diff --git a/app/test/config.test.js b/app/test/config.test.js
index cd1975c..4cea9e7 100644
--- a/app/test/config.test.js
+++ b/app/test/config.test.js
@@ -56,3 +56,17 @@ test('loadConfig 在提供 token 時保留 token 值', () => {
   const cfg = loadConfig({ ...base, GITEA_TOKEN: 'secret' })
   assert.equal(cfg.token, 'secret')
 })
+
+test('loadConfig 在 GITEA_TOKEN 為空字串時視為匿名(token 為 null)', () => {
+  const cfg = loadConfig({ ...base, GITEA_TOKEN: '' })
+  assert.equal(cfg.token, null)
+})
+
+test('loadConfig 接受極短與極長的 GITEA_TOKEN', () => {
+  const short = loadConfig({ ...base, GITEA_TOKEN: 'x' })
+  assert.equal(short.token, 'x')
+
+  const longToken = 'a'.repeat(1000)
+  const long = loadConfig({ ...base, GITEA_TOKEN: longToken })
+  assert.equal(long.token, longToken)
+})
diff --git a/app/test/gitea-client.test.js b/app/test/gitea-client.test.js
index c6b82c7..423ad4b 100644
--- a/app/test/gitea-client.test.js
+++ b/app/test/gitea-client.test.js
@@ -90,6 +90,28 @@ test('fetchAllPages 在回應非 JSON 時丟出例外', async () => {
   )
 })
 
+test('fetchAllPages 在回應為非陣列 JSON 時丟出例外', async () => {
+  globalThis.fetch = async () => jsonResponse({ message: 'error object' })
+  const client = new GiteaClient({})
+  await assert.rejects(
+    () => client.fetchAllPages('https://example.com/api'),
+    /non-array JSON payload/,
+  )
+})
+
+test('fetchAllPages 在 fetch 因逾時拋出 AbortError 時向外拋出', async () => {
+  globalThis.fetch = async () => {
+    const err = new Error('The operation was aborted due to timeout')
+    err.name = 'AbortError'
+    throw err
+  }
+  const client = new GiteaClient({})
+  await assert.rejects(
+    () => client.fetchAllPages('https://example.com/api'),
+    (err) => err.name === 'AbortError',
+  )
+})
+
 test('deleteResource 回傳 HTTP 狀態碼', async () => {
   globalThis.fetch = async (url, opts) => {
     assert.equal(opts.method, 'DELETE')
diff --git a/app/test/logger.test.js b/app/test/logger.test.js
new file mode 100644
index 0000000..edd0bcd
--- /dev/null
+++ b/app/test/logger.test.js
@@ -0,0 +1,35 @@
+import { test, afterEach } from 'node:test'
+import assert from 'node:assert/strict'
+import { failError } from '../logger.js'
+
+const realWrite = process.stderr.write
+
+afterEach(() => {
+  process.stderr.write = realWrite
+})
+
+// 攔截寫入 stderr 的內容
+function captureStderr(fn) {
+  const chunks = []
+  process.stderr.write = (chunk) => {
+    chunks.push(String(chunk))
+    return true
+  }
+  try {
+    fn()
+  } finally {
+    process.stderr.write = realWrite
+  }
+  return chunks.join('')
+}
+
+test('failError 對 Error 物件輸出名稱、訊息與堆疊', () => {
+  const out = captureStderr(() => failError(new TypeError('boom')))
+  assert.match(out, /\[ERR\]  TypeError: boom/)
+  assert.match(out, /at /) // 堆疊內容
+})
+
+test('failError 對非 Error 值輸出其字串形式', () => {
+  const out = captureStderr(() => failError('plain failure'))
+  assert.match(out, /\[ERR\]  plain failure/)
+})