Shared _pending_version

synodic_client/application/update_controller.py

@@ -84,6 +84,7 @@ def __init__(
         self._config = config
         self._is_user_active: Callable[[], bool] = lambda: False
         self._update_task: asyncio.Task[None] | None = None
+        self._pending_version: str | None = None
 
         # Derive auto-apply preference from config
         resolved = self._resolve_config()
@@ -214,8 +215,9 @@ def _do_check(self, *, silent: bool) -> None:
                 self._banner.show_error('Updater is not initialized.')
             return
 
-        # Show checking state in settings
-        self._settings_window.set_checking()
+        # Preserve the restart button when an update is already pending
+        if self._pending_version is None:
+            self._settings_window.set_checking()
 
         self._update_task = asyncio.create_task(self._async_check(silent=silent))
 
@@ -258,8 +260,14 @@ def _on_check_finished(self, result: UpdateInfo | None, *, silent: bool = False)
                 logger.debug('Automatic update check: no update available')
             return
 
-        # Update available — show status and start download
         version = str(result.latest_version)
+
+        # Already downloaded — restore the ready state without re-downloading
+        if version == self._pending_version:
+            self._show_ready(version)
+            return
+
+        # New update available — download it
         self._settings_window.set_update_status(
             f'v{version} available',
             UPDATE_STATUS_AVAILABLE_STYLE,
@@ -307,6 +315,8 @@ def _on_download_finished(self, success: bool, version: str) -> None:
         # Persist the client update timestamp
         update_user_config(last_client_update=datetime.now(UTC).isoformat())
 
+        self._pending_version = version
+
         if self._can_auto_apply():
             # Silently apply and restart — no banner, no user interaction
             logger.info('Auto-applying update v%s', version)
@@ -317,7 +327,10 @@ def _on_download_finished(self, success: bool, version: str) -> None:
             self._apply_update(silent=True)
             return
 
-        # Manual mode (or user is active) — show ready banner and let user choose when to restart
+        self._show_ready(version)
+
+    def _show_ready(self, version: str) -> None:
+        """Present the *ready to restart* state in both UIs."""
         self._banner.show_ready(version)
         self._settings_window.set_update_status(
             f'v{version} ready',
@@ -345,6 +358,7 @@ def _apply_update(self, *, silent: bool = False) -> None:
             return
 
         try:
+            self._pending_version = None
             self._client.apply_update_on_exit(restart=True, silent=silent)
             logger.info('Update scheduled — restarting application')
             self._app.quit()

tests/unit/qt/test_update_controller.py

@@ -228,6 +228,81 @@ def test_download_failure_shows_error() -> None:
         assert banner.state.name == 'ERROR'
         settings.set_update_status.assert_called_with('Download failed', UPDATE_STATUS_ERROR_STYLE)
 
+    @staticmethod
+    def test_download_sets_pending_version() -> None:
+        """A successful download should set _pending_version."""
+        ctrl, app, client, banner, settings = _make_controller(auto_apply=False)
+        ctrl._on_download_finished(True, '2.0.0')
+
+        assert ctrl._pending_version == '2.0.0'
+
+
+# ---------------------------------------------------------------------------
+# Pending version — skip redundant downloads
+# ---------------------------------------------------------------------------
+
+
+class TestPendingVersion:
+    """Verify behaviour when an update is already downloaded and pending."""
+
+    @staticmethod
+    def test_check_skips_download_when_version_already_pending() -> None:
+        """Re-checking the same version should restore ready state, not re-download."""
+        ctrl, _app, _client, banner, settings = _make_controller(auto_apply=False)
+        ctrl._pending_version = '2.0.0'
+
+        result = UpdateInfo(available=True, current_version=Version('1.0.0'), latest_version=Version('2.0.0'))
+
+        with patch.object(ctrl, '_start_download') as mock_dl:
+            ctrl._on_check_finished(result, silent=True)
+
+        mock_dl.assert_not_called()
+        assert banner.state.name == 'READY'
+        settings.show_restart_button.assert_called_once()
+
+    @staticmethod
+    def test_check_downloads_when_newer_version() -> None:
+        """A different version should trigger a fresh download."""
+        ctrl, _app, _client, banner, settings = _make_controller(auto_apply=False)
+        ctrl._pending_version = '1.5.0'
+
+        result = UpdateInfo(available=True, current_version=Version('1.0.0'), latest_version=Version('2.0.0'))
+
+        with patch.object(ctrl, '_start_download') as mock_dl:
+            ctrl._on_check_finished(result, silent=True)
+
+        mock_dl.assert_called_once_with('2.0.0')
+
+    @staticmethod
+    def test_do_check_preserves_settings_ui_when_pending() -> None:
+        """set_checking should NOT be called when an update is already pending."""
+        ctrl, _app, _client, banner, settings = _make_controller()
+        ctrl._pending_version = '2.0.0'
+
+        with patch('asyncio.create_task'):
+            ctrl._do_check(silent=True)
+
+        settings.set_checking.assert_not_called()
+
+    @staticmethod
+    def test_do_check_shows_checking_when_no_pending() -> None:
+        """set_checking should be called when there is no pending update."""
+        ctrl, _app, _client, banner, settings = _make_controller()
+
+        with patch('asyncio.create_task'):
+            ctrl._do_check(silent=True)
+
+        settings.set_checking.assert_called_once()
+
+    @staticmethod
+    def test_apply_clears_pending_version() -> None:
+        """_apply_update should clear _pending_version."""
+        ctrl, app, client, banner, settings = _make_controller()
+        ctrl._pending_version = '2.0.0'
+        ctrl._apply_update()
+
+        assert ctrl._pending_version is None
+
 
 # ---------------------------------------------------------------------------
 # User-active gating