chore: test cleanup behaviour

Author: simschla

app/src/main/java/com/diffplug/spotless/cli/core/SpotlessRunCleanup.java

@@ -19,7 +19,9 @@
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.Comparator;
+import java.util.concurrent.ConcurrentLinkedQueue;
 
+import org.jetbrains.annotations.VisibleForTesting;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -30,9 +32,21 @@ public enum SpotlessRunCleanup {
 
     private static final Cleaner CLEANER = Cleaner.create();
 
+    private static final ConcurrentLinkedQueue<Cleaner.Cleanable> CLEANABLES = new ConcurrentLinkedQueue<>();
+
     public void deleteDirOnCleanup(Object reference, Path path) {
         LOGGER.debug("Registering cleanup for directory: {} -- reference: {}", path, reference);
-        CLEANER.register(reference, new PathCleanup(path));
+        CLEANABLES.add(CLEANER.register(reference, new PathCleanup(path)));
+    }
+
+    @VisibleForTesting
+    public void clearCleanables() {
+        while (!CLEANABLES.isEmpty()) {
+            Cleaner.Cleanable cleanable = CLEANABLES.poll();
+            if (cleanable != null) {
+                cleanable.clean();
+            }
+        }
     }
 
     private record PathCleanup(Path path) implements Runnable {

app/src/test/java/com/diffplug/spotless/cli/core/ExecutionLayoutTest.java

@@ -15,8 +15,12 @@
  */
 package com.diffplug.spotless.cli.core;
 
+import java.io.IOException;
+import java.nio.file.Files;
 import java.nio.file.Path;
 
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.mockito.Mockito;
 
@@ -26,6 +30,19 @@
 
 class ExecutionLayoutTest extends ResourceHarness {
 
+    SpotlessRunCleanup cleanup;
+
+    @BeforeEach
+    void setUp() throws IOException {
+        cleanup = SpotlessRunCleanup.INSTANCE;
+    }
+
+    @AfterEach
+    void cleanup() {
+        cleanup.clearCleanables();
+        cleanup = null;
+    }
+
     @Test
     void itResolvesGradleBuildDir() {
         setFile("settings.gradle").toLines("rootProject.name = 'test'");
@@ -65,6 +82,19 @@ void itResolvesTmpBuildDir() {
                 .startsWith(System.getProperty("java.io.tmpdir"));
     }
 
+    @Test
+    void itCleansUpTmpBuildDir() throws IOException {
+        ExecutionLayout layout = ExecutionLayout.create(fileResolver(), commandLineStream());
+        Path buildDir = layout.buildDir();
+        buildDir.toFile().mkdirs(); // make sure it's ready
+        Path tmpFile = buildDir.resolve("tmpFile.txt");
+        Files.writeString(tmpFile, "Test %s".formatted(buildDir));
+
+        cleanup.clearCleanables();
+
+        assertThat(Files.exists(buildDir)).isFalse();
+    }
+
     private FileResolver fileResolver() {
         return new FileResolver(rootFolder().toPath());
     }