Fix issues with remapping of .C files (#13476)

Author: Colengms

Extension/src/LanguageServer/protocolFilter.ts

@@ -11,6 +11,7 @@ import * as util from '../common';
 import { logAndReturn } from '../Utility/Async/returns';
 import { Client } from './client';
 import { clients } from './extension';
+import { hasFileAssociation } from './settings';
 import { shouldChangeFromCToCpp } from './utils';
 
 export const RequestCancelled: number = -32800;
@@ -30,21 +31,22 @@ export function createProtocolFilter(): Middleware {
                     client.TrackedDocuments.set(uriString, document);
                     // Work around vscode treating ".C" or ".H" as c, by adding this file name to file associations as cpp
                     if (document.languageId === "c" && shouldChangeFromCToCpp(document)) {
-                        const baseFileName: string = path.basename(document.fileName);
-                        const mappingString: string = baseFileName + "@" + document.fileName;
-                        client.addFileAssociations(mappingString, "cpp");
-                        client.sendDidChangeSettings();
-                        // This will cause the file to be closed and reopened.
-                        void vscode.languages.setTextDocumentLanguage(document, "cpp");
-                        return;
+                        // Don't override the user's setting.
+                        if (!hasFileAssociation(path.basename(document.uri.fsPath))) {
+                            const baseFileName: string = path.basename(document.fileName);
+                            const mappingString: string = baseFileName + "@" + document.fileName;
+                            client.addFileAssociations(mappingString, "cpp");
+                            client.sendDidChangeSettings();
+                            // The following will cause the file to be closed and reopened.
+                            void vscode.languages.setTextDocumentLanguage(document, "cpp");
+                            return;
+                        }
                     }
                     // client.takeOwnership() will call client.TrackedDocuments.add() again, but that's ok. It's a Set.
                     client.takeOwnership(document);
                     void sendMessage(document);
-                    const editor: vscode.TextEditor | undefined = vscode.window.visibleTextEditors.find(editor => editor.document === document);
-                    if (editor) {
-                        client.onDidChangeVisibleTextEditors([editor]).catch(logAndReturn.undefined);
-                    }
+                    const cppEditors: vscode.TextEditor[] = vscode.window.visibleTextEditors.filter(e => util.isCpp(e.document));
+                    client.onDidChangeVisibleTextEditors(cppEditors).catch(logAndReturn.undefined);
                 }
             }
         },

Extension/src/LanguageServer/settings.ts

@@ -1099,3 +1099,17 @@ export class OtherSettings {
     public get searchExclude(): Excludes { return this.getAsExcludes("search", "exclude", this.defaultSearchExcludes, this.resource); }
     public get workbenchSettingsEditor(): string { return this.getAsString("workbench.settings", "editor", this.resource, "ui"); }
 }
+
+export function hasFileAssociation(fileName: string): boolean {
+    const otherSettings: OtherSettings = new OtherSettings();
+    const associations: Associations = otherSettings.filesAssociations;
+    if (associations[fileName]) {
+        return true;
+    }
+    for (const pattern in associations) {
+        if (pattern.startsWith('*.') && fileName.endsWith(pattern.slice(1))) {
+            return true;
+        }
+    }
+    return false;
+}