fix v13

internal/db/questions_test.go

@@ -31,6 +31,7 @@ func TestQuestions(t *testing.T) {
 		{"GetByUserID", testQuestionsGetByUserID},
 		{"GetByAskUserID", testQuestionsGetByAskUserID},
 		{"AnswerByID", testQuestionsAnswerByID},
+		{"AnswerByIDPrivate", testQuestionsAnswerByIDPrivate},
 		{"DeleteByID", testQuestionsDeleteByID},
 		{"UpdateCensor", testQuestionsUpdateCensor},
 		{"Count", testQuestionsCount},
@@ -322,6 +323,33 @@ func testQuestionsAnswerByID(t *testing.T, ctx context.Context, db *questions) {
 	})
 }
 
+// testQuestionsAnswerByIDPrivate 覆盖 L2「收窄公开」的写入语义：
+// 回答与 is_private 必须在同一次写入里生效，不能出现「公开 + 已作答」的中间态。
+func testQuestionsAnswerByIDPrivate(t *testing.T, ctx context.Context, db *questions) {
+	t.Run("normal", func(t *testing.T) {
+		_, err := db.Create(ctx, CreateQuestionOptions{
+			FromIP:      "114.5.1.4",
+			UserID:      1,
+			Content:     "Content - 1",
+			AskerUserID: 1,
+		})
+		require.Nil(t, err)
+
+		err = db.AnswerByIDPrivate(ctx, 1, "Answer - 1")
+		require.Nil(t, err)
+
+		got, err := db.GetByID(ctx, 1)
+		require.Nil(t, err)
+		require.Equal(t, "Answer - 1", got.Answer)
+		require.True(t, got.IsPrivate)
+	})
+
+	t.Run("not found", func(t *testing.T) {
+		err := db.AnswerByIDPrivate(ctx, 404, "Answer - 1")
+		require.Equal(t, ErrQuestionNotExist, err)
+	})
+}
+
 func testQuestionsDeleteByID(t *testing.T, ctx context.Context, db *questions) {
 	t.Run("normal", func(t *testing.T) {
 		_, err := db.Create(ctx, CreateQuestionOptions{