optional commenting range provider and empty comemnt thread factory.

src/vs/vscode.proposed.d.ts

@@ -736,7 +736,7 @@ declare module 'vscode' {
 		range: Range;
 
 		/**
-		 * Label describing the [Comment Thread](#CommentThread)
+		 * The human-readable label describing the [Comment Thread](#CommentThread)
 		 */
 		label?: string;
 
@@ -746,19 +746,24 @@ declare module 'vscode' {
 		comments: Comment[];
 
 		/**
+		 * Optional accept input command
+		 *
 		 * `acceptInputCommand` is the default action rendered on Comment Widget, which is always placed rightmost.
-		 * It will be executed when users submit the comment from keyboard shortcut.
-		 * This action is disabled when the comment editor is empty.
+		 * This command will be invoked when users the user accepts the value in the comment editor.
+		 * This command will disabled when the comment editor is empty.
 		 */
 		acceptInputCommand?: Command;
 
 		/**
+		 * Optional additonal commands.
+		 *
 		 * `additionalCommands` are the secondary actions rendered on Comment Widget.
 		 */
 		additionalCommands?: Command[];
 
 		/**
-		 * Whether the thread should be collapsed or expanded when opening the document. Defaults to Collapsed.
+		 * Whether the thread should be collapsed or expanded when opening the document.
+		 * Defaults to Collapsed.
 		 */
 		collapsibleState?: CommentThreadCollapsibleState;
 		dispose?(): void;
@@ -931,24 +936,49 @@ declare module 'vscode' {
 		value: string;
 	}
 
+	export interface CommentingRangeProvider {
+		provideCommentingRange(document: TextDocument, token: CancellationToken): ProviderResult<Range[]>;
+	}
+
+	export interface EmptyCommentThreadFactory {
+		/**
+		 * The method `createEmptyCommentThread` is called when users attempt to create new comment thread from the gutter or command palette.
+		 * Extensions still need to call `createCommentThread` inside this call when appropriate.
+		 */
+		createEmptyCommentThread(document: TextDocument, range: Range): ProviderResult<void>;
+	}
+
 	export interface CommentController {
+		/**
+		 * The id of this comment controller.
+		 */
 		readonly id: string;
+
+		/**
+		 * The human-readable label of this comment controller.
+		 */
 		readonly label: string;
+
 		/**
-		 * The active (focused) comment input box.
+		 * The active (focused) [comment input box](#CommentInputBox).
 		 */
 		readonly inputBox?: CommentInputBox;
 		createCommentThread(id: string, resource: Uri, range: Range): CommentThread;
+
 		/**
+		 * Optional commenting range provider.
 		 * Provide a list [ranges](#Range) which support commenting to any given resource uri.
-		 *
-		 * @param uri The uri of the resource open in a text editor.
-		 * @param callback, a handler called when users attempt to create a new comment thread, either from the gutter or command palette
-		 * @param token A cancellation token.
-		 * @return A thenable that resolves to a list of commenting ranges or null and undefined if the provider
-		 * does not want to participate or was cancelled.
 		 */
-		registerCommentingRangeProvider(provider: (document: TextDocument, token: CancellationToken) => ProviderResult<Range[]>, callback: (document: TextDocument, range: Range) => void): void;
+		commentingRangeProvider?: CommentingRangeProvider;
+
+		/**
+		 * Optional new comment thread factory.
+		 */
+		emptyCommentThreadFactory: EmptyCommentThreadFactory;
+
+		/**
+		 * Dispose this comment controller.
+		 */
 		dispose(): void;
 	}
 

src/vs/workbench/api/node/extHostComments.ts

@@ -108,19 +108,19 @@ export class ExtHostComments implements ExtHostCommentsShape {
 
 		const document = this._documents.getDocument(URI.revive(uriComponents));
 		return asPromise(() => {
-			return commentController.commentingRangeProvider.provider(document, token);
+			return commentController.commentingRangeProvider.provideCommentingRange(document, token);
 		}).then(ranges => ranges ? ranges.map(extHostTypeConverter.Range.from) : undefined);
 	}
 
 	$createNewCommentWidgetCallback(commentControllerHandle: number, uriComponents: UriComponents, range: IRange, token: CancellationToken): void {
 		const commentController = this._commentControllers.get(commentControllerHandle);
 
-		if (!commentController || !commentController.commentingRangeProvider) {
+		if (!commentController || !commentController.emptyCommentThreadFactory) {
 			return;
 		}
 
 		const document = this._documents.getDocument(URI.revive(uriComponents));
-		commentController.commentingRangeProvider.callback(document, extHostTypeConverter.Range.to(range));
+		commentController.emptyCommentThreadFactory.createEmptyCommentThread(document, extHostTypeConverter.Range.to(range));
 	}
 
 	registerWorkspaceCommentProvider(
@@ -435,16 +435,6 @@ export class ExtHostCommentInputBox implements vscode.CommentInputBox {
 		this._value = input;
 	}
 }
-
-class ExtHostCommentingRangeProvider {
-	constructor(
-		public provider: (document: vscode.TextDocument, token: vscode.CancellationToken) => vscode.ProviderResult<vscode.Range[]>,
-		public callback: (document: vscode.TextDocument, range: vscode.Range) => void
-	) {
-
-	}
-}
-
 class ExtHostCommentController implements vscode.CommentController {
 	get id(): string {
 		return this._id;
@@ -462,16 +452,8 @@ class ExtHostCommentController implements vscode.CommentController {
 	}
 
 	private _threads: Map<number, ExtHostCommentThread> = new Map<number, ExtHostCommentThread>();
-
-	private _commentingRangeProvider: ExtHostCommentingRangeProvider | undefined = undefined;
-
-	get commentingRangeProvider(): ExtHostCommentingRangeProvider | undefined {
-		return this._commentingRangeProvider;
-	}
-
-	set commentingRangeProvider(commentingRangeProvider: ExtHostCommentingRangeProvider | undefined) {
-		this._commentingRangeProvider = commentingRangeProvider;
-	}
+	commentingRangeProvider?: vscode.CommentingRangeProvider;
+	emptyCommentThreadFactory: vscode.EmptyCommentThreadFactory;
 
 	constructor(
 		_extension: IExtensionDescription,
@@ -490,10 +472,6 @@ class ExtHostCommentController implements vscode.CommentController {
 		return commentThread;
 	}
 
-	registerCommentingRangeProvider(provider: (document: vscode.TextDocument, token: vscode.CancellationToken) => vscode.ProviderResult<vscode.Range[]>, callback: (document: vscode.TextDocument, range: vscode.Range) => void) {
-		this._commentingRangeProvider = new ExtHostCommentingRangeProvider(provider, callback);
-	}
-
 	$onCommentWidgetInputChange(input: string) {
 		if (!this.inputBox) {
 			this.inputBox = new ExtHostCommentInputBox(this._proxy, this.handle, input);