Add fix parameter to checkClassUniqueness (#2781)

gradle-baseline-java/src/main/groovy/com/palantir/baseline/plugins/BaselineClassUniquenessPlugin.java

@@ -41,6 +41,8 @@ public final void apply(Project project) {
         TaskProvider<CheckClassUniquenessLockTask> checkClassUniqueness = project.getTasks()
                 .register("checkClassUniqueness", CheckClassUniquenessLockTask.class, task -> {
                     task.jarClassHasher.set(jarClassHasher);
+                    task.shouldFix.convention(
+                            project.getGradle().getStartParameter().isWriteDependencyLocks());
                     task.usesService(jarClassHasher);
                 });
         project.getPlugins().apply(LifecycleBasePlugin.class);

gradle-baseline-java/src/main/groovy/com/palantir/baseline/tasks/CheckClassUniquenessLockTask.java

@@ -45,14 +45,15 @@
 import org.gradle.api.tasks.Input;
 import org.gradle.api.tasks.OutputFile;
 import org.gradle.api.tasks.TaskAction;
+import org.gradle.api.tasks.options.Option;
 import org.gradle.util.GFileUtils;
 
 @CacheableTask
 public class CheckClassUniquenessLockTask extends DefaultTask {
 
     private static final String HEADER = "# Danger! Multiple jars contain identically named classes. This may "
             + "cause different behaviour depending on classpath ordering.\n"
-            + "# Run ./gradlew checkClassUniqueness --write-locks to update this file\n\n";
+            + "# Run ./gradlew checkClassUniqueness --fix to update this file\n\n";
 
     // not marking this as an Input, because we want to re-run if the *contents* of a configuration changes
     @SuppressWarnings("VisibilityModifier")
@@ -61,11 +62,15 @@ public class CheckClassUniquenessLockTask extends DefaultTask {
     @SuppressWarnings("VisibilityModifier")
     public final Property<JarClassHasher> jarClassHasher;
 
+    @SuppressWarnings("VisibilityModifier")
+    public final Property<Boolean> shouldFix;
+
     private final File lockFile;
 
     public CheckClassUniquenessLockTask() {
         this.configurations = getProject().getObjects().setProperty(Configuration.class);
         this.jarClassHasher = getProject().getObjects().property(JarClassHasher.class);
+        this.shouldFix = getProject().getObjects().property(Boolean.class);
         this.lockFile = getProject().file("baseline-class-uniqueness.lock");
         onlyIf(new Spec<Task>() {
             @Override
@@ -93,6 +98,11 @@ public final File getLockFile() {
         return lockFile;
     }
 
+    @Option(option = "fix", description = "Whether to apply the suggested fix to baseline-class-uniqueness.lock")
+    public final void setShouldFix(boolean shouldFix) {
+        this.shouldFix.set(shouldFix);
+    }
+
     @TaskAction
     public final void doIt() {
         ImmutableSortedMap<String, Optional<String>> resultsByConfiguration = configurations.get().stream()
@@ -153,7 +163,7 @@ private String clashingJarHeader(Set<ModuleVersionIdentifier> clashingJars) {
     }
 
     private void ensureLockfileContains(String expected) {
-        if (getProject().getGradle().getStartParameter().isWriteDependencyLocks()) {
+        if (shouldFix.get()) {
             GFileUtils.writeFile(expected, lockFile);
             getLogger()
                     .lifecycle("Updated {}", getProject().getRootDir().toPath().relativize(lockFile.toPath()));
@@ -163,9 +173,9 @@ private void ensureLockfileContains(String expected) {
         if (!lockFile.exists()) {
             throw new ExceptionWithSuggestion(
                     "baseline-class-uniqueness detected multiple jars containing identically named classes."
-                            + " Please resolve these problems, or run `./gradlew checkClassUniqueness --write-locks`"
+                            + " Please resolve these problems, or run `./gradlew checkClassUniqueness --fix`"
                             + "to accept them:\n\n " + expected,
-                    "./gradlew checkClassUniqueness --write-locks");
+                    "./gradlew checkClassUniqueness --fix");
         }
 
         String onDisk = GFileUtils.readFile(lockFile);
@@ -177,7 +187,9 @@ private void ensureLockfileContains(String expected) {
                     String.join(
                             "\n",
                             String.format(
-                                    "%s is out of date, please run ` " + "to update this file. The diff is:", lockFile),
+                                    "%s is out of date, please run `./gradlew checkClassUniqueness --fix` to"
+                                            + " update this file. The diff is:",
+                                    lockFile),
                             "",
                             String.join(
                                     "\n",
@@ -190,13 +202,13 @@ private void ensureLockfileContains(String expected) {
                             "",
                             "Expected was:",
                             expected),
-                    "./gradlew checkClassUniqueness --write-locks");
+                    "./gradlew checkClassUniqueness --fix");
         }
     }
 
     private void ensureLockfileDoesNotExist() {
         if (lockFile.exists()) {
-            if (getProject().getGradle().getStartParameter().isWriteDependencyLocks()) {
+            if (shouldFix.get()) {
                 GFileUtils.deleteQuietly(lockFile);
                 getLogger()
                         .lifecycle(

gradle-baseline-java/src/test/groovy/com/palantir/baseline/BaselineClassUniquenessPluginIntegrationTest.groovy

@@ -37,6 +37,37 @@ class BaselineClassUniquenessPluginIntegrationTest extends AbstractPluginTest {
         }
     """.stripIndent()
 
+    def 'detect duplicates in two external jars, then --fix captures'() {
+        File lockfile = new File(projectDir, 'baseline-class-uniqueness.lock')
+
+        when:
+        buildFile << standardBuildFile
+        buildFile << """
+        dependencies {
+            api group: 'javax.el', name: 'javax.el-api', version: '3.0.0'
+            api group: 'javax.servlet.jsp', name: 'jsp-api', version: '2.1'
+        }
+        """.stripIndent()
+        BuildResult result = with('check', '-s').buildAndFail()
+
+        then:
+        result.getOutput().contains("baseline-class-uniqueness detected multiple jars containing identically named classes.")
+        result.getOutput().contains("[javax.el:javax.el-api, javax.servlet.jsp:jsp-api]")
+        result.getOutput().contains("javax.el.ArrayELResolver");
+        !lockfile.exists()
+
+        when:
+        with("checkClassUniqueness", "--fix").build()
+
+        then:
+        lockfile.exists()
+        File expected = new File("src/test/resources/com/palantir/baseline/baseline-class-uniqueness.expected.lock")
+        if (Boolean.getBoolean("recreate")) {
+            GFileUtils.writeFile(lockfile.text, expected)
+        }
+        lockfile.text == expected.text
+    }
+
     def 'detect duplicates in two external jars, then --write-locks captures'() {
         File lockfile = new File(projectDir, 'baseline-class-uniqueness.lock')
 
@@ -56,9 +87,11 @@ class BaselineClassUniquenessPluginIntegrationTest extends AbstractPluginTest {
         result.getOutput().contains("javax.el.ArrayELResolver");
         !lockfile.exists()
 
+        when:
         with("checkClassUniqueness", "--write-locks").build()
-        lockfile.exists()
 
+        then:
+        lockfile.exists()
         File expected = new File("src/test/resources/com/palantir/baseline/baseline-class-uniqueness.expected.lock")
         if (Boolean.getBoolean("recreate")) {
             GFileUtils.writeFile(lockfile.text, expected)

gradle-baseline-java/src/test/resources/com/palantir/baseline/baseline-class-uniqueness.expected.lock

@@ -1,5 +1,5 @@
 # Danger! Multiple jars contain identically named classes. This may cause different behaviour depending on classpath ordering.
-# Run ./gradlew checkClassUniqueness --write-locks to update this file
+# Run ./gradlew checkClassUniqueness --fix to update this file
 
 ## runtimeClasspath
 [javax.el:javax.el-api, javax.servlet.jsp:jsp-api]