DAS plugins: handle added, modified, removed files

Change-Id: Idc8cd1378e5a7e8c8191dfad9a37edd990e88120
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/446920
Reviewed-by: Brian Wilkerson <[email protected]>
Commit-Queue: Samuel Rawlins <[email protected]>

Author: srawlins

pkg/analysis_server_plugin/lib/src/plugin_server.dart

@@ -467,7 +467,9 @@ class PluginServer {
     switch (request.method) {
       case protocol.ANALYSIS_REQUEST_GET_NAVIGATION:
       case protocol.ANALYSIS_REQUEST_HANDLE_WATCH_EVENTS:
-        result = null;
+        var params =
+            protocol.AnalysisHandleWatchEventsParams.fromRequest(request);
+        result = await _handleAnalysisWatchEvents(params);
 
       case protocol.ANALYSIS_REQUEST_SET_CONTEXT_ROOTS:
         var params =
@@ -608,21 +610,55 @@ class PluginServer {
 
       changedPaths.add(path);
     });
-    await _handleContentChanged(changedPaths.toList());
+    await _handleContentChanged(modifiedPaths: changedPaths.toList());
     return protocol.AnalysisUpdateContentResult();
   }
 
-  /// Handles the fact that files with [paths] were changed.
-  Future<void> _handleContentChanged(List<String> paths) async {
+  /// Handles an 'analysis.handleWatchEvents' request.
+  Future<protocol.AnalysisHandleWatchEventsResult> _handleAnalysisWatchEvents(
+      protocol.AnalysisHandleWatchEventsParams parameters) async {
+    final addedPaths = parameters.events
+        .where((e) => e.type == protocol.WatchEventType.ADD)
+        .map((e) => e.path)
+        .toList();
+    final modifiedPaths = parameters.events
+        .where((e) => e.type == protocol.WatchEventType.MODIFY)
+        .map((e) => e.path)
+        .toList();
+    final removedPaths = parameters.events
+        .where((e) => e.type == protocol.WatchEventType.REMOVE)
+        .map((e) => e.path)
+        .toList();
+
+    await _handleContentChanged(
+      addedPaths: addedPaths,
+      modifiedPaths: modifiedPaths,
+      removedPaths: removedPaths,
+    );
+
+    return protocol.AnalysisHandleWatchEventsResult();
+  }
+
+  /// Handles added files, modified files, and removed files.
+  Future<void> _handleContentChanged(
+      {List<String> addedPaths = const [],
+      List<String> modifiedPaths = const [],
+      List<String> removedPaths = const []}) async {
     if (_contextCollection case var contextCollection?) {
       _channel.sendNotification(
           protocol.PluginStatusParams(analysis: protocol.AnalysisStatus(true))
               .toNotification());
       await _forAnalysisContexts(contextCollection, (analysisContext) async {
-        for (var path in paths) {
+        for (var path in modifiedPaths) {
+          analysisContext.changeFile(path);
+        }
+        for (var path in removedPaths) {
           analysisContext.changeFile(path);
         }
-        var affected = await analysisContext.applyPendingFileChanges();
+        var affected = [
+          ...await analysisContext.applyPendingFileChanges(),
+          ...addedPaths,
+        ];
         await _handleAffectedFiles(
             analysisContext: analysisContext, paths: affected);
       });

pkg/analysis_server_plugin/test/src/plugin_server_test.dart

@@ -300,6 +300,62 @@ bool b = false;
     expect(params.errors, isEmpty);
   }
 
+  Future<void> test_watchEvent_add() async {
+    writeAnalysisOptionsWithPlugin();
+    await channel
+        .sendRequest(protocol.AnalysisSetContextRootsParams([contextRoot]));
+
+    var paramsQueue = _analysisErrorsParams;
+
+    newFile(filePath, 'bool b = false;');
+
+    await channel.sendRequest(protocol.AnalysisHandleWatchEventsParams(
+        [WatchEvent(WatchEventType.ADD, filePath)]));
+
+    var params = await paramsQueue.next;
+    expect(params.errors, hasLength(1));
+    _expectAnalysisError(params.errors.single, message: 'No bools message');
+  }
+
+  Future<void> test_watchEvent_modify() async {
+    writeAnalysisOptionsWithPlugin();
+    newFile(filePath, 'int b = 7;');
+    await channel
+        .sendRequest(protocol.AnalysisSetContextRootsParams([contextRoot]));
+
+    var paramsQueue = _analysisErrorsParams;
+    var params = await paramsQueue.next;
+    expect(params.errors, isEmpty);
+
+    newFile(filePath, 'bool b = false;');
+
+    await channel.sendRequest(protocol.AnalysisHandleWatchEventsParams(
+        [WatchEvent(WatchEventType.MODIFY, filePath)]));
+
+    params = await paramsQueue.next;
+    expect(params.errors, hasLength(1));
+    _expectAnalysisError(params.errors.single, message: 'No bools message');
+  }
+
+  Future<void> test_watchEvent_remove() async {
+    writeAnalysisOptionsWithPlugin();
+    newFile(filePath, 'int b = 7;');
+    await channel
+        .sendRequest(protocol.AnalysisSetContextRootsParams([contextRoot]));
+
+    var paramsQueue = _analysisErrorsParams;
+    var params = await paramsQueue.next;
+    expect(params.errors, isEmpty);
+
+    deleteFile(filePath);
+
+    await channel.sendRequest(protocol.AnalysisHandleWatchEventsParams(
+        [WatchEvent(WatchEventType.REMOVE, filePath)]));
+
+    params = await paramsQueue.next;
+    expect(params.errors, isEmpty);
+  }
+
   void writeAnalysisOptionsWithPlugin(
       [Map<String, String> diagnosticConfiguration = const {}]) {
     var buffer = StringBuffer('''