Fulfill local branch checking when checkout to an remote branch

extensions/git/src/api/git.d.ts

@@ -26,6 +26,11 @@ export interface Ref {
 	readonly remote?: string;
 }
 
+export interface Trackingship {
+	readonly local: string;
+	readonly upstarem: string;
+}
+
 export interface UpstreamRef {
 	readonly remote: string;
 	readonly name: string;

extensions/git/src/commands.ts

@@ -52,11 +52,20 @@ class CheckoutRemoteHeadItem extends CheckoutItem {
 	}
 
 	async run(repository: Repository): Promise<void> {
-		if (!this.ref.name) {
+		const ref = this.ref.name;
+		if (!ref) {
 			return;
 		}
 
-		await repository.checkoutTracking(this.ref.name);
+		// Check whether there's a local branch which already has the target branch as an upstream
+		const trackings = await repository.getTracking(ref);
+		if (trackings.length > 0) {
+			//Just checkout the local branch
+			await repository.checkout(trackings[0].local);
+		} else {
+			// Default
+			await repository.checkoutTracking(ref);
+		}
 	}
 }
 
@@ -1373,6 +1382,9 @@ export class CommandCenter {
 		const placeHolder = localize('select a ref to checkout', 'Select a ref to checkout');
 		const choice = await window.showQuickPick(picks, { placeHolder });
 
+		// TODO: Judge whether it's local branch
+		console.log(choice);
+
 		if (!choice) {
 			return false;
 		}

extensions/git/src/git.ts

@@ -14,7 +14,7 @@ import * as filetype from 'file-type';
 import { assign, groupBy, denodeify, IDisposable, toDisposable, dispose, mkdirp, readBytes, detectUnicodeEncoding, Encoding, onceEvent } from './util';
 import { CancellationToken } from 'vscode';
 import { detectEncoding } from './encoding';
-import { Ref, RefType, Branch, Remote, GitErrorCodes } from './api/git';
+import { Ref, RefType, Branch, Remote, GitErrorCodes, Trackingship } from './api/git';
 
 const readfile = denodeify<string, string | null, string>(fs.readFile);
 
@@ -1374,6 +1374,21 @@ export class Repository {
 		}
 	}
 
+	async GetTracking(upstreamBranch: string): Promise<Trackingship[]> {
+		const result = await this.run(['for-each-ref', '--format', '%(if)%(upstream:short)%(then)%(refname:short)->%(upstream:short) %(else)*  %(end)', 'refs/heads']);
+		return result.stdout.trim().split('\n')
+			.map(line => line.trim())
+			.filter(line => line !== '*')
+			.map(line => {
+				const splited = line.split('->');
+				return {
+					local: splited[0],
+					upstarem: splited[1]
+				} as Trackingship;
+			})
+			.filter(trackingShip => trackingShip.upstarem === upstreamBranch);
+	}
+
 	async getRefs(): Promise<Ref[]> {
 		const result = await this.run(['for-each-ref', '--format', '%(refname) %(objectname)', '--sort', '-committerdate']);
 

extensions/git/src/repository.ts

@@ -13,7 +13,7 @@ import * as path from 'path';
 import * as nls from 'vscode-nls';
 import * as fs from 'fs';
 import { StatusBarCommands } from './statusbar';
-import { Branch, Ref, Remote, RefType, GitErrorCodes } from './api/git';
+import { Branch, Ref, Remote, RefType, GitErrorCodes, Trackingship } from './api/git';
 
 const timeout = (millis: number) => new Promise(c => setTimeout(c, millis));
 
@@ -311,6 +311,7 @@ export const enum Operation {
 	GetObjectDetails = 'GetObjectDetails',
 	SubmoduleUpdate = 'SubmoduleUpdate',
 	RebaseContinue = 'RebaseContinue',
+	GetTracking = 'GetTracking'
 }
 
 function isReadOnly(operation: Operation): boolean {
@@ -880,6 +881,10 @@ export class Repository implements Disposable {
 		await this.run(Operation.CheckoutTracking, () => this.repository.checkout(treeish, [], { track: true }));
 	}
 
+	async getTracking(treeish: string): Promise<Trackingship[]> {
+		return await this.run(Operation.GetTracking, () => this.repository.GetTracking(treeish));
+	}
+
 	async getCommit(ref: string): Promise<Commit> {
 		return await this.repository.getCommit(ref);
 	}