Don't write locks if both the locks and props change

changelog/@unreleased/pr-67.v2.yml

@@ -0,0 +1,5 @@
+type: fix
+fix:
+  description: Don't write locks if both the locks and props change
+  links:
+  - https://github.com/palantir/gradle-consistent-versions-idea-plugin/pull/67

gradle-consistent-versions-idea-plugin/src/main/java/com/palantir/gradle/versions/intellij/DebouncingAsyncFileListener.java

@@ -0,0 +1,85 @@
+/*
+ * (c) Copyright 2024 Palantir Technologies Inc. All rights reserved.
+ *
+ * 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.palantir.gradle.versions.intellij;
+
+import com.intellij.openapi.Disposable;
+import com.intellij.openapi.vfs.AsyncFileListener;
+import com.intellij.openapi.vfs.newvfs.events.VFileEvent;
+import com.intellij.util.Alarm;
+import com.intellij.util.SingleAlarm;
+import java.util.ArrayList;
+import java.util.List;
+import org.jetbrains.annotations.Nullable;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public final class DebouncingAsyncFileListener implements AsyncFileListener, Disposable {
+    private static final Logger log = LoggerFactory.getLogger(DebouncingAsyncFileListener.class);
+
+    private final AsyncFileListener delegate;
+    private final SingleAlarm alarm;
+    private final Object lock = new Object();
+
+    private final List<VFileEvent> bufferedEvents = new ArrayList<>();
+    private boolean isDisposed = false;
+
+    DebouncingAsyncFileListener(AsyncFileListener delegate, int debounceDelayMillis) {
+        this.delegate = delegate;
+        this.alarm = new SingleAlarm(this::processEvents, debounceDelayMillis, this, Alarm.ThreadToUse.POOLED_THREAD);
+    }
+
+    @Nullable
+    @Override
+    public ChangeApplier prepareChange(List<? extends VFileEvent> events) {
+        synchronized (lock) {
+            if (isDisposed) {
+                return null;
+            }
+            log.debug("Received events: {}", events);
+            bufferedEvents.addAll(events);
+            alarm.request();
+        }
+        return null;
+    }
+
+    private void processEvents() {
+        List<VFileEvent> eventsToProcess;
+        synchronized (lock) {
+            if (isDisposed) {
+                return;
+            }
+            eventsToProcess = new ArrayList<>(bufferedEvents);
+            bufferedEvents.clear();
+        }
+        log.debug("Processing debounced events: {}", eventsToProcess);
+        AsyncFileListener.ChangeApplier applier = delegate.prepareChange(eventsToProcess);
+        if (applier != null) {
+            applier.afterVfsChange();
+        }
+    }
+
+    @Override
+    public void dispose() {
+        synchronized (lock) {
+            if (isDisposed) {
+                return;
+            }
+            isDisposed = true;
+            alarm.cancelAllRequests();
+        }
+    }
+}

gradle-consistent-versions-idea-plugin/src/main/java/com/palantir/gradle/versions/intellij/VersionPropsFileListener.java

@@ -17,6 +17,7 @@
 package com.palantir.gradle.versions.intellij;
 
 import com.intellij.execution.executors.DefaultRunExecutor;
+import com.intellij.openapi.application.ApplicationManager;
 import com.intellij.openapi.components.ComponentManager;
 import com.intellij.openapi.externalSystem.importing.ImportSpecBuilder;
 import com.intellij.openapi.externalSystem.model.execution.ExternalSystemTaskExecutionSettings;
@@ -25,6 +26,7 @@
 import com.intellij.openapi.externalSystem.util.ExternalSystemUtil;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.project.ProjectManager;
+import com.intellij.openapi.util.Computable;
 import com.intellij.openapi.vfs.AsyncFileListener;
 import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.openapi.vfs.newvfs.events.VFileContentChangeEvent;
@@ -56,6 +58,12 @@ public ChangeApplier prepareChange(List<? extends VFileEvent> events) {
                 .filter(event -> "versions.props".equals(event.getFile().getName()))
                 .toList();
 
+        List<VFileContentChangeEvent> versionLockEvents = events.stream()
+                .filter(event -> event instanceof VFileContentChangeEvent)
+                .map(event -> (VFileContentChangeEvent) event)
+                .filter(event -> "versions.lock".equals(event.getFile().getName()))
+                .toList();
+
         if (versionPropsEvents.isEmpty()) {
             return null;
         }
@@ -64,9 +72,12 @@ public ChangeApplier prepareChange(List<? extends VFileEvent> events) {
                         ProjectManager.getInstance().getOpenProjects())
                 .filter(Project::isInitialized)
                 .filter(Predicate.not(ComponentManager::isDisposed))
+                .filter(project -> project.getBasePath() != null)
                 .filter(project -> versionPropsEvents.stream()
                         .anyMatch(event -> event.getPath().startsWith(project.getBasePath())
                                 && !isFileMalformed(project, event.getFile())))
+                .filter(project -> versionLockEvents.stream()
+                        .noneMatch(event -> event.getPath().startsWith(project.getBasePath())))
                 .toList();
 
         return new ChangeApplier() {
@@ -138,12 +149,14 @@ private void refreshProject(Project project, ImportSpecBuilder importSpec) {
     }
 
     private static boolean isFileMalformed(Project project, VirtualFile file) {
-        PsiFile psiFile = PsiManager.getInstance(project).findFile(file);
+        return ApplicationManager.getApplication().runReadAction((Computable<Boolean>) () -> {
+            PsiFile psiFile = PsiManager.getInstance(project).findFile(file);
 
-        if (psiFile == null || !(psiFile.getFileType() instanceof VersionPropsFileType)) {
-            return true;
-        }
+            if (psiFile == null || !(psiFile.getFileType() instanceof VersionPropsFileType)) {
+                return true;
+            }
 
-        return PsiTreeUtil.hasErrorElements(psiFile);
+            return PsiTreeUtil.hasErrorElements(psiFile);
+        });
     }
 }

gradle-consistent-versions-idea-plugin/src/main/java/com/palantir/gradle/versions/intellij/VersionPropsListenerRegistrar.java

@@ -0,0 +1,38 @@
+/*
+ * (c) Copyright 2024 Palantir Technologies Inc. All rights reserved.
+ *
+ * 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.palantir.gradle.versions.intellij;
+
+import com.intellij.openapi.vfs.AsyncFileListener;
+import com.intellij.openapi.vfs.newvfs.events.VFileEvent;
+import java.util.List;
+import org.jetbrains.annotations.Nullable;
+
+public final class VersionPropsListenerRegistrar implements AsyncFileListener {
+
+    private final DebouncingAsyncFileListener debouncedListener;
+
+    VersionPropsListenerRegistrar() {
+        AsyncFileListener versionPropsListener = new VersionPropsFileListener();
+        debouncedListener = new DebouncingAsyncFileListener(versionPropsListener, 250);
+    }
+
+    @Nullable
+    @Override
+    public ChangeApplier prepareChange(List<? extends VFileEvent> events) {
+        return debouncedListener.prepareChange(events);
+    }
+}

gradle-consistent-versions-idea-plugin/src/main/resources/META-INF/plugin.xml

@@ -50,7 +50,7 @@
     <completion.contributor language="VersionProps"
                             implementationClass="com.palantir.gradle.versions.intellij.FolderCompletionContributor"/>
     <lang.commenter language="VersionProps" implementationClass="com.palantir.gradle.versions.intellij.VersionPropsCommenter"/>
-    <vfs.asyncListener implementation="com.palantir.gradle.versions.intellij.VersionPropsFileListener"/>
+    <vfs.asyncListener implementation="com.palantir.gradle.versions.intellij.VersionPropsListenerRegistrar"/>
     <annotator language="VersionProps" implementationClass="com.palantir.gradle.versions.intellij.CommentAnnotator" />
     <externalSystemTaskNotificationListener implementation="com.palantir.gradle.versions.intellij.LoadCacheOnGradleProjectRefresh" />
     <applicationService serviceImplementation="com.palantir.gradle.versions.intellij.GradleCacheExplorer" />