Add doesNotHaveBom test assertion

Closes gh-1074

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2020 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.
@@ -250,6 +250,20 @@ public class MavenBuildAssert extends AbstractTextAssert<MavenBuildAssert> {
 		return this;
 	}
 
+	/**
+	 * Assert that {@code pom.xml} does not define the specified bom.
+	 * @param groupId the groupId of the bom
+	 * @param artifactId the artifactId of the bom
+	 * @return {@code this} assertion object
+	 */
+	public MavenBuildAssert doesNotHaveBom(String groupId, String artifactId) {
+		this.pom.nodesAtPath("/project/dependencyManagement/dependencies/dependency").noneMatch((candidate) -> {
+			BillOfMaterials actual = toBom(candidate);
+			return groupId.equals(actual.getGroupId()) && artifactId.equals(actual.getArtifactId());
+		});
+		return this;
+	}
+
 	/**
 	 * Assert {@code pom.xml} defines the specified number of repositories.
 	 * @param size the number of repositories

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2020 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.
@@ -234,6 +234,22 @@ class MavenBuildAssertTests {
 				() -> assertThat(forSampleMavenBuild()).hasBom("com.example.acme", "library-bom", "${wrong.version}"));
 	}
 
+	@Test
+	void doesNotHaveBomArtifactId() {
+		assertThat(forSampleMavenBuild()).doesNotHaveBom("com.example.acme", "wrong");
+	}
+
+	@Test
+	void doesNotHaveBomGroupId() {
+		assertThat(forSampleMavenBuild()).doesNotHaveBom("com.example.wrong", "library-bom");
+	}
+
+	@Test
+	void doesNotHaveBomWithMatchingBom() {
+		assertThatExceptionOfType(AssertionError.class)
+				.isThrownBy(() -> assertThat(forSampleMavenBuild()).doesNotHaveBom("com.example.acme", "library-bom"));
+	}
+
 	@Test
 	void hasRepositoriesSize() {
 		assertThat(forMavenBuild("sample-repositories-pom.xml")).hasRepositoriesSize(2);