Fix unhandled rejections from "upstream ref ... is not a GitHub repo" (#8730)

* Initial plan

* Fix unhandled rejections when upstream ref is not a GitHub repo

Agent-Logs-Url: https://github.com/microsoft/vscode-pull-request-github/sessions/0f354983-7de0-48fd-83e4-7af7fe874a8d

Co-authored-by: alexr00 <38270282+alexr00@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: alexr00 <38270282+alexr00@users.noreply.github.com>

Author: Copilot

src/lm/pullRequestContextProvider.ts

@@ -6,6 +6,7 @@
 import * as vscode from 'vscode';
 import { GitApiImpl } from '../api/api1';
 import { Disposable } from '../common/lifecycle';
+import Logger from '../common/logger';
 import { onceEvent } from '../common/utils';
 import { issueMarkdown } from '../github/markdownUtils';
 import { PullRequestModel } from '../github/pullRequestModel';
@@ -24,6 +25,8 @@ export namespace PRChatContextItem {
 }
 
 export class WorkspaceContextProvider extends Disposable implements vscode.ChatWorkspaceContextProvider {
+	private static readonly ID = 'WorkspaceContextProvider';
+
 	private readonly _onDidChangeWorkspaceChatContext = this._register(new vscode.EventEmitter<void>());
 	readonly onDidChangeWorkspaceChatContext = this._onDidChangeWorkspaceChatContext.event;
 
@@ -70,7 +73,15 @@ export class WorkspaceContextProvider extends Disposable implements vscode.ChatW
 			if (folderManager.gitHubRepositories.length === 0) {
 				continue;
 			}
-			const defaults = await folderManager.getPullRequestDefaults();
+			let defaults;
+			try {
+				defaults = await folderManager.getPullRequestDefaults();
+			} catch (e) {
+				// The folder may have no upstream, a detached HEAD, or an upstream that is not a GitHub
+				// repository. Skip it instead of letting the rejection escape as an unhandled promise.
+				Logger.debug(`Skipping workspace chat context for folder ${folderManager.repository.rootUri.toString()}: ${e.message ?? e}`, WorkspaceContextProvider.ID);
+				continue;
+			}
 
 			let value = `Repository name: ${defaults.repo}
 Owner: ${defaults.owner}

src/view/treeNodes/categoryNode.ts

@@ -297,7 +297,7 @@ export class CategoryTreeNode extends TreeNode implements vscode.TreeItem {
 				hasMorePages = response.hasMorePages;
 				hasUnsearchedRepositories = response.hasUnsearchedRepositories;
 			} catch (e) {
-				if (this.isCopilot && (e.response.status === 422) && e.message.includes('the users do not exist')) {
+				if (this.isCopilot && (e?.response?.status === 422) && e.message?.includes('the users do not exist')) {
 					// Skip it, it's copilot and the repo doesn't have copilot
 				} else {
 					const error = formatError(e);