Create pull request should notify if a pull request is already created (#6806)

Fixes #6132

Author: alexr00

common/views.ts

@@ -121,6 +121,7 @@ export interface CreateParamsNew {
 	validate?: boolean;
 	showTitleValidationError?: boolean;
 	createError?: string;
+	warning?: string;
 
 	autoMergeDefault: boolean;
 	autoMerge?: boolean;

src/github/createPRViewProvider.ts

@@ -33,7 +33,7 @@ import {
 } from './folderRepositoryManager';
 import { GitHubRepository } from './githubRepository';
 import { IAccount, ILabel, IMilestone, IProject, isTeam, ITeam, MergeMethod, RepoAccessAndMergeMethods } from './interface';
-import { BaseBranchMetadata } from './pullRequestGitHelper';
+import { BaseBranchMetadata, PullRequestGitHelper } from './pullRequestGitHelper';
 import { PullRequestModel } from './pullRequestModel';
 import { getDefaultMergeMethod } from './pullRequestOverview';
 import { getAssigneesQuickPickItems, getLabelOptions, getMilestoneFromQuickPick, getProjectFromQuickPick, reviewersQuickPick } from './quickPicks';
@@ -605,7 +605,8 @@ export class CreatePullRequestViewProvider extends BaseCreatePullRequestViewProv
 				baseRemote,
 				baseBranch,
 				compareRemote,
-				compareBranch
+				compareBranch,
+				warning: await this.existingPRMessage(),
 			};
 			// TODO: consider updating title and description
 			return this._postMessage({
@@ -616,19 +617,25 @@ export class CreatePullRequestViewProvider extends BaseCreatePullRequestViewProv
 		}));
 	}
 
+	private async existingPRMessage(): Promise<string | undefined> {
+		const existingPR = await PullRequestGitHelper.getMatchingPullRequestMetadataForBranch(this._folderRepositoryManager.repository, this.model.compareBranch);
+		return existingPR ? vscode.l10n.t('A pull request already exists for this branch.') : '';
+	}
+
 	public async setDefaultCompareBranch(compareBranch: Branch | undefined) {
 		const branchChanged = compareBranch && (compareBranch.name !== this.model.compareBranch);
 		const currentCompareRemote = this._folderRepositoryManager.gitHubRepositories.find(repo => repo.remote.owner === this.model.compareOwner)?.remote.remoteName;
 		const branchRemoteChanged = compareBranch && (compareBranch.upstream?.remote !== currentCompareRemote);
 		if (branchChanged || branchRemoteChanged) {
 			this._defaultCompareBranch = compareBranch!.name!;
 			this.model.setCompareBranch(compareBranch!.name);
-			this.changeBranch(compareBranch!.name!, false).then(titleAndDescription => {
+			this.changeBranch(compareBranch!.name!, false).then(async titleAndDescription => {
 				const params: Partial<CreateParamsNew> = {
 					defaultTitle: titleAndDescription.title,
 					defaultDescription: titleAndDescription.description,
 					compareBranch: compareBranch?.name,
-					defaultCompareBranch: compareBranch?.name
+					defaultCompareBranch: compareBranch?.name,
+					warning: await this.existingPRMessage(),
 				};
 				if (!branchRemoteChanged) {
 					return this._postMessage({

src/github/pullRequestOverview.ts

@@ -29,7 +29,6 @@ import {
 	ReviewState,
 } from './interface';
 import { IssueOverviewPanel } from './issueOverview';
-import { PullRequestGitHelper } from './pullRequestGitHelper';
 import { PullRequestModel } from './pullRequestModel';
 import { PullRequestView } from './pullRequestOverviewCommon';
 import { pickEmail, reviewersQuickPick } from './quickPicks';

webviews/createPullRequestViewNew/app.tsx

@@ -342,6 +342,11 @@ export function main() {
 							{params.createError}
 						</ErrorBoundary>
 					</div>
+					<div className={!!params.warning ? 'wrapper validation-warning' : 'hidden'} aria-live='assertive'>
+						<ErrorBoundary>
+							{params.warning}
+						</ErrorBoundary>
+					</div>
 
 					<div className='group-actions'>
 						<button disabled={isBusy} className='secondary' onClick={() => ctx.cancelCreate()}>

webviews/createPullRequestViewNew/index.css

@@ -162,6 +162,13 @@ textarea {
 	color: var(--vscode-inputValidation-errorForeground);
 }
 
+.validation-warning {
+	padding: 5px;
+	border: 1px solid var(--vscode-inputValidation-warningBorder);
+	background-color: var(--vscode-inputValidation-warningBackground);
+	color: var(--vscode-inputValidation-warningForeground);
+}
+
 .below-input-error {
 	border-top: none !important;
 }