Default branch and current branch detector improvements (#6636)

1 files changed, 35 insertions, 25 deletions

diff --git a/source/github-helpers/get-default-branch.ts b/source/github-helpers/get-default-branch.ts
index efbbdd4c..ffb87e23 100644
--- a/source/github-helpers/get-default-branch.ts
+++ b/source/github-helpers/get-default-branch.ts
@@ -1,27 +1,27 @@
 import cache from 'webext-storage-cache';
 import elementReady from 'element-ready';
-import * as pageDetect from 'github-url-detection';
+import {type RepositoryInfo} from 'github-url-detection';
 
 import * as api from './api.js';
 import {getRepo} from './index.js';
 import {branchSelector} from './selectors.js';
 
-const isCurrentRepo = ({nameWithOwner}: pageDetect.RepositoryInfo): boolean => Boolean(getRepo()?.nameWithOwner === nameWithOwner);
+const isCurrentRepo = ({nameWithOwner}: RepositoryInfo): boolean => Boolean(getRepo()?.nameWithOwner === nameWithOwner);
 
-// DO NOT use optional arguments/defaults in "cached functions" because they can't be memoized effectively
-// https://github.com/sindresorhus/eslint-plugin-unicorn/issues/1864
-const _getDefaultBranch = cache.function('default-branch', async (repository: pageDetect.RepositoryInfo): Promise<string> => {
-	// TODO: extract from `ref-selector` if available https://github.com/refined-github/refined-github/issues/6557
-	if (isCurrentRepo(repository) && ['', 'commits'].includes(repository.path)) {
-		// We're on the default branch, so we can extract it from the current page. This usually happens on the pages:
-		// @example /user/repo
-		// @example /user/repo/commits (without further path)
-		const branchPicker = await elementReady(branchSelector);
-		if (branchPicker) {
-			return branchPicker.textContent!.trim();
-		}
+// Do not make this function complicated. We're only optimizing for the repo root.
+async function fromDOM(): Promise<string | undefined> {
+	if (!['', 'commits'].includes(getRepo()!.path)) {
+		return undefined;
 	}
 
+	// We're on the default branch, so we can extract it from the current page. This exclusively happens on the exact pages:
+	// /user/repo
+	// /user/repo/commits (without further path)
+	const branchPicker = await elementReady(branchSelector);
+	return branchPicker!.textContent!.trim();
+}
+
+async function fromAPI(repository: RepositoryInfo): Promise<string> {
 	const response = await api.v4(`
 		repository(owner: "${repository.owner}", name: "${repository.name}") {
 			defaultBranchRef {
@@ -31,16 +31,26 @@ const _getDefaultBranch = cache.function('default-branch', async (repository: pa
 	`);
 
 	return response.repository.defaultBranchRef.name;
-}, {
-	maxAge: {hours: 1},
-	staleWhileRevalidate: {days: 20},
-	cacheKey: ([repository]) => repository.nameWithOwner,
-});
-
-export default async function getDefaultBranch(repository: pageDetect.RepositoryInfo | undefined = getRepo()): Promise<string> {
-	if (!repository) {
-		throw new Error('getDefaultBranch was called on a non-repository page');
-	}
+}
+
+// DO NOT use optional arguments/defaults in "cached functions" because they can't be memoized effectively
+// https://github.com/sindresorhus/eslint-plugin-unicorn/issues/1864
+export const getDefaultBranchOfRepo = cache.function('default-branch',
+	async (repository: RepositoryInfo): Promise<string> => {
+		if (!repository) {
+			throw new Error('getDefaultBranch was called on a non-repository page');
+		}
+
+		// eslint-disable-next-line @typescript-eslint/prefer-nullish-coalescing -- Wrong, the type is `false | undefined`
+		return (isCurrentRepo(repository) && await fromDOM()) || fromAPI(repository);
+	},
+	{
+		maxAge: {hours: 1},
+		staleWhileRevalidate: {days: 20},
+		cacheKey: ([repository]) => repository.nameWithOwner,
+	},
+);
 
-	return _getDefaultBranch(repository);
+export default async function getDefaultBranch(): Promise<string> {
+	return getDefaultBranchOfRepo(getRepo()!);
 }