Work around issue with getting stale contents from openTextDocument (#3545)

* Work around issue with getting stale contents from openTextDocument

* Avoid calling openTextDocument when creating a new file, and use only writeFile.  Unsubscribe from window activation when settings UI is not visible.

* Switch to using editorTabSize for settings file

Extension/src/LanguageServer/configurations.ts

@@ -173,7 +173,8 @@ export class CppProperties {
             this.propertiesFile = null;
         }
         
-        this.configFileWatcher = vscode.workspace.createFileSystemWatcher(path.join(this.configFolder, this.configurationGlobPattern));
+        let settingsPath: string = path.join(this.configFolder, this.configurationGlobPattern);
+        this.configFileWatcher = vscode.workspace.createFileSystemWatcher(settingsPath);
         this.disposables.push(this.configFileWatcher);
         this.configFileWatcher.onDidCreate((uri) => {
             this.propertiesFile = uri;
@@ -187,7 +188,24 @@ export class CppProperties {
         });
 
         this.configFileWatcher.onDidChange(() => {
-            this.handleConfigurationChange();
+            // If the file is one of the textDocument's vscode is tracking, we need to wait for an
+            // onDidChangeTextDocument event, or we may get old/cached contents when we open it.
+            let alreadyTracking: boolean = false;
+            for (let i: number = 0; i < vscode.workspace.textDocuments.length; i++) {
+                if (vscode.workspace.textDocuments[i].uri.fsPath === settingsPath) {
+                    alreadyTracking = true;
+                    break;
+                }
+            }
+            if (!alreadyTracking) {
+                this.handleConfigurationChange();
+            }
+        });
+
+        vscode.workspace.onDidChangeTextDocument((e: vscode.TextDocumentChangeEvent) => {
+            if (e.document.uri.fsPath === settingsPath) {
+                this.handleConfigurationChange();
+            }
         });
 
         this.handleConfigurationChange();
@@ -681,11 +699,6 @@ export class CppProperties {
                 }
 
                 let fullPathToFile: string = path.join(this.configFolder, "c_cpp_properties.json");
-                let filePath: vscode.Uri = vscode.Uri.file(fullPathToFile).with({ scheme: "untitled" });
-
-                let document: vscode.TextDocument = await vscode.workspace.openTextDocument(filePath);
-
-                let edit: vscode.WorkspaceEdit = new vscode.WorkspaceEdit();
                 if (this.configurationJson) {
                     this.resetToDefaultSettings(true);
                 }
@@ -700,17 +713,9 @@ export class CppProperties {
                 let savedKnownCompilers: KnownCompiler[] = this.configurationJson.configurations[0].knownCompilers;
                 delete this.configurationJson.configurations[0].knownCompilers;
 
-                edit.insert(document.uri, new vscode.Position(0, 0), JSON.stringify(this.configurationJson, null, 4));
-
+                let otherSettings: OtherSettings = new OtherSettings(this.rootUri);
+                await util.writeFileText(fullPathToFile, JSON.stringify(this.configurationJson, null, otherSettings.editorTabSize));
                 this.configurationJson.configurations[0].knownCompilers = savedKnownCompilers;
-                await vscode.workspace.applyEdit(edit);
-
-                // Fix for issue 163
-                // https://github.com/Microsoft/vscppsamples/issues/163
-                // Save the file to disk so that when the user tries to re-open the file it exists.
-                // Before this fix the file existed but was unsaved, so we went through the same
-                // code path and reapplied the edit.
-                await document.save();
 
                 this.propertiesFile = vscode.Uri.file(path.join(this.configFolder, "c_cpp_properties.json"));
 
@@ -1118,7 +1123,8 @@ export class CppProperties {
 
     private writeToJson(): void {
         console.assert(this.propertiesFile);
-        fs.writeFileSync(this.propertiesFile.fsPath, JSON.stringify(this.configurationJson, null, 4));
+        let otherSettings: OtherSettings = new OtherSettings(this.rootUri);
+        fs.writeFileSync(this.propertiesFile.fsPath, JSON.stringify(this.configurationJson, null, otherSettings.editorTabSize));
     }
 
     public checkCppProperties(): void {

Extension/src/LanguageServer/settingsPanel.ts

@@ -36,8 +36,7 @@ export class SettingsPanel {
         this.configValues = { name: undefined };
         this.disposable = vscode.Disposable.from(
             this.settingsPanelActivated,
-            this.configValuesChanged,
-            vscode.window.onDidChangeWindowState(this.onWindowStateChanged, this)
+            this.configValuesChanged
         );
     }
 
@@ -75,7 +74,8 @@ export class SettingsPanel {
             this.panel,
             this.panel.onDidDispose(this.onPanelDisposed, this),
             this.panel.onDidChangeViewState(this.onViewStateChanged, this),
-            this.panel.webview.onDidReceiveMessage(this.onMessageReceived, this)
+            this.panel.webview.onDidReceiveMessage(this.onMessageReceived, this),
+            vscode.window.onDidChangeWindowState(this.onWindowStateChanged, this)
         );
 
         this.panel.webview.html = this.getHtml();