fix(#4085): align dirty display probes

api/updates.py

@@ -431,21 +431,15 @@ def _dirty_suffix(path: Path, timeout=1) -> str:
     out, ok = _run_git(['diff-index', '--quiet', 'HEAD', '--'], path, timeout=timeout)
     if ok:
         return ""
-    # diff-index --quiet exits 1 with no stdout/stderr to *signal* a dirty tree
-    # (not an error). _run_git() substitutes a synthetic "git exited with
-    # status N" diagnostic when both streams are empty, which makes the naive
-    # `if not out` guard always false on dirty trees — silently dropping the
-    # suffix and defeating dev-build cache busting (static/foo.js?v=… stays
-    # identical to the last-committed version). Treat the synthetic shape as
-    # the dirty signal; real errors (timeouts, missing git) carry a different
-    # diagnostic and correctly suppress the suffix.
-    if not out or out.startswith('git exited with status '):
-        diff, diff_ok = _run_git(['diff', '--binary', 'HEAD', '--'], path, timeout=timeout)
-        if diff_ok and diff:
-            digest = hashlib.sha1(diff.encode('utf-8', errors='replace')).hexdigest()[:8]
-            return f"-dirty-{digest}"
-        return "-dirty"
-    return ""
+    # Only diff-index status 1 means dirty. Keep version display consistent
+    # with the strict action-time probe; all other failures suppress the suffix.
+    if out != 'git exited with status 1':
+        return ""
+    diff, diff_ok = _run_git(['diff', '--binary', 'HEAD', '--'], path, timeout=timeout)
+    if diff_ok and diff:
+        digest = hashlib.sha1(diff.encode('utf-8', errors='replace')).hexdigest()[:8]
+        return f"-dirty-{digest}"
+    return "-dirty"
 
 
 def _describe_git_version(path: Path, *, timeout=5, dirty_timeout=1) -> str | None:
@@ -1943,16 +1937,15 @@ def _discard_local_changes(path: Path, reset_ref: str) -> bool:
 
 
 def apply_force_update(target: str, channel=None) -> dict:
-    """Force-reset the target repo to the latest remote HEAD.
+    """Discard local changes for the requested update target.
 
     Unlike apply_update() which requires a clean working tree and refuses
     merge conflicts, this discards all local modifications (checkout .) and
-    resets to origin/<branch> — equivalent to what the diverged/conflict
-    error messages ask the user to run manually.
+    resets to the selected update ref. A dirty stable WebUI checkout with no
+    promoted ref resets to its symbolic HEAD so the commit itself is unchanged.
 
-    Should only be called when apply_update() has already returned a
-    response with ``conflict: True`` or ``diverged: True`` and the user
-    has confirmed they want to discard local changes.
+    The endpoint is called after the user has confirmed they want to discard
+    local changes, including the stable no-ref dirty-checkout recovery path.
 
     CHANNEL SAFETY (rewind guard): ``reset --hard`` is destructive. When the
     selected channel resolves to a ref that is an ANCESTOR of HEAD (i.e. the

tests/test_updates.py

@@ -813,6 +813,48 @@ def test_run_git_handles_missing_stdout_after_decode_thread_failure(tmp_path):
     assert out == ''
 
 
+@pytest.mark.parametrize('probe_output', [
+    'git exited with status 2',
+    'git exited with status 128',
+    'git exited with status -9',
+])
+def test_describe_git_version_suppresses_unknown_dirty_probe_status(
+    tmp_path, monkeypatch, probe_output,
+):
+    calls = []
+
+    def fake_git(args, cwd, timeout=10):
+        calls.append(args)
+        if args == ['describe', '--tags', '--always']:
+            return 'v0.52.5', True
+        if args == ['diff-index', '--quiet', 'HEAD', '--']:
+            return probe_output, False
+        raise AssertionError(f'unexpected git args: {args!r}')
+
+    monkeypatch.setattr(updates, '_run_git', fake_git)
+
+    assert updates._describe_git_version(tmp_path) == 'v0.52.5'
+    assert calls == [
+        ['describe', '--tags', '--always'],
+        ['diff-index', '--quiet', 'HEAD', '--'],
+    ]
+
+
+def test_describe_git_version_marks_exact_dirty_probe_status(tmp_path, monkeypatch):
+    def fake_git(args, cwd, timeout=10):
+        if args == ['describe', '--tags', '--always']:
+            return 'v0.52.5', True
+        if args == ['diff-index', '--quiet', 'HEAD', '--']:
+            return 'git exited with status 1', False
+        if args == ['diff', '--binary', 'HEAD', '--']:
+            return 'diff --git a/tracked.txt b/tracked.txt', True
+        raise AssertionError(f'unexpected git args: {args!r}')
+
+    monkeypatch.setattr(updates, '_run_git', fake_git)
+
+    assert updates._describe_git_version(tmp_path).startswith('v0.52.5-dirty-')
+
+
 def test_split_remote_ref_splits_tracking_ref():
     """_split_remote_ref should correctly split origin/branch."""
     assert updates._split_remote_ref('origin/master') == ('origin', 'master')