test(ai-review): 補非整數 idx、空 apiKeys 與 limit 為 0 的邊界測試

app/usage.test.js

@@ -123,6 +123,14 @@ describe('fetchAccountQuota', () => {
     assert.equal(q.available, false);
     assert.match(q.reason, /未支援/);
   });
+
+  it('degrades gracefully when apiKeys is empty or undefined', async () => {
+    const get = async () => { throw new Error('should not be called'); };
+    // 空陣列 / 未提供 key 都不應丟錯，依平台回報無法取得或不適用
+    assert.equal((await fetchAccountQuota('openai', { apiKeys: [], baseURL: 'https://api.openai.com/v1' }, { get })).available, false);
+    assert.equal((await fetchAccountQuota('ollama', { apiKeys: [] }, { get })).available, false);
+    assert.equal((await fetchAccountQuota('claude', {}, { get })).available, false);
+  });
 });
 
 describe('recordRateLimit / getRateLimit', () => {
@@ -178,6 +186,12 @@ describe('resolveRemainingPercent', () => {
     assert.equal(pct.percent, null);
     assert.match(pct.reason, /無上限/);
   });
+
+  it('does not divide by zero when quota.limit is 0', () => {
+    const pct = resolveRemainingPercent({ available: true, used: 5, limit: 0, currency: 'USD' }, { hasData: false });
+    assert.equal(pct.percent, null); // limit > 0 守衛擋掉除以零
+    assert.ok(typeof pct.reason === 'string' && pct.reason.length > 0);
+  });
 });
 
 describe('formatUsageStats', () => {