chore: cleanup temp-dirs

Author: simschla

app/src/main/java/com/diffplug/spotless/cli/SpotlessCLI.java

@@ -35,6 +35,7 @@
 import com.diffplug.spotless.cli.core.FileResolver;
 import com.diffplug.spotless.cli.core.SpotlessActionContext;
 import com.diffplug.spotless.cli.core.SpotlessCommandLineStream;
+import com.diffplug.spotless.cli.core.SpotlessRunCleanup;
 import com.diffplug.spotless.cli.core.TargetFileTypeInferer;
 import com.diffplug.spotless.cli.core.TargetResolver;
 import com.diffplug.spotless.cli.execution.FormatterStepsSupplier;
@@ -98,6 +99,8 @@ public class SpotlessCLI implements SpotlessAction, SpotlessCommand, SpotlessAct
 
     private @NotNull Output output;
 
+    private final SpotlessRunCleanup spotlessRunCleanup = SpotlessRunCleanup.INSTANCE; // just keep a reference here
+
     @CommandLine.Option(
             names = {"--mode", "-m"},
             defaultValue = "APPLY",

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

@@ -69,9 +69,6 @@ public Optional<Path> find(@Nullable Path searchPath) {
         if (found.toFile().canRead()) {
             return Optional.of(found);
         }
-        if (searchPath.toFile().canRead()) {
-            return Optional.of(searchPath);
-        }
         return Optional.empty();
     }
 
@@ -92,6 +89,7 @@ public Path buildDir() {
         }
         Path tempBuildDir = tempBuildDir();
         LOGGER.info("Using temporary build directory as buildDir: {}", tempBuildDir);
+        SpotlessRunCleanup.INSTANCE.deleteDirOnCleanup(commandLineStream, tempBuildDir);
         return tempBuildDir;
     }
 

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

@@ -0,0 +1,65 @@
+/*
+ * Copyright 2025 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.cli.core;
+
+import java.lang.ref.Cleaner;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Comparator;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public enum SpotlessRunCleanup {
+    INSTANCE;
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(SpotlessRunCleanup.class);
+
+    private static final Cleaner CLEANER = Cleaner.create();
+
+    public void deleteDirOnCleanup(Object reference, Path path) {
+        LOGGER.debug("Registering cleanup for directory: {} -- reference: {}", path, reference);
+        CLEANER.register(reference, new PathCleanup(path));
+    }
+
+    private record PathCleanup(Path path) implements Runnable {
+
+        @Override
+        public void run() {
+            // delete the directory
+            deleteDir();
+        }
+
+        private void deleteDir() {
+            if (!Files.exists(path)) {
+                LOGGER.debug("Directory does not exist, nothing to delete: {}", path);
+                return; // Directory does not exist, nothing to delete
+            }
+            LOGGER.info("Deleting directory: {}", path);
+            try {
+                Files.walk(path).sorted(Comparator.reverseOrder()).forEach(file -> {
+                    try {
+                        Files.delete(file);
+                    } catch (Exception e) {
+                        throw new RuntimeException("Failed to delete file: " + file, e);
+                    }
+                });
+            } catch (Exception e) {
+                LOGGER.warn("Failed to delete directory: {}", path, e);
+            }
+        }
+    }
+}