lines).containsSequence("configurations {", "    runtimeClasspath {",
-				"        extendsFrom(configurations.compile.get())", "    }",
+				"        extendsFrom(custom1)", "    }", "    testRuntimeClasspath {",
-				"    testOnly {", "        extendsFrom(configurations.testCompile.get())",
+				"        extendsFrom(custom2)", "    }", "}");
-				"    }", "}");
 	}
 
 	@Test