fix(update): 查不到 GitHub 时不再谎报「已是最新版本」

qoder_proxy.py

@@ -3861,16 +3861,30 @@ def update_plan_info():
     cur = VERSION
     latest = ""
     err = ""
+    lookup_failed = False
     try:
         latest = qoder_updater.latest_release().get("version") or ""
     except Exception as exc:
         err = str(exc)[:160]
+        # GitHub 匿名限流 60 次/小时/IP：本函数每次都实时打 API，403 被吞掉后
+        # 曾被渲染成「当前已是最新版本」（2026-11-11 看板自相矛盾）。
+        # 查不到就回退到 /update/check 的缓存；仍拿不到才标记 lookup_failed。
+        try:
+            cached = check_for_update()
+        except Exception:
+            cached = None
+        if isinstance(cached, dict):
+            latest = str(cached.get("latest") or "").strip().lstrip("vV")
+            err = err or str(cached.get("error") or "")
+        if not latest:
+            lookup_failed = True
     has = bool(latest) and version_tuple(latest) > version_tuple(cur)
     return {
         "ok": True,
         "current": cur,
         "latest": latest,
         "has_update": has,
+        "lookup_failed": lookup_failed,
         "container": qoder_updater._in_container(),
         "disabled": UPDATE_DISABLED,
         "can_apply": bool(has) and not UPDATE_DISABLED,
@@ -11360,7 +11374,11 @@ def do_GET(self):
                 _reasons.append("仅允许在本机打开面板执行"
                                 "（或设置 QD_UPDATE_ALLOW_REMOTE=1）")
             if not _info.get("has_update"):
-                _reasons.append("当前已是最新版本")
+                if _info.get("lookup_failed"):
+                    _reasons.append("无法访问 GitHub（限流或网络不可达），"
+                                    "稍后重试或检查代理")
+                else:
+                    _reasons.append("当前已是最新版本")
             _info["client_is_loopback"] = bool(_loopback)
             _info["can_apply"] = bool(_info.get("can_apply")) and not _reasons
             _info["apply_blocked_reasons"] = _reasons

tests/_test_update_lookup_failed.py

@@ -0,0 +1,69 @@
+# -*- coding: utf-8 -*-
+"""/update/plan：GitHub 查不到 ≠ 当前已是最新版本（本机 2026-11-11 看板矛盾）。
+
+    python tests/_test_update_lookup_failed.py
+"""
+import io
+import os
+import sys
+
+sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
+from _suite_head import *          # noqa: F401,F403
+
+P, A = bootstrap()
+declare_suite(__file__, ["qoder_proxy.py"])
+import qoder_updater as U          # noqa: E402
+
+
+class _RateLimited(object):
+    def __call__(self, req, timeout=None):
+        import urllib.error
+        raise urllib.error.HTTPError("https://api.github.com/", 403,
+                                     "rate limit exceeded", {}, None)
+
+
+_orig_urlopen = P.urllib.request.urlopen
+_orig_latest = U.latest_release
+try:
+    # 1) 完全没有缓存 + API 403：必须报 lookup_failed，不许谎报「已是最新」
+    P._update_cache.update({"at": 0.0, "data": None})
+    P.urllib.request.urlopen = _RateLimited()
+    U.urllib.request.urlopen = _RateLimited()
+    _none = P.update_plan_info()
+
+    # 2) 有成功缓存（面板左边那一列的来源）+ API 403：回退到缓存版本
+    P._update_cache.update({
+        "at": __import__("time").time(),
+        "data": {"ok": True, "current": P.VERSION, "latest": "v99.0.0",
+                 "has_update": True, "url": "", "published_at": "",
+                 "name": "", "checked_at": 0, "error": ""},
+    })
+    _cached = P.update_plan_info()
+finally:
+    P.urllib.request.urlopen = _orig_urlopen
+    U.latest_release = _orig_latest
+
+print("[#本机] 查不到时不谎报「已是最新」")
+check("无缓存 + 403 -> lookup_failed", _none.get("lookup_failed") is True, _none)
+check("无缓存 + 403 -> 不再给出 has_update=False 的假结论",
+      _none.get("has_update") is False and bool(_none.get("error")), _none)
+check("无缓存 + 403 -> latest 为空（不编造版本号）", _none.get("latest") == "", _none)
+
+print("[#本机] 有缓存时回退到缓存版本")
+check("有缓存 + 403 -> lookup_failed=False", _cached.get("lookup_failed") is False, _cached)
+check("有缓存 + 403 -> 沿用缓存的 99.0.0", _cached.get("latest") == "99.0.0", _cached)
+check("有缓存 + 403 -> has_update / can_apply 恢复为真",
+      _cached.get("has_update") is True and _cached.get("can_apply") is True, _cached)
+
+print("[#本机] /update/plan 处理器文案")
+_src = io.open(os.path.join(ROOT, "qoder_proxy.py"), encoding="utf-8").read()
+_i = _src.index('if path == "/update/plan":')
+_seg = _src[_i:_i + 1800]
+check("区分「无法访问 GitHub」与「当前已是最新版本」",
+      "无法访问 GitHub" in _seg and "_info.get(\"lookup_failed\")" in _seg, _seg[:0])
+check("lookup_failed 优先于 has_update 判定",
+      _seg.index("lookup_failed") < _seg.index("当前已是最新版本"))
+check("回退读 check_for_update 缓存",
+      "cached = check_for_update()" in _src)
+
+finish()