Display linked issues in PR overview sidebar

Adds a "Linked Issues" section to the PR Overview sidebar that lists the
issues a PR closes, using the GraphQL `closingIssuesReferences` field.
The section is read-only since GitHub's API does not expose a mutation
for linking/unlinking issues.

Squashed and rebased onto current main; drops the now-redundant
`parsePullRequestState` helper since main has independently introduced
`stateToStateEnum` for the same dedup, and replaces it with an inline
OPEN/CLOSED mapping in `parseClosingIssuesReferences`.

Co-Authored-By: Alex Ross <38270282+alexr00@users.noreply.github.com>

Author: mohamedamara1

src/github/graphql.ts

@@ -768,6 +768,14 @@ export interface PullRequest extends Issue {
 	suggestedReviewers: SuggestedReviewerResponse[];
 	additions?: number;
 	deletions?: number;
+	closingIssuesReferences?: {
+		nodes: {
+			id: number,
+			title: string,
+			number: number,
+			state: 'CLOSED' | 'OPEN'
+		}[];
+	};
 }
 
 export enum DefaultCommitTitle {

src/github/interface.ts

@@ -223,6 +223,13 @@ export interface Issue {
 	reactions: Reaction[];
 }
 
+export interface IssueReference {
+	id: number;
+	number: number;
+	title: string;
+	state: GithubItemStateEnum;
+}
+
 export interface PullRequest extends Issue {
 	isDraft?: boolean;
 	isRemoteHeadDeleted?: boolean;
@@ -242,6 +249,7 @@ export interface PullRequest extends Issue {
 	mergeCommitMeta?: { title: string, description: string };
 	squashCommitMeta?: { title: string, description: string };
 	suggestedReviewers?: ISuggestedReviewer[];
+	closingIssues?: IssueReference[]
 	hasComments?: boolean;
 	additions?: number;
 	deletions?: number;

src/github/pullRequestModel.ts

@@ -54,6 +54,7 @@ import {
 	IGitTreeItem,
 	IRawFileChange,
 	IRawFileContent,
+	IssueReference,
 	ISuggestedReviewer,
 	ITeam,
 	MergeMethod,
@@ -137,6 +138,7 @@ export class PullRequestModel extends IssueModel<PullRequest> implements IPullRe
 	public conflicts?: string[];
 	public suggestedReviewers?: ISuggestedReviewer[];
 	public hasChangesSinceLastReview?: boolean;
+	public closingIssues: IssueReference[];
 	private _showChangesSinceReview: boolean;
 	private _hasPendingReview: boolean = false;
 	private _onDidChangePendingReviewState: vscode.EventEmitter<boolean> = this._register(new vscode.EventEmitter<boolean>());
@@ -265,7 +267,7 @@ export class PullRequestModel extends IssueModel<PullRequest> implements IPullRe
 		}
 
 		this.suggestedReviewers = item.suggestedReviewers;
-
+		this.closingIssues = item.closingIssues ?? [];
 		if (item.isRemoteHeadDeleted != null) {
 			this.isRemoteHeadDeleted = item.isRemoteHeadDeleted;
 		}

src/github/pullRequestOverview.ts

@@ -458,7 +458,8 @@ export class PullRequestOverviewPanel extends IssueOverviewPanel<PullRequestMode
 				currentUserReviewState: reviewState,
 				revertable: pullRequest.state === GithubItemStateEnum.Merged,
 				isCopilotOnMyBehalf: await isCopilotOnMyBehalf(pullRequest, currentUser, coAuthors),
-				generateDescriptionTitle: this.getGenerateDescriptionTitle()
+				generateDescriptionTitle: this.getGenerateDescriptionTitle(),
+				closingIssues: pullRequest.closingIssues,
 			};
 			this._postMessage({
 				command: 'pr.initialize',

src/github/queries.gql

@@ -224,6 +224,14 @@ fragment PullRequestFragment on PullRequest {
 		mergeCommitMessage
 		mergeCommitTitle
 	}
+	closingIssuesReferences(first: 50) {
+		nodes {
+			id
+			number
+			title
+			state
+		}
+	}
 	merged
 	mergeable
 	mergeQueueEntry {

src/github/utils.ts

@@ -924,6 +924,7 @@ export async function parseGraphQLPullRequest(
 		commentCount: graphQLPullRequest.comments.totalCount,
 		additions: graphQLPullRequest.additions,
 		deletions: graphQLPullRequest.deletions,
+		closingIssues: parseClosingIssuesReferences(graphQLPullRequest.closingIssuesReferences?.nodes),
 	};
 	pr.mergeCommitMeta = parseCommitMeta(graphQLPullRequest.baseRepository.mergeCommitTitle, graphQLPullRequest.baseRepository.mergeCommitMessage, pr);
 	pr.squashCommitMeta = parseCommitMeta(graphQLPullRequest.baseRepository.squashMergeCommitTitle, graphQLPullRequest.baseRepository.squashMergeCommitMessage, pr);
@@ -1068,6 +1069,21 @@ function parseSuggestedReviewers(
 	return ret.sort(loginComparator);
 }
 
+function parseClosingIssuesReferences(
+	closingIssuesReferences: Array<{ id: number, number: number, title: string, state: string }> | undefined
+): Array<{ id: number, number: number, title: string, state: GithubItemStateEnum }> {
+	if (!closingIssuesReferences) {
+		return [];
+	}
+
+	return closingIssuesReferences.map(issue => ({
+		id: issue.id,
+		number: issue.number,
+		title: issue.title,
+		state: issue.state === 'OPEN' ? GithubItemStateEnum.Open : GithubItemStateEnum.Closed,
+	}));
+}
+
 /**
  * Used for case insensitive sort by login
  */

src/github/views.ts

@@ -112,6 +112,7 @@ export interface PullRequest extends Issue {
 	busy?: boolean;
 	loadingCommit?: string;
 	generateDescriptionTitle?: string;
+	closingIssues: Pick<Issue, 'title' | 'number' | 'state'>[];
 }
 
 export interface ProjectItemsReply {

webviews/components/sidebar.tsx

@@ -8,7 +8,7 @@ import { closeIcon, copilotIcon, settingsIcon } from './icon';
 import { Reviewer } from './reviewer';
 import { COPILOT_LOGINS } from '../../src/common/copilot';
 import { gitHubLabelColor } from '../../src/common/utils';
-import { IAccount, IMilestone, IProjectItem, isITeam, reviewerId, reviewerLabel, ReviewState } from '../../src/github/interface';
+import { IAccount, IMilestone, IProjectItem, Issue, isITeam, reviewerId, reviewerLabel, ReviewState } from '../../src/github/interface';
 import { ChangeReviewersReply, PullRequest } from '../../src/github/views';
 import PullRequestContext from '../common/context';
 import { Label } from '../common/label';
@@ -53,7 +53,7 @@ function Section({
 	);
 }
 
-export default function Sidebar({ reviewers, labels, hasWritePermission, isIssue, projectItems: projects, milestone, assignees, canAssignCopilot, canRequestCopilotReview }: PullRequest) {
+export default function Sidebar({ reviewers, labels, closingIssues, hasWritePermission, isIssue, projectItems: projects, milestone, assignees, canAssignCopilot, canRequestCopilotReview }: PullRequest) {
 	const {
 		addReviewers,
 		addReviewerCopilot,
@@ -268,6 +268,26 @@ export default function Sidebar({ reviewers, labels, hasWritePermission, isIssue
 					<div className="section-placeholder">No milestone</div>
 				)}
 			</Section>
+
+			<Section
+				id="closingIssues"
+				title="Linked Issues"
+				hasWritePermission={false}
+			>
+				{closingIssues.length > 0 ? (
+					<div className="p-2">
+						{closingIssues.map(issue => (
+							<div className="section-item reviewer">
+								<div className="avatar-with-author gap-2">
+									<IssueItem key={issue.title} issue={issue} />
+								</div>
+							</div>
+						))}
+					</div>
+				) : (
+					<div className="p-4 text-sm text-gray-500 text-center">None yet</div>
+				)}
+			</Section>
 		</div>
 	);
 }
@@ -577,3 +597,26 @@ function ConvertToDraft() {
 		</div>
 	);
 }
+
+function IssueItem({ issue }: { issue: Pick<Issue, 'title' | 'number' | 'state'> }) {
+	return (
+		<>
+			<IssueStateIcon state={issue.state} />
+			<span className="h2">{issue.title}</span>
+		</>
+	);
+}
+
+function IssueStateIcon({ state }: { state: string }) {
+	const normalizedState = state.toLowerCase().trim();
+
+	switch (normalizedState) {
+		case 'open':
+			return settingsIcon;
+		case 'closed':
+			return closeIcon;
+		default:
+			return closeIcon;
+	}
+}
+

webviews/editorWebview/test/builder/pullRequest.ts

@@ -61,6 +61,7 @@ export const PullRequestBuilder = createBuilderClass<PullRequest>()({
 	hasReviewDraft: { default: false },
 	busy: { default: undefined },
 	lastReviewType: { default: undefined },
+	closingIssues: { default: [] },
 	canAssignCopilot: { default: false },
 	canRequestCopilotReview: { default: false },
 	isCopilotOnMyBehalf: { default: false },