Access active source control provider

src/vs/vscode.proposed.d.ts

@@ -256,6 +256,19 @@ declare module 'vscode' {
 
 	//#endregion
 
+	//#region scm
+	export namespace scm {
+		/**
+		 * The currently active [source control](#SourceControl).
+		 */
+		export let activeSourceControl: SourceControl | undefined;
+		/**
+		 * An [event](#Event) which fires when the active [source control](#SourceControl) has changed.
+		 */
+		export const onDidChangeActiveSourceControl: Event<SourceControl>;
+	}
+	//#endregion
+
 	//#region Comments
 	/**
 	 * Comments provider related APIs are still in early stages, they may be changed significantly during our API experiments.

src/vs/workbench/api/electron-browser/mainThreadSCM.ts

@@ -263,6 +263,8 @@ export class MainThreadSCM implements MainThreadSCMShape {
 	private _proxy: ExtHostSCMShape;
 	private _repositories: { [handle: number]: ISCMRepository; } = Object.create(null);
 	private _inputDisposables: { [handle: number]: IDisposable; } = Object.create(null);
+	private _focusDisposables: { [handle: number]: IDisposable; } = Object.create(null);
+	private _focusedRepository: ISCMRepository | undefined;
 	private _disposables: IDisposable[] = [];
 
 	constructor(
@@ -281,6 +283,10 @@ export class MainThreadSCM implements MainThreadSCMShape {
 			.forEach(id => this._inputDisposables[id].dispose());
 		this._inputDisposables = Object.create(null);
 
+		Object.keys(this._focusDisposables)
+			.forEach(id => this._focusDisposables[id].dispose());
+		this._focusDisposables = Object.create(null);
+
 		this._disposables = dispose(this._disposables);
 	}
 
@@ -289,8 +295,21 @@ export class MainThreadSCM implements MainThreadSCMShape {
 		const repository = this.scmService.registerSCMProvider(provider);
 		this._repositories[handle] = repository;
 
+		if (!this._focusedRepository) {
+			this._focusedRepository = repository;
+			this._proxy.$acceptActiveSourceControlChange(handle);
+		}
+
 		const inputDisposable = repository.input.onDidChange(value => this._proxy.$onInputBoxValueChange(handle, value));
 		this._inputDisposables[handle] = inputDisposable;
+
+		const focusDisposable = repository.onDidFocus(_ => this.onDidFocus(handle, repository));
+		this._focusDisposables[handle] = focusDisposable;
+	}
+
+	onDidFocus(handle: number, repository: ISCMRepository) {
+		this._focusedRepository = repository;
+		this._proxy.$acceptActiveSourceControlChange(handle);
 	}
 
 	$updateSourceControl(handle: number, features: SCMProviderFeatures): void {
@@ -314,6 +333,9 @@ export class MainThreadSCM implements MainThreadSCMShape {
 		this._inputDisposables[handle].dispose();
 		delete this._inputDisposables[handle];
 
+		this._focusDisposables[handle].dispose();
+		delete this._focusDisposables[handle];
+
 		repository.dispose();
 		delete this._repositories[handle];
 	}

src/vs/workbench/api/node/extHost.api.impl.ts

@@ -566,6 +566,12 @@ export function createApiFactory(
 			get inputBox() {
 				return extHostSCM.getLastInputBox(extension);
 			},
+			get activeSourceControl() {
+				return extHostSCM.activeSourceControl;
+			},
+			get onDidChangeActiveSourceControl() {
+				return extHostSCM.onDidChangeActiveSourceControl;
+			},
 			createSourceControl(id: string, label: string, rootUri?: vscode.Uri) {
 				return extHostSCM.createSourceControl(extension, id, label, rootUri);
 			}

src/vs/workbench/api/node/extHost.protocol.ts

@@ -782,6 +782,7 @@ export interface ExtHostTerminalServiceShape {
 export interface ExtHostSCMShape {
 	$provideOriginalResource(sourceControlHandle: number, uri: UriComponents): TPromise<UriComponents>;
 	$onInputBoxValueChange(sourceControlHandle: number, value: string): TPromise<void>;
+	$acceptActiveSourceControlChange(sourceControlHandle: number): TPromise<void>;
 	$executeResourceCommand(sourceControlHandle: number, groupHandle: number, handle: number): TPromise<void>;
 	$validateInput(sourceControlHandle: number, value: string, cursorPosition: number): TPromise<[string, number] | undefined>;
 }

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

@@ -467,9 +467,12 @@ export class ExtHostSCM implements ExtHostSCMShape {
 	private _proxy: MainThreadSCMShape;
 	private _sourceControls: Map<ProviderHandle, ExtHostSourceControl> = new Map<ProviderHandle, ExtHostSourceControl>();
 	private _sourceControlsByExtension: Map<string, ExtHostSourceControl[]> = new Map<string, ExtHostSourceControl[]>();
-
-	private _onDidChangeActiveProvider = new Emitter<vscode.SourceControl>();
-	get onDidChangeActiveProvider(): Event<vscode.SourceControl> { return this._onDidChangeActiveProvider.event; }
+	private _activeSourceControl: vscode.SourceControl | undefined;
+	get activeSourceControl(): vscode.SourceControl | undefined {
+		return this._activeSourceControl;
+	}
+	private _onDidChangeActiveSourceControl = new Emitter<vscode.SourceControl>();
+	get onDidChangeActiveSourceControl(): Event<vscode.SourceControl> { return this._onDidChangeActiveSourceControl.event; }
 
 	constructor(
 		mainContext: IMainContext,
@@ -568,6 +571,22 @@ export class ExtHostSCM implements ExtHostSCMShape {
 		return TPromise.as(null);
 	}
 
+	$acceptActiveSourceControlChange(sourceControlHandle: number): TPromise<void> {
+		this.logService.trace('ExtHostSCM#$acceptActiveSourceControlChange', sourceControlHandle);
+		const sourceControl = this._sourceControls.get(sourceControlHandle);
+
+		if (!sourceControl) {
+			return TPromise.as(null);
+		}
+
+		if (this._activeSourceControl !== sourceControl) {
+			this._activeSourceControl = sourceControl;
+			this._onDidChangeActiveSourceControl.fire(this.activeSourceControl);
+		}
+
+		return TPromise.as(null);
+	}
+
 	async $executeResourceCommand(sourceControlHandle: number, groupHandle: number, handle: number): TPromise<void> {
 		this.logService.trace('ExtHostSCM#$executeResourceCommand', sourceControlHandle, groupHandle, handle);