Maven IDE hook (#1782)

plugin-maven/CHANGES.md

@@ -4,6 +4,8 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 
 ## [Unreleased]
 ### Added
+* Add `-DspotlessIdeHook` that provides the ability to apply Spotless exclusively to a specified file. It accepts the absolute path of the file. ([#1782](https://github.com/diffplug/spotless/pull/1782))
+  * BETA, subject to change until we have proven compatibility with some IDE plugins.
 * Added support for `google-java-format`'s `skip-javadoc-formatting` option ([#1793](https://github.com/diffplug/spotless/pull/1793))
 * Added support for biome. The Rome project [was renamed to Biome](https://biomejs.dev/blog/annoucing-biome/).
   The configuration is still the same, but you should switch to the new `<biome>` tag and adjust

plugin-maven/build.gradle

@@ -39,6 +39,7 @@ dependencies {
 	compileOnly "org.eclipse.aether:aether-api:${VER_ECLIPSE_AETHER}"
 
 	implementation "com.diffplug.durian:durian-core:${VER_DURIAN}"
+	implementation "com.diffplug.durian:durian-io:${VER_DURIAN}"
 	implementation "com.diffplug.durian:durian-collect:${VER_DURIAN}"
 	implementation("org.codehaus.plexus:plexus-resources:${VER_PLEXUS_RESOURCES}")
 	implementation "org.eclipse.jgit:org.eclipse.jgit:${VER_JGIT}"

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

@@ -0,0 +1,83 @@
+/*
+ * Copyright 2016-2023 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.spotless.maven;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+
+import com.diffplug.common.base.Errors;
+import com.diffplug.common.io.ByteStreams;
+import com.diffplug.spotless.Formatter;
+import com.diffplug.spotless.PaddedCell;
+
+class IdeHook {
+
+	private static void dumpIsClean() {
+		System.err.println("IS CLEAN");
+	}
+
+	//No need to check ratchet (using isClean()) as it is performed in Gradle's IDE hook, since we have already gathered the available git files from ratchet.
+	static void performHook(Iterable<File> projectFiles, Formatter formatter, String path, boolean spotlessIdeHookUseStdIn, boolean spotlessIdeHookUseStdOut) {
+		File file = new File(path);
+		if (!file.isAbsolute()) {
+			System.err.println("Argument passed to spotlessIdeHook must be an absolute path");
+			return;
+		}
+
+		if (!projectContainsFile(projectFiles, file)) {
+			return;
+		}
+
+		try {
+			byte[] bytes;
+			if (spotlessIdeHookUseStdIn) {
+				bytes = ByteStreams.toByteArray(System.in);
+			} else {
+				bytes = Files.readAllBytes(file.toPath());
+			}
+			PaddedCell.DirtyState dirty = PaddedCell.calculateDirtyState(formatter, file, bytes);
+			if (dirty.isClean()) {
+				dumpIsClean();
+			} else if (dirty.didNotConverge()) {
+				System.err.println("DID NOT CONVERGE");
+				System.err.println("See details https://github.com/diffplug/spotless/blob/main/PADDEDCELL.md");
+			} else {
+				System.err.println("IS DIRTY");
+				if (spotlessIdeHookUseStdOut) {
+					dirty.writeCanonicalTo(System.out);
+				} else {
+					dirty.writeCanonicalTo(file);
+				}
+			}
+		} catch (IOException e) {
+			e.printStackTrace(System.err);
+			throw Errors.asRuntime(e);
+		} finally {
+			System.err.close();
+			System.out.close();
+		}
+	}
+
+	private static boolean projectContainsFile(Iterable<File> projectFiles, File file) {
+		for (File projectFile : projectFiles) {
+			if (projectFile.equals(file)) {
+				return true;
+			}
+		}
+		return false;
+	}
+}

plugin-maven/src/main/java/com/diffplug/spotless/maven/SpotlessApplyMojo.java

@@ -20,6 +20,7 @@
 
 import org.apache.maven.plugin.MojoExecutionException;
 import org.apache.maven.plugins.annotations.Mojo;
+import org.apache.maven.plugins.annotations.Parameter;
 
 import com.diffplug.spotless.Formatter;
 import com.diffplug.spotless.PaddedCell;
@@ -31,8 +32,22 @@
 @Mojo(name = AbstractSpotlessMojo.GOAL_APPLY, threadSafe = true)
 public class SpotlessApplyMojo extends AbstractSpotlessMojo {
 
+	@Parameter(property = "spotlessIdeHook")
+	private String spotlessIdeHook;
+
+	@Parameter(property = "spotlessIdeHookUseStdIn")
+	private boolean spotlessIdeHookUseStdIn;
+
+	@Parameter(property = "spotlessIdeHookUseStdOut")
+	private boolean spotlessIdeHookUseStdOut;
+
 	@Override
 	protected void process(Iterable<File> files, Formatter formatter, UpToDateChecker upToDateChecker) throws MojoExecutionException {
+		if (isIdeHook()) {
+			IdeHook.performHook(files, formatter, spotlessIdeHook, spotlessIdeHookUseStdIn, spotlessIdeHookUseStdOut);
+			return;
+		}
+
 		ImpactedFilesTracker counter = new ImpactedFilesTracker();
 
 		for (File file : files) {
@@ -69,4 +84,8 @@ protected void process(Iterable<File> files, Formatter formatter, UpToDateChecke
 			getLog().debug(String.format("Spotless.%s has no target files. Examine your `<includes>`: https://github.com/diffplug/spotless/tree/main/plugin-maven#quickstart", formatter.getName()));
 		}
 	}
+
+	private boolean isIdeHook() {
+		return !(spotlessIdeHook == null || spotlessIdeHook.isEmpty());
+	}
 }

plugin-maven/src/test/java/com/diffplug/spotless/maven/IdeHookTest.java

@@ -0,0 +1,85 @@
+/*
+ * Copyright 2016-2023 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.spotless.maven;
+
+import java.io.File;
+import java.io.IOException;
+
+import org.assertj.core.api.Assertions;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import com.diffplug.spotless.ProcessRunner;
+
+class IdeHookTest extends MavenIntegrationHarness {
+	private String output, error;
+	private File dirty, clean, diverge, outofbounds;
+
+	@BeforeEach
+	void before() throws IOException {
+		writePomWithFormatSteps("<includes>\n" +
+				"                                <include>DIRTY.md</include>\n" +
+				"                                <include>CLEAN.md</include>\n" +
+				"                            </includes>\n" +
+				"                            <replace>\n" +
+				"                                <name>Greetings to Mars</name>\n" +
+				"                                <search>World</search>\n" +
+				"                                <replacement>Mars</replacement>\n" +
+				"                            </replace>");
+
+		dirty = setFile("DIRTY.md").toContent("World");
+		clean = setFile("CLEAN.md").toContent("Mars");
+		outofbounds = setFile("OUTOFBOUNDS.md").toContent("Mars");
+		;
+	}
+
+	private void runWith(String... arguments) throws IOException, InterruptedException {
+		ProcessRunner.Result result = mavenRunner()
+				.withArguments(arguments)
+				.runNoError();
+
+		this.output = result.stdOutUtf8();
+		this.error = result.stdErrUtf8();
+	}
+
+	@Test
+	void dirty() throws IOException, InterruptedException {
+		runWith("spotless:apply", "--quiet", "-DspotlessIdeHook=\"" + dirty.getAbsolutePath() + "\"", "-DspotlessIdeHookUseStdOut=true");
+		Assertions.assertThat(output).isEqualTo("Mars");
+		Assertions.assertThat(error).startsWith("IS DIRTY");
+	}
+
+	@Test
+	void clean() throws IOException, InterruptedException {
+		runWith("spotless:apply", "--quiet", "-DspotlessIdeHook=" + clean.getAbsolutePath(), "-DspotlessIdeHookUseStdOut=true");
+		Assertions.assertThat(output).isEmpty();
+		Assertions.assertThat(error).startsWith("IS CLEAN");
+	}
+
+	@Test
+	void outofbounds() throws IOException, InterruptedException {
+		runWith("spotless:apply", "--quiet", "-DspotlessIdeHook=" + outofbounds.getAbsolutePath(), "-DspotlessIdeHookUseStdOut=true");
+		Assertions.assertThat(output).isEmpty();
+		Assertions.assertThat(error).isEmpty();
+	}
+
+	@Test
+	void notAbsolute() throws IOException, InterruptedException {
+		runWith("spotless:apply", "--quiet", "-DspotlessIdeHook=\"pom.xml\"", "-DspotlessIdeHookUseStdOut=true");
+		Assertions.assertThat(output).isEmpty();
+		Assertions.assertThat(error).contains("Argument passed to spotlessIdeHook must be an absolute path");
+	}
+}