広場投稿追加画面の刷新 (#399) (#413)

Reviewed-on: #413
Co-authored-by: miteruzo <miteruzo@naver.com>
Co-committed-by: miteruzo <miteruzo@naver.com>

frontend/src/lib/postImportStorage.test.ts

@@ -0,0 +1,40 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+
+import {
+    clearPostImportSourceDraft,
+    loadPostImportSourceDraft,
+    savePostImportSourceDraft,
+} from '@/lib/postImportStorage'
+
+describe ('post import source draft storage', () => {
+  beforeEach (() => {
+    sessionStorage.clear ()
+    vi.restoreAllMocks ()
+  })
+
+  it ('round-trips and clears the URL list source draft', () => {
+    expect (savePostImportSourceDraft ('https://example.com')).toBe (true)
+    expect (loadPostImportSourceDraft ()).toEqual ({
+	source: 'https://example.com' })
+
+    clearPostImportSourceDraft ()
+
+    expect (loadPostImportSourceDraft ()).toEqual ({ source: '' })
+  })
+
+  it ('ignores malformed stored drafts', () => {
+    sessionStorage.setItem ('post-import-source-draft', '{')
+
+    expect (loadPostImportSourceDraft ()).toEqual ({ source: '' })
+  })
+
+  it ('reports storage access failures without throwing', () => {
+    const onError = vi.fn ()
+    vi.spyOn (Storage.prototype, 'setItem').mockImplementation (() => {
+      throw new DOMException ('quota')
+    })
+
+    expect (savePostImportSourceDraft ('source', onError)).toBe (false)
+    expect (onError).toHaveBeenCalledWith ('ブラウザへ保存できませんでした．')
+  })
+})