Add "view file text" command to debug sync issues

editors/code/src/commands.ts

@@ -432,6 +432,54 @@ export function viewHir(ctx: Ctx): Cmd {
     };
 }
 
+export function viewFileText(ctx: Ctx): Cmd {
+    const tdcp = new class implements vscode.TextDocumentContentProvider {
+        readonly uri = vscode.Uri.parse('rust-analyzer://viewFileText/file.rs');
+        readonly eventEmitter = new vscode.EventEmitter<vscode.Uri>();
+        constructor() {
+            vscode.workspace.onDidChangeTextDocument(this.onDidChangeTextDocument, this, ctx.subscriptions);
+            vscode.window.onDidChangeActiveTextEditor(this.onDidChangeActiveTextEditor, this, ctx.subscriptions);
+        }
+
+        private onDidChangeTextDocument(event: vscode.TextDocumentChangeEvent) {
+            if (isRustDocument(event.document)) {
+                // We need to order this after language server updates, but there's no API for that.
+                // Hence, good old sleep().
+                void sleep(10).then(() => this.eventEmitter.fire(this.uri));
+            }
+        }
+        private onDidChangeActiveTextEditor(editor: vscode.TextEditor | undefined) {
+            if (editor && isRustEditor(editor)) {
+                this.eventEmitter.fire(this.uri);
+            }
+        }
+
+        provideTextDocumentContent(_uri: vscode.Uri, ct: vscode.CancellationToken): vscode.ProviderResult<string> {
+            const rustEditor = ctx.activeRustEditor;
+            const client = ctx.client;
+            if (!rustEditor || !client) return '';
+
+            const params = client.code2ProtocolConverter.asTextDocumentIdentifier(rustEditor.document);
+            return client.sendRequest(ra.viewFileText, params, ct);
+        }
+
+        get onDidChange(): vscode.Event<vscode.Uri> {
+            return this.eventEmitter.event;
+        }
+    };
+
+    ctx.pushCleanup(vscode.workspace.registerTextDocumentContentProvider('rust-analyzer', tdcp));
+
+    return async () => {
+        const document = await vscode.workspace.openTextDocument(tdcp.uri);
+        tdcp.eventEmitter.fire(tdcp.uri);
+        void await vscode.window.showTextDocument(document, {
+            viewColumn: vscode.ViewColumn.Two,
+            preserveFocus: true
+        });
+    };
+}
+
 export function viewItemTree(ctx: Ctx): Cmd {
     const tdcp = new class implements vscode.TextDocumentContentProvider {
         readonly uri = vscode.Uri.parse('rust-analyzer://viewItemTree/itemtree.rs');

editors/code/src/lsp_ext.ts

@@ -36,6 +36,8 @@ export const syntaxTree = new lc.RequestType<SyntaxTreeParams, string, void>("ru
 
 export const viewHir = new lc.RequestType<lc.TextDocumentPositionParams, string, void>("rust-analyzer/viewHir");
 
+export const viewFileText = new lc.RequestType<lc.TextDocumentIdentifier, string, void>("rust-analyzer/viewFileText");
+
 export interface ViewItemTreeParams {
     textDocument: lc.TextDocumentIdentifier;
 }

editors/code/src/main.ts

@@ -114,6 +114,7 @@ async function initCommonContext(context: vscode.ExtensionContext, ctx: Ctx) {
     ctx.registerCommand('parentModule', commands.parentModule);
     ctx.registerCommand('syntaxTree', commands.syntaxTree);
     ctx.registerCommand('viewHir', commands.viewHir);
+    ctx.registerCommand('viewFileText', commands.viewFileText);
     ctx.registerCommand('viewItemTree', commands.viewItemTree);
     ctx.registerCommand('viewCrateGraph', commands.viewCrateGraph);
     ctx.registerCommand('viewFullCrateGraph', commands.viewFullCrateGraph);