Gradle IDEA integration.

IDEA running using gradle

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

@@ -39,6 +39,7 @@
 import com.diffplug.spotless.java.CleanthatJavaStep;
 import com.diffplug.spotless.java.FormatAnnotationsStep;
 import com.diffplug.spotless.java.GoogleJavaFormatStep;
+import com.diffplug.spotless.java.IdeaStep;
 import com.diffplug.spotless.java.ImportOrderStep;
 import com.diffplug.spotless.java.PalantirJavaFormatStep;
 import com.diffplug.spotless.java.RemoveUnusedImportsStep;
@@ -313,6 +314,37 @@ public EclipseConfig withP2Mirrors(Map<String, String> mirrors) {
 
 	}
 
+	public IdeaConfig idea() {
+		return new IdeaConfig();
+	}
+
+	public class IdeaConfig {
+		String binaryPath;
+		boolean withDefaults = false;
+
+		IdeaConfig() {
+			addStep(createStep());
+		}
+
+		private FormatterStep createStep() {
+			return IdeaStep.create(withDefaults, binaryPath);
+		}
+
+		public IdeaConfig binaryPath(String binaryPath) {
+			Objects.requireNonNull(binaryPath);
+			this.binaryPath = binaryPath;
+			replaceStep(createStep());
+			return this;
+		}
+
+		public IdeaConfig withDefaults(Boolean withDefaults) {
+			Objects.requireNonNull(withDefaults);
+			this.withDefaults = withDefaults;
+			replaceStep(createStep());
+			return this;
+		}
+	}
+
 	/** Removes newlines between type annotations and types. */
 	public FormatAnnotationsConfig formatAnnotations() {
 		return new FormatAnnotationsConfig();
@@ -400,7 +432,7 @@ public CleanthatJavaConfig clearMutators() {
 		}
 
 		// An id of a mutator (see IMutator.getIds()) or
-		// tThe fully qualified name of a class implementing eu.solven.cleanthat.engine.java.refactorer.meta.IMutator
+		// The fully qualified name of a class implementing eu.solven.cleanthat.engine.java.refactorer.meta.IMutator
 		public CleanthatJavaConfig addMutator(String mutator) {
 			this.mutators.add(mutator);
 			replaceStep(createStep());

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

@@ -0,0 +1,41 @@
+/*
+ * Copyright 2020-2024 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.io.IOException;
+
+import org.junit.jupiter.api.Test;
+
+
+class JavaIdeaTest extends GradleIntegrationHarness {
+	@Test
+	void idea() throws IOException {
+		setFile("build.gradle").toLines(
+				"plugins {",
+				"  id 'com.diffplug.spotless'",
+				"}",
+				"spotless {",
+				"  java {",
+				"    target file('test.java')",
+				"    idea().binaryPath('idea').withDefaults(true)",
+				"  }",
+				"}");
+
+		setFile("test.java").toResource("java/idea/full.dirty.java");
+		gradleRunner().withArguments("spotlessApply").build();
+		assertFile("test.java").notSameAsResource("java/idea/full.dirty.java");
+	}
+}

testlib/src/main/java/com/diffplug/spotless/ResourceHarness.java

@@ -151,10 +151,18 @@ public void hasContent(String expected) {
 			hasContent(expected, StandardCharsets.UTF_8);
 		}
 
+		public void hasDifferentContent(String expected) {
+			hasDifferentContent(expected, StandardCharsets.UTF_8);
+		}
+
 		public void hasContent(String expected, Charset charset) {
 			assertThat(file).usingCharset(charset).hasContent(expected);
 		}
 
+		public void hasDifferentContent(String expected, Charset charset) {
+			assertThat(file).usingCharset(charset).isNotEqualTo(expected);
+		}
+
 		public void hasLines(String... lines) {
 			hasContent(String.join("\n", Arrays.asList(lines)));
 		}
@@ -163,6 +171,10 @@ public void sameAsResource(String resource) throws IOException {
 			hasContent(getTestResource(resource));
 		}
 
+		public void notSameAsResource(String resource) throws IOException {
+			hasDifferentContent(getTestResource(resource));
+		}
+
 		public void matches(Consumer<AbstractCharSequenceAssert<?, String>> conditions) throws IOException {
 			String content = new String(Files.readAllBytes(file.toPath()), StandardCharsets.UTF_8);
 			conditions.accept(assertThat(content));