Make SpotlessDiagnoseTask compatible with the configuration cache

plugin-gradle/CHANGES.md

@@ -3,6 +3,8 @@
 We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (starting after version `3.27.0`).
 
 ## [Unreleased]
+### Fixed
+* Make `SpotlessDiagnoseTask` compatible with the configuration cache` ([#2504](https://github.com/diffplug/spotless/pull/2504))
 
 ## [7.0.4] - 2025-05-27
 ### Fixed

plugin-gradle/src/main/java/com/diffplug/gradle/spotless/FormatterSpec.java

@@ -0,0 +1,68 @@
+/*
+ * Copyright 2025 DiffPlug
+ *
+ * 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
+ *
+ *     http://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 com.diffplug.gradle.spotless;
+
+import java.nio.charset.Charset;
+
+import org.gradle.api.model.ObjectFactory;
+import org.gradle.api.provider.Property;
+import org.gradle.api.tasks.Input;
+import org.gradle.api.tasks.Internal;
+
+import com.diffplug.spotless.ConfigurationCacheHackList;
+import com.diffplug.spotless.Formatter;
+import com.diffplug.spotless.LineEnding;
+
+final class FormatterSpec {
+
+	private final Property<String> encoding;
+
+	@Input
+	Property<String> getEncoding() {
+		return encoding;
+	}
+
+	private final Property<LineEnding.Policy> lineEndingsPolicy;
+
+	@Input
+	Property<LineEnding.Policy> getLineEndingsPolicy() {
+		return lineEndingsPolicy;
+	}
+
+	private final ConfigurationCacheHackList stepsInternalRoundtrip = ConfigurationCacheHackList.forRoundtrip();
+
+	@Internal
+	public ConfigurationCacheHackList getStepsInternalRoundtrip() {
+		return stepsInternalRoundtrip;
+	}
+
+	FormatterSpec(ObjectFactory objects) {
+		encoding = objects.property(String.class);
+		lineEndingsPolicy = objects.property(LineEnding.Policy.class);
+
+		// set by SpotlessExtension, but possibly overridden by FormatExtension
+		getEncoding().convention("UTF-8");
+	}
+
+	Formatter buildFormatter() {
+		return Formatter.builder()
+				.lineEndingsPolicy(getLineEndingsPolicy().get())
+				.encoding(Charset.forName(getEncoding().get()))
+				.steps(stepsInternalRoundtrip.getSteps())
+				.build();
+	}
+
+}

plugin-gradle/src/main/java/com/diffplug/gradle/spotless/IdeHook.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2024 DiffPlug
+ * Copyright 2016-2025 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -63,7 +63,7 @@ static void performHook(SpotlessTaskImpl spotlessTask, IdeHook.State state) {
 		}
 		if (spotlessTask.getTarget().contains(file)) {
 			GitRatchetGradle ratchet = spotlessTask.getRatchet();
-			try (Formatter formatter = spotlessTask.buildFormatter()) {
+			try (Formatter formatter = spotlessTask.getFormatterSpec().buildFormatter()) {
 				if (ratchet != null) {
 					if (ratchet.isClean(spotlessTask.getProjectDir().get().getAsFile(), spotlessTask.getRootTreeSha(), file)) {
 						dumpIsClean();

plugin-gradle/src/main/java/com/diffplug/gradle/spotless/SpotlessDiagnoseTask.java

@@ -22,8 +22,17 @@
 import java.nio.file.Paths;
 import java.util.Locale;
 
+import javax.inject.Inject;
+
 import org.gradle.api.DefaultTask;
-import org.gradle.api.tasks.Internal;
+import org.gradle.api.file.ConfigurableFileCollection;
+import org.gradle.api.file.FileSystemOperations;
+import org.gradle.api.file.ProjectLayout;
+import org.gradle.api.provider.Property;
+import org.gradle.api.tasks.Input;
+import org.gradle.api.tasks.InputFiles;
+import org.gradle.api.tasks.PathSensitive;
+import org.gradle.api.tasks.PathSensitivity;
 import org.gradle.api.tasks.TaskAction;
 import org.gradle.api.tasks.UntrackedTask;
 
@@ -33,23 +42,39 @@
 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 
 @UntrackedTask(because = "undeclared inputs/outputs")
-public class SpotlessDiagnoseTask extends DefaultTask {
-	SpotlessTask source;
+public abstract class SpotlessDiagnoseTask extends DefaultTask {
+
+	@Inject
+	protected abstract ProjectLayout getProjectLayout();
+
+	@Inject
+	protected abstract FileSystemOperations getFileSystemOperations();
+
+	@Input
+	protected abstract Property<String> getFormatName();
+
+	@Input
+	protected abstract Property<FormatterSpec> getFormatter();
+
+	@InputFiles
+	@PathSensitive(PathSensitivity.RELATIVE)
+	protected abstract ConfigurableFileCollection getTarget();
 
-	@Internal
-	public SpotlessTask getSource() {
-		return source;
+	void init(SpotlessTask source) {
+		getFormatName().convention(source.formatName());
+		getFormatter().convention(source.getFormatterSpec());
+		getTarget().setFrom(source.getTarget());
 	}
 
 	@TaskAction
 	@SuppressFBWarnings("NP_NULL_ON_SOME_PATH_FROM_RETURN_VALUE")
 	public void performAction() throws IOException {
-		Path srcRoot = getProject().getProjectDir().toPath();
-		Path diagnoseRoot = getProject().getLayout().getBuildDirectory().getAsFile().get()
-				.toPath().resolve("spotless-diagnose-" + source.formatName());
-		getProject().delete(diagnoseRoot.toFile());
-		try (Formatter formatter = source.buildFormatter()) {
-			for (File file : source.target) {
+		Path srcRoot = getProjectLayout().getProjectDirectory().getAsFile().toPath();
+		Path diagnoseRoot = getProjectLayout().getBuildDirectory().getAsFile().get()
+				.toPath().resolve("spotless-diagnose-" + getFormatName().get());
+		getFileSystemOperations().delete(spec -> spec.delete(diagnoseRoot));
+		try (Formatter formatter = getFormatter().get().buildFormatter()) {
+			for (File file : getTarget()) {
 				getLogger().debug("Running padded cell check on " + file);
 				PaddedCell padded = PaddedCell.check(formatter, file);
 				if (!padded.misbehaved()) {

plugin-gradle/src/main/java/com/diffplug/gradle/spotless/SpotlessExtensionImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2024 DiffPlug
+ * Copyright 2016-2025 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -96,7 +96,9 @@ protected void createFormatTasks(String name, FormatExtension formatExtension) {
 
 		// create the diagnose task
 		TaskProvider<SpotlessDiagnoseTask> diagnoseTask = tasks.register(taskName + DIAGNOSE, SpotlessDiagnoseTask.class, task -> {
-			task.source = spotlessTask.get();
+			SpotlessTaskImpl source = spotlessTask.get();
+			task.init(source);
+
 			task.setGroup(TASK_GROUP);
 			task.mustRunAfter(BasePlugin.CLEAN_TASK_NAME);
 		});

plugin-gradle/src/main/java/com/diffplug/gradle/spotless/SpotlessTask.java

@@ -16,29 +16,30 @@
 package com.diffplug.gradle.spotless;
 
 import java.io.File;
-import java.nio.charset.Charset;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Locale;
 import java.util.Objects;
 
 import org.eclipse.jgit.lib.ObjectId;
 import org.gradle.api.DefaultTask;
+import org.gradle.api.file.ConfigurableFileCollection;
 import org.gradle.api.file.DirectoryProperty;
 import org.gradle.api.file.FileCollection;
 import org.gradle.api.provider.Property;
 import org.gradle.api.provider.Provider;
 import org.gradle.api.tasks.Input;
 import org.gradle.api.tasks.InputFiles;
 import org.gradle.api.tasks.Internal;
+import org.gradle.api.tasks.Nested;
 import org.gradle.api.tasks.OutputDirectory;
 import org.gradle.api.tasks.PathSensitive;
 import org.gradle.api.tasks.PathSensitivity;
+import org.gradle.api.tasks.SkipWhenEmpty;
 import org.gradle.work.DisableCachingByDefault;
 import org.gradle.work.Incremental;
 
 import com.diffplug.spotless.ConfigurationCacheHackList;
-import com.diffplug.spotless.Formatter;
 import com.diffplug.spotless.FormatterStep;
 import com.diffplug.spotless.LineEnding;
 import com.diffplug.spotless.LintSuppression;
@@ -49,27 +50,29 @@ public abstract class SpotlessTask extends DefaultTask {
 	@Internal
 	abstract Property<SpotlessTaskService> getTaskService();
 
-	// set by SpotlessExtension, but possibly overridden by FormatExtension
-	protected String encoding = "UTF-8";
+	private final FormatterSpec formatterSpec = new FormatterSpec(getProject().getObjects());
 
-	@Input
+	@Nested
+	protected FormatterSpec getFormatterSpec() {
+		return formatterSpec;
+	}
+
+	@Internal
 	public String getEncoding() {
-		return encoding;
+		return getFormatterSpec().getEncoding().get();
 	}
 
 	public void setEncoding(String encoding) {
-		this.encoding = Objects.requireNonNull(encoding);
+		getFormatterSpec().getEncoding().set(Objects.requireNonNull(encoding));
 	}
 
-	protected Provider<LineEnding.Policy> lineEndingsPolicy = null;
-
-	@Input
+	@Internal
 	public Provider<LineEnding.Policy> getLineEndingsPolicy() {
-		return lineEndingsPolicy;
+		return getFormatterSpec().getLineEndingsPolicy();
 	}
 
 	public void setLineEndingsPolicy(Provider<LineEnding.Policy> lineEndingsPolicy) {
-		this.lineEndingsPolicy = lineEndingsPolicy;
+		getFormatterSpec().getLineEndingsPolicy().set(lineEndingsPolicy);
 	}
 
 	/**
@@ -135,21 +138,19 @@ public List<LintSuppression> getLintSuppressions() {
 		return lintSuppressions;
 	}
 
-	protected FileCollection target;
+	@Internal
+	protected abstract ConfigurableFileCollection getTargetInternal();
 
 	@PathSensitive(PathSensitivity.RELATIVE)
 	@Incremental
 	@InputFiles
+	@SkipWhenEmpty
 	public FileCollection getTarget() {
-		return target;
+		return getTargetInternal();
 	}
 
 	public void setTarget(Iterable<File> target) {
-		if (target instanceof FileCollection) {
-			this.target = (FileCollection) target;
-		} else {
-			this.target = getProject().files(target);
-		}
+		getTargetInternal().setFrom(target);
 	}
 
 	protected File cleanDirectory = new File(getProject().getLayout().getBuildDirectory().getAsFile().get(),
@@ -168,24 +169,18 @@ public File getLintsDirectory() {
 		return lintsDirectory;
 	}
 
-	private final ConfigurationCacheHackList stepsInternalRoundtrip = ConfigurationCacheHackList.forRoundtrip();
 	private final ConfigurationCacheHackList stepsInternalEquality = ConfigurationCacheHackList.forEquality();
 
-	@Internal
-	public ConfigurationCacheHackList getStepsInternalRoundtrip() {
-		return stepsInternalRoundtrip;
-	}
-
 	@Input
 	public ConfigurationCacheHackList getStepsInternalEquality() {
 		return stepsInternalEquality;
 	}
 
 	public void setSteps(List<FormatterStep> steps) {
 		PluginGradlePreconditions.requireElementsNonNull(steps);
-		this.stepsInternalRoundtrip.clear();
+		this.formatterSpec.getStepsInternalRoundtrip().clear();
 		this.stepsInternalEquality.clear();
-		this.stepsInternalRoundtrip.addAll(steps);
+		this.formatterSpec.getStepsInternalRoundtrip().addAll(steps);
 		this.stepsInternalEquality.addAll(steps);
 	}
 
@@ -198,12 +193,4 @@ String formatName() {
 			return name;
 		}
 	}
-
-	Formatter buildFormatter() {
-		return Formatter.builder()
-				.lineEndingsPolicy(getLineEndingsPolicy().get())
-				.encoding(Charset.forName(encoding))
-				.steps(stepsInternalRoundtrip.getSteps())
-				.build();
-	}
 }

plugin-gradle/src/main/java/com/diffplug/gradle/spotless/SpotlessTaskImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2024 DiffPlug
+ * Copyright 2016-2025 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -84,7 +84,7 @@ public void performAction(InputChanges inputs) throws Exception {
 
 		SpotlessTaskService taskService = getTaskService().get();
 		taskService.registerSourceAlreadyRan(this);
-		if (target == null) {
+		if (getTargetInternal().getFrom().isEmpty()) {
 			throw new GradleException("You must specify 'Iterable<File> target'");
 		}
 
@@ -96,9 +96,9 @@ public void performAction(InputChanges inputs) throws Exception {
 			Files.createDirectories(lintsDirectory.toPath());
 		}
 
-		try (Formatter formatter = buildFormatter()) {
+		try (Formatter formatter = getFormatterSpec().buildFormatter()) {
 			GitRatchetGradle ratchet = getRatchet();
-			for (FileChange fileChange : inputs.getFileChanges(target)) {
+			for (FileChange fileChange : inputs.getFileChanges(getTarget())) {
 				File input = fileChange.getFile();
 				File projectDir = getProjectDir().get().getAsFile();
 				String relativePath = FormatExtension.relativize(projectDir, input);

plugin-gradle/src/test/java/com/diffplug/gradle/spotless/ConfigurationCacheTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2020-2024 DiffPlug
+ * Copyright 2020-2025 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -84,10 +84,12 @@ public void multipleRuns() throws IOException {
 		gradleRunner().withArguments("spotlessApply", "--stacktrace").build();
 		gradleRunner().withArguments("spotlessApply").build();
 		gradleRunner().withArguments("spotlessApply").build();
+		gradleRunner().withArguments("spotlessDiagnose").build();
 
 		setFile("test.java").toResource("java/googlejavaformat/JavaCodeUnformatted.test");
 		gradleRunner().withArguments("spotlessCheck").buildAndFail();
 		gradleRunner().withArguments("spotlessApply").build();
+		gradleRunner().withArguments("spotlessDiagnose").build();
 		assertFile("test.java").sameAsResource("java/googlejavaformat/JavaCodeFormatted.test");
 	}
 }

plugin-gradle/src/test/java/com/diffplug/gradle/spotless/PaddedCellTaskTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2024 DiffPlug
+ * Copyright 2016-2025 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -96,7 +96,7 @@ String checkFailureMsg() {
 
 		void diagnose() throws IOException {
 			SpotlessDiagnoseTask diagnose = project.getTasks().create("spotless" + SpotlessPlugin.capitalize(name) + "Diagnose", SpotlessDiagnoseTask.class);
-			diagnose.source = source;
+			diagnose.init(source);
 			diagnose.performAction();
 		}