AI: address review on PR #467

frontend/src/pages/tags/NicoTagListPage.test.tsx

@@ -162,12 +162,13 @@ describe ('NicoTagListPage', () => {
     })
   })
 
-  it ('updates links from a tag card', async () => {
+  it ('saves links after completing the tag at the cursor', async () => {
     api.apiGet
       .mockResolvedValueOnce ({
         tags:  [buildNicoTag ({ id: 7, name: 'nico:source' })],
         count: 1,
       })
+      .mockResolvedValueOnce ([buildTag ({ id: 8, name: '連携先', postCount: 3 })])
       .mockResolvedValueOnce ({
         tags: [
           buildNicoTag ({
@@ -183,8 +184,24 @@ describe ('NicoTagListPage', () => {
     renderPage ()
 
     fireEvent.click (await screen.findByRole ('button', { name: '編集' }))
-    fireEvent.change (screen.getByLabelText ('連携する広場タグ'), {
-      target: { value: '連携先' },
+    const textarea = screen.getByLabelText ('連携する広場タグ')
+    fireEvent.change (textarea, { target: { value: '既存 連携\n後続' } })
+    fireEvent.focus (textarea)
+    fireEvent.select (textarea, {
+	target: { selectionStart: 4, selectionEnd: 4 } })
+
+    await waitFor (() => {
+      expect (api.apiGet).toHaveBeenCalledWith (
+	  '/tags/autocomplete',
+	  { locale: 'ja', params: { q: '連携', nico: '0' },
+	    signal: expect.any (AbortSignal) })
+    })
+    fireEvent.mouseDown (await screen.findByText ('連携先'))
+
+    expect (textarea).toHaveValue ('既存 連携先 \n後続')
+    await waitFor (() => {
+      expect ((textarea as HTMLTextAreaElement).selectionStart).toBe (7)
+      expect ((textarea as HTMLTextAreaElement).selectionEnd).toBe (7)
     })
     fireEvent.click (screen.getByRole ('button', { name: '保存' }))
 
@@ -195,6 +212,8 @@ describe ('NicoTagListPage', () => {
           { locale: 'ja', headers: { 'Content-Type': 'multipart/form-data' } },
       )
     })
+    const payload = api.apiPut.mock.calls[0][1] as FormData
+    expect (payload.get ('tags')).toBe ('既存 連携先 \n後続')
     expect (await screen.findByText ('1 件')).toBeInTheDocument ()
   })