Add isArchivedRepo (#122)

index.ts

@@ -1,7 +1,8 @@
 import reservedNames from 'github-reserved-names/reserved-names.json';
 import collect from './collector.js';
 
-const exists = (selector: string) => Boolean(document.querySelector(selector));
+const $ = (selector: string) => document.querySelector(selector);
+const exists = (selector: string) => Boolean($(selector));
 
 const combinedTestOnly = 'combinedTestOnly'; // To be used only to skip tests of combined functions, i.e. isPageA() || isPageB()
 
@@ -349,6 +350,8 @@ export const isEmptyRepoRoot = (): boolean => isRepoHome() && !exists('link[rel=
 
 export const isEmptyRepo = (): boolean => exists('[aria-label="Cannot fork because repository is empty."]');
 
+export const isArchivedRepo = (): boolean => Boolean(isRepo() && $('#repository-container-header .Label')!.textContent!.endsWith('archive'));
+
 export const isBlank = (): boolean => exists('main .blankslate');
 
 export const isRepoTaxonomyConversationList = (url: URL | HTMLAnchorElement | Location = location): boolean => /^labels\/.+|^milestones\/\d+(?!\/edit)/.test(getRepo(url)?.path!);