Make sure the same GitHub account is used until we support multiple GH accounts

extensions/github-authentication/src/common/errors.ts

@@ -8,3 +8,7 @@ export const TIMED_OUT_ERROR = 'Timed out';
 // These error messages are internal and should not be shown to the user in any way.
 export const USER_CANCELLATION_ERROR = 'User Cancelled';
 export const NETWORK_ERROR = 'network error';
+
+// This is the error message that we throw if the login was cancelled for any reason. Extensions
+// calling `getSession` can handle this error to know that the user cancelled the login.
+export const CANCELLATION_ERROR = 'Cancelled';

extensions/github-authentication/src/flows.ts

@@ -68,6 +68,7 @@ interface IFlowTriggerOptions {
 	callbackUri: Uri;
 	uriHandler: UriEventHandler;
 	enterpriseUri?: Uri;
+	existingLogin?: string;
 }
 
 interface IFlow {
@@ -149,7 +150,8 @@ const allFlows: IFlow[] = [
 			nonce,
 			callbackUri,
 			uriHandler,
-			enterpriseUri
+			enterpriseUri,
+			existingLogin
 		}: IFlowTriggerOptions): Promise<string> {
 			logger.info(`Trying without local server... (${scopes})`);
 			return await window.withProgress<string>({
@@ -169,6 +171,9 @@ const allFlows: IFlow[] = [
 					['scope', scopes],
 					['state', encodeURIComponent(callbackUri.toString(true))]
 				]);
+				if (existingLogin) {
+					searchParams.append('login', existingLogin);
+				}
 
 				// The extra toString, parse is apparently needed for env.openExternal
 				// to open the correct URL.
@@ -215,7 +220,8 @@ const allFlows: IFlow[] = [
 			baseUri,
 			redirectUri,
 			logger,
-			enterpriseUri
+			enterpriseUri,
+			existingLogin
 		}: IFlowTriggerOptions): Promise<string> {
 			logger.info(`Trying with local server... (${scopes})`);
 			return await window.withProgress<string>({
@@ -232,6 +238,9 @@ const allFlows: IFlow[] = [
 					['redirect_uri', redirectUri.toString(true)],
 					['scope', scopes],
 				]);
+				if (existingLogin) {
+					searchParams.append('login', existingLogin);
+				}
 
 				const loginUrl = baseUri.with({
 					path: '/login/oauth/authorize',

extensions/github-authentication/src/github.ts

@@ -11,7 +11,7 @@ import { PromiseAdapter, arrayEquals, promiseFromEvent } from './common/utils';
 import { ExperimentationTelemetry } from './common/experimentationService';
 import { Log } from './common/logger';
 import { crypto } from './node/crypto';
-import { TIMED_OUT_ERROR, USER_CANCELLATION_ERROR } from './common/errors';
+import { CANCELLATION_ERROR, TIMED_OUT_ERROR, USER_CANCELLATION_ERROR } from './common/errors';
 
 interface SessionData {
 	id: string;
@@ -296,13 +296,44 @@ export class GitHubAuthenticationProvider implements vscode.AuthenticationProvid
 				scopes: JSON.stringify(scopes),
 			});
 
+			const sessions = await this._sessionsPromise;
 
 			const scopeString = sortedScopes.join(' ');
-			const token = await this._githubServer.login(scopeString);
+			const existingLogin = sessions[0]?.account.label;
+			const token = await this._githubServer.login(scopeString, existingLogin);
 			const session = await this.tokenToSession(token, scopes);
 			this.afterSessionLoad(session);
 
-			const sessions = await this._sessionsPromise;
+			if (sessions.some(s => s.id !== session.id)) {
+				const otherAccountsIndexes = new Array<number>();
+				const otherAccountsLabels = new Set<string>();
+				for (let i = 0; i < sessions.length; i++) {
+					if (sessions[i].id !== session.id) {
+						otherAccountsIndexes.push(i);
+						otherAccountsLabels.add(sessions[i].account.label);
+					}
+				}
+				const proceed = vscode.l10n.t("Continue");
+				const labelstr = [...otherAccountsLabels].join(', ');
+				const result = await vscode.window.showInformationMessage(
+					vscode.l10n.t({
+						message: "You are logged into another account already ({0}).\n\nDo you want to log out of that account and log in to '{1}' instead?",
+						comment: ['{0} is a comma-separated list of account names. {1} is the account name to log into.'],
+						args: [labelstr, session.account.label]
+					}),
+					{ modal: true },
+					proceed
+				);
+				if (result !== proceed) {
+					throw new Error(CANCELLATION_ERROR);
+				}
+
+				// Remove other accounts
+				for (const i of otherAccountsIndexes) {
+					sessions.splice(i, 1);
+				}
+			}
+
 			const sessionIndex = sessions.findIndex(s => s.id === session.id || arrayEquals([...s.scopes].sort(), sortedScopes));
 			if (sessionIndex > -1) {
 				sessions.splice(sessionIndex, 1, session);

extensions/github-authentication/src/githubServer.ts

@@ -11,19 +11,15 @@ import { isSupportedClient, isSupportedTarget } from './common/env';
 import { crypto } from './node/crypto';
 import { fetching } from './node/fetch';
 import { ExtensionHost, GitHubTarget, getFlows } from './flows';
-import { NETWORK_ERROR, USER_CANCELLATION_ERROR } from './common/errors';
+import { CANCELLATION_ERROR, NETWORK_ERROR, USER_CANCELLATION_ERROR } from './common/errors';
 import { Config } from './config';
 import { base64Encode } from './node/buffer';
 
-// This is the error message that we throw if the login was cancelled for any reason. Extensions
-// calling `getSession` can handle this error to know that the user cancelled the login.
-const CANCELLATION_ERROR = 'Cancelled';
-
 const REDIRECT_URL_STABLE = 'https://vscode.dev/redirect';
 const REDIRECT_URL_INSIDERS = 'https://insiders.vscode.dev/redirect';
 
 export interface IGitHubServer {
-	login(scopes: string): Promise<string>;
+	login(scopes: string, existingLogin?: string): Promise<string>;
 	logout(session: vscode.AuthenticationSession): Promise<void>;
 	getUserInfo(token: string): Promise<{ id: string; accountName: string }>;
 	sendAdditionalTelemetryInfo(session: vscode.AuthenticationSession): Promise<void>;
@@ -91,7 +87,7 @@ export class GitHubServer implements IGitHubServer {
 		return this._isNoCorsEnvironment;
 	}
 
-	public async login(scopes: string): Promise<string> {
+	public async login(scopes: string, existingLogin?: string): Promise<string> {
 		this._logger.info(`Logging in for the following scopes: ${scopes}`);
 
 		// Used for showing a friendlier message to the user when the explicitly cancel a flow.
@@ -143,6 +139,7 @@ export class GitHubServer implements IGitHubServer {
 					uriHandler: this._uriHandler,
 					enterpriseUri: this._ghesUri,
 					redirectUri: vscode.Uri.parse(await this.getRedirectEndpoint()),
+					existingLogin
 				});
 			} catch (e) {
 				userCancelled = this.processLoginError(e);