Avoid stale inputs by using sync rather than copy

Closes gh-30829

Author: wilkinsona

buildSrc/src/main/java/org/springframework/boot/build/mavenplugin/MavenPluginPlugin.java

@@ -69,7 +69,6 @@
 import org.gradle.api.publish.maven.MavenPublication;
 import org.gradle.api.publish.maven.plugins.MavenPublishPlugin;
 import org.gradle.api.tasks.Classpath;
-import org.gradle.api.tasks.Copy;
 import org.gradle.api.tasks.InputFiles;
 import org.gradle.api.tasks.JavaExec;
 import org.gradle.api.tasks.OutputDirectory;
@@ -78,6 +77,7 @@
 import org.gradle.api.tasks.PathSensitivity;
 import org.gradle.api.tasks.SourceSet;
 import org.gradle.api.tasks.SourceSetContainer;
+import org.gradle.api.tasks.Sync;
 import org.gradle.api.tasks.TaskAction;
 import org.gradle.api.tasks.TaskExecutionException;
 import org.gradle.api.tasks.bundling.Jar;
@@ -154,7 +154,7 @@ private void addPopulateIntTestMavenRepositoryTask(Project project) {
 				.set(new File(project.getBuildDir(), "runtime-classpath-repository"));
 		project.getDependencies()
 				.components((components) -> components.all(MavenRepositoryComponentMetadataRule.class));
-		Copy task = project.getTasks().create("populateIntTestMavenRepository", Copy.class);
+		Sync task = project.getTasks().create("populateIntTestMavenRepository", Sync.class);
 		task.setDestinationDir(new File(project.getBuildDir(), "int-test-maven-repository"));
 		task.with(copyIntTestMavenRepositoryFiles(project, runtimeClasspathMavenRepository));
 		task.dependsOn(project.getTasks().getByName(MavenRepositoryPlugin.PUBLISH_TO_PROJECT_REPOSITORY_TASK_NAME));
@@ -181,7 +181,7 @@ private void addDocumentPluginGoalsTask(Project project, MavenExec generatePlugi
 	private MavenExec addGenerateHelpMojoTask(Project project, Jar jarTask) {
 		File helpMojoDir = new File(project.getBuildDir(), "help-mojo");
 		MavenExec task = createGenerateHelpMojoTask(project, helpMojoDir);
-		task.dependsOn(createCopyHelpMojoInputsTask(project, helpMojoDir));
+		task.dependsOn(createSyncHelpMojoInputsTask(project, helpMojoDir));
 		includeHelpMojoInJar(jarTask, task);
 		return task;
 	}
@@ -194,8 +194,8 @@ private MavenExec createGenerateHelpMojoTask(Project project, File helpMojoDir)
 		return task;
 	}
 
-	private Copy createCopyHelpMojoInputsTask(Project project, File helpMojoDir) {
-		Copy task = project.getTasks().create("copyHelpMojoInputs", Copy.class);
+	private Sync createSyncHelpMojoInputsTask(Project project, File helpMojoDir) {
+		Sync task = project.getTasks().create("syncHelpMojoInputs", Sync.class);
 		task.setDestinationDir(helpMojoDir);
 		File pomFile = new File(project.getProjectDir(), "src/maven/resources/pom.xml");
 		task.from(pomFile, (copy) -> replaceVersionPlaceholder(copy, project));
@@ -212,11 +212,11 @@ private MavenExec addGeneratePluginDescriptorTask(Project project, Jar jarTask,
 		File generatedHelpMojoDir = new File(project.getBuildDir(), "generated/sources/helpMojo");
 		SourceSet mainSourceSet = getMainSourceSet(project);
 		project.getTasks().withType(Javadoc.class, this::setJavadocOptions);
-		FormatHelpMojoSourceTask copyFormattedHelpMojoSourceTask = createCopyFormattedHelpMojoSourceTask(project,
+		FormatHelpMojoSource copyFormattedHelpMojoSourceTask = createFormatHelpMojoSourceTask(project,
 				generateHelpMojoTask, generatedHelpMojoDir);
 		project.getTasks().getByName(mainSourceSet.getCompileJavaTaskName()).dependsOn(copyFormattedHelpMojoSourceTask);
 		mainSourceSet.java((javaSources) -> javaSources.srcDir(copyFormattedHelpMojoSourceTask));
-		Copy pluginDescriptorInputs = createCopyPluginDescriptorInputs(project, pluginDescriptorDir, mainSourceSet);
+		Sync pluginDescriptorInputs = createSyncPluginDescriptorInputs(project, pluginDescriptorDir, mainSourceSet);
 		pluginDescriptorInputs.dependsOn(mainSourceSet.getClassesTaskName());
 		MavenExec task = createGeneratePluginDescriptorTask(project, pluginDescriptorDir);
 		task.dependsOn(pluginDescriptorInputs);
@@ -234,17 +234,17 @@ private void setJavadocOptions(Javadoc javadoc) {
 		options.addMultilineStringsOption("tag").setValue(Arrays.asList("goal:X", "requiresProject:X", "threadSafe:X"));
 	}
 
-	private FormatHelpMojoSourceTask createCopyFormattedHelpMojoSourceTask(Project project,
-			MavenExec generateHelpMojoTask, File generatedHelpMojoDir) {
-		FormatHelpMojoSourceTask copyFormattedHelpMojoSourceTask = project.getTasks()
-				.create("copyFormattedHelpMojoSource", FormatHelpMojoSourceTask.class);
-		copyFormattedHelpMojoSourceTask.setGenerator(generateHelpMojoTask);
-		copyFormattedHelpMojoSourceTask.setOutputDir(generatedHelpMojoDir);
-		return copyFormattedHelpMojoSourceTask;
+	private FormatHelpMojoSource createFormatHelpMojoSourceTask(Project project, MavenExec generateHelpMojoTask,
+			File generatedHelpMojoDir) {
+		FormatHelpMojoSource formatHelpMojoSource = project.getTasks().create("formatHelpMojoSource",
+				FormatHelpMojoSource.class);
+		formatHelpMojoSource.setGenerator(generateHelpMojoTask);
+		formatHelpMojoSource.setOutputDir(generatedHelpMojoDir);
+		return formatHelpMojoSource;
 	}
 
-	private Copy createCopyPluginDescriptorInputs(Project project, File destination, SourceSet sourceSet) {
-		Copy pluginDescriptorInputs = project.getTasks().create("copyPluginDescriptorInputs", Copy.class);
+	private Sync createSyncPluginDescriptorInputs(Project project, File destination, SourceSet sourceSet) {
+		Sync pluginDescriptorInputs = project.getTasks().create("copyPluginDescriptorInputs", Sync.class);
 		pluginDescriptorInputs.setDestinationDir(destination);
 		File pomFile = new File(project.getProjectDir(), "src/maven/resources/pom.xml");
 		pluginDescriptorInputs.from(pomFile, (copy) -> replaceVersionPlaceholder(copy, project));
@@ -291,7 +291,7 @@ private void addExtractVersionPropertiesTask(Project project) {
 				.map((dir) -> dir.file("extracted-versions.properties")));
 	}
 
-	public static class FormatHelpMojoSourceTask extends DefaultTask {
+	public static class FormatHelpMojoSource extends DefaultTask {
 
 		private Task generator;