Fix avatar fetch error handling for TLS certificate issues

- Wrap second doFetch() call in try-catch to prevent crashes
- Add proper error logging for avatar fetch failures
- Return undefined gracefully when avatar fetching fails
- Improve user identification in error messages for both accounts and teams
- Add test to verify the fix handles TLS errors correctly

Author: Copilot

src/common/uri.ts

@@ -11,7 +11,7 @@ import fetch from 'cross-fetch';
 import * as vscode from 'vscode';
 import { Repository } from '../api/api';
 import { EXTENSION_ID } from '../constants';
-import { IAccount, ITeam, reviewerId } from '../github/interface';
+import { IAccount, isTeam, ITeam, reviewerId } from '../github/interface';
 import { PullRequestModel } from '../github/pullRequestModel';
 import { GitChangeType } from './file';
 import Logger from './logger';
@@ -308,7 +308,14 @@ export namespace DataUri {
 					await doFetch();
 				} catch (e) {
 					// We retry once.
-					await doFetch();
+					try {
+						await doFetch();
+					} catch (retryError) {
+						// Log the error and return undefined instead of crashing
+						const userIdentifier = isTeam(user) ? `${user.org}/${user.slug}` : user.login || 'unknown';
+						Logger.error(`Failed to fetch avatar after retry for user ${userIdentifier}: ${retryError}`, 'avatarCirclesAsImageDataUris');
+						return undefined;
+					}
 				}
 			}
 			if (!innerImageContents) {

src/test/common/uri.test.ts

@@ -0,0 +1,68 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import { default as assert } from 'assert';
+import * as vscode from 'vscode';
+import { DataUri } from '../../common/uri';
+import { IAccount, AccountType } from '../../github/interface';
+
+describe('DataUri.avatarCirclesAsImageDataUris', () => {
+	let mockContext: vscode.ExtensionContext;
+	let originalFetch: any;
+
+	beforeEach(() => {
+		// Save original fetch
+		originalFetch = global.fetch;
+
+		// Create a mock extension context
+		mockContext = {
+			globalStorageUri: vscode.Uri.file('/tmp/test-storage'),
+		} as any as vscode.ExtensionContext;
+	});
+
+	afterEach(() => {
+		// Restore original fetch
+		global.fetch = originalFetch;
+	});
+
+	it('should handle TLS certificate errors gracefully without crashing', async () => {
+		// Mock user with avatar URL
+		const testUser: IAccount = {
+			login: 'testuser',
+			id: '123',
+			avatarUrl: 'https://avatars.githubusercontent.com/u/123?v=4',
+			url: 'https://github.com/testuser',
+			accountType: AccountType.User
+		};
+
+		// Mock fetch to simulate TLS certificate error
+		global.fetch = () => Promise.reject(
+			new Error('request to https://avatars.githubusercontent.com/u/123?v=4 failed, reason: self signed certificate in certificate chain')
+		);
+
+		// Mock vscode.workspace.fs to simulate cache miss
+		const originalReadFile = vscode.workspace.fs.readFile;
+		const originalWriteFile = vscode.workspace.fs.writeFile;
+		const originalCreateDirectory = vscode.workspace.fs.createDirectory;
+
+		vscode.workspace.fs.readFile = () => Promise.reject(new Error('Cache miss'));
+		vscode.workspace.fs.writeFile = () => Promise.resolve();
+		vscode.workspace.fs.createDirectory = () => Promise.resolve();
+
+		try {
+			// This should not throw an error even with TLS issues
+			const results = await DataUri.avatarCirclesAsImageDataUris(mockContext, [testUser], 20, 20);
+
+			// Should return array with undefined for failed fetches
+			assert.strictEqual(results.length, 1);
+			assert.strictEqual(results[0], undefined);
+		} finally {
+			// Restore original functions
+			vscode.workspace.fs.readFile = originalReadFile;
+			vscode.workspace.fs.writeFile = originalWriteFile;
+			vscode.workspace.fs.createDirectory = originalCreateDirectory;
+		}
+	});
+});