Test uses local classpath

gradle-palantir-java-format/build.gradle

@@ -41,3 +41,20 @@ idea {
         sourceDirs += sourceSets.main.groovy.srcDirs
     }
 }
+
+configurations {
+    impl
+}
+
+dependencies {
+    impl project(':palantir-java-format')
+}
+
+task writeImplClasspath {
+    dependsOn configurations.impl
+    doLast {
+        file("$buildDir/impl.classpath").text = configurations.impl.asPath
+    }
+}
+
+test.dependsOn tasks.writeImplClasspath

gradle-palantir-java-format/src/main/groovy/com/palantir/javaformat/gradle/PalantirJavaFormatIdeaPlugin.java

@@ -33,19 +33,19 @@
 public final class PalantirJavaFormatIdeaPlugin implements Plugin<Project> {
 
     @Override
-    public void apply(Project project) {
+    public void apply(Project rootProject) {
         Preconditions.checkState(
-                project == project.getRootProject(),
+                rootProject == rootProject.getRootProject(),
                 "May only apply com.palantir.java-format-idea to the root project");
 
-        project.getPlugins().apply(PalantirJavaFormatProviderPlugin.class);
+        rootProject.getPlugins().apply(PalantirJavaFormatProviderPlugin.class);
 
-        project.getPluginManager().withPlugin("idea", ideaPlugin -> {
+        rootProject.getPluginManager().withPlugin("idea", ideaPlugin -> {
             Configuration implConfiguration =
-                    project.getConfigurations().getByName(PalantirJavaFormatProviderPlugin.CONFIGURATION_NAME);
+                    rootProject.getConfigurations().getByName(PalantirJavaFormatProviderPlugin.CONFIGURATION_NAME);
 
-            configureLegacyIdea(project, implConfiguration);
-            configureIntelliJImport(project, implConfiguration);
+            configureLegacyIdea(rootProject, implConfiguration);
+            configureIntelliJImport(rootProject, implConfiguration);
         });
     }
 

gradle-palantir-java-format/src/test/groovy/com/palantir/javaformat/gradle/PalantirJavaFormatPluginTest.groovy

@@ -20,12 +20,19 @@ import nebula.test.IntegrationTestKitSpec
 
 class PalantirJavaFormatPluginTest extends IntegrationTestKitSpec {
 
+    /** ./gradlew writeImplClasspath generates this file. */
+    private static final CLASSPATH_FILE = new File("build/impl.classpath").absolutePath
+
     void setup() {
         buildFile << """
             plugins {
                 id 'java'
                 id 'com.palantir.java-format'
             }
+
+            dependencies {
+                palantirJavaFormat files(file("${CLASSPATH_FILE}").text.split(':'))
+            }
             apply plugin: 'idea'
         """.stripIndent()
     }