feat: persist window geometry and splitter positions via QSettings

Author: chrisdpurcell

src/views/main_window.py

@@ -16,7 +16,7 @@
 import os
 from typing import TypeVar, cast
 
-from PySide6.QtCore import QDir, QFile, QModelIndex, Qt
+from PySide6.QtCore import QDir, QFile, QModelIndex, QSettings, Qt
 from PySide6.QtGui import QAction, QKeySequence, QShortcut
 from PySide6.QtUiTools import QUiLoader
 from PySide6.QtWidgets import (
@@ -30,6 +30,7 @@
     QMessageBox,
     QPlainTextEdit,
     QPushButton,
+    QSplitter,
     QTabWidget,
     QTreeView,
 )
@@ -76,6 +77,10 @@ def __init__(self, viewmodel: MainViewModel) -> None:
         self._load_ui()
         self._setup_file_tree()
         self._connect_signals()
+        self._load_settings()
+        app = QApplication.instance()
+        if app is not None:
+            app.aboutToQuit.connect(self._save_settings)
 
     def show(self) -> None:
         """Show the main application window."""
@@ -181,6 +186,13 @@ def _load_ui(self) -> None:
         self._cursor_label = QLabel("Ln 1, Col 1 | 0 chars")
         self.ui.statusBar().addPermanentWidget(self._cursor_label)
 
+        self._main_splitter = _require(
+            self.ui.findChild(QSplitter, "mainSplitter"), "mainSplitter"
+        )
+        self._left_splitter = _require(
+            self.ui.findChild(QSplitter, "leftPanelSplitter"), "leftPanelSplitter"
+        )
+
     def _setup_file_tree(self) -> None:
         """Configure QFileSystemModel rooted at the user's home directory."""
         self._fs_model = QFileSystemModel(self.ui)
@@ -411,6 +423,29 @@ def _update_cursor_label(self) -> None:
         chars = self._plain_text_edit.document().characterCount() - 1
         self._cursor_label.setText(f"Ln {line}, Col {col} | {chars:,} chars")
 
+    def _load_settings(self) -> None:
+        """Restore window geometry and splitter positions from QSettings.
+
+        Silent no-op when no settings exist yet (first launch or cleared).
+        """
+        settings = QSettings("TextTools", "TextTools")
+        if geometry := settings.value("window/geometry"):
+            self.ui.restoreGeometry(geometry)
+        if main_state := settings.value("splitter/main"):
+            self._main_splitter.restoreState(main_state)
+        if left_state := settings.value("splitter/left"):
+            self._left_splitter.restoreState(left_state)
+
+    def _save_settings(self) -> None:
+        """Save window geometry and splitter positions to QSettings.
+
+        Connected to QApplication.aboutToQuit in __init__.
+        """
+        settings = QSettings("TextTools", "TextTools")
+        settings.setValue("window/geometry", self.ui.saveGeometry())
+        settings.setValue("splitter/main", self._main_splitter.saveState())
+        settings.setValue("splitter/left", self._left_splitter.saveState())
+
     # ------------------------------------------ ViewModel signal handlers
 
     def _on_document_loaded(self, content: str) -> None:

tests/integration/test_main_window.py

@@ -493,3 +493,36 @@ def test_cancelled_dialog_is_no_op(self, window, monkeypatch):
         window._viewmodel.file_saved.connect(emitted.append)
         window._on_action_save_as()
         assert emitted == []
+
+
+class TestConfigPersistence:
+    def test_save_settings_writes_geometry(self, window, qtbot):
+        """_save_settings must write window/geometry to QSettings."""
+        from PySide6.QtCore import QSettings
+        s = QSettings("TextTools", "TextTools")
+        s.remove("window/geometry")
+        window.ui.show()
+        window._save_settings()
+        s2 = QSettings("TextTools", "TextTools")
+        assert s2.value("window/geometry") is not None
+
+    def test_load_settings_does_not_raise_when_empty(self, window):
+        """_load_settings must not raise when no settings have been saved."""
+        from PySide6.QtCore import QSettings
+        QSettings("TextTools", "TextTools").clear()
+        window._load_settings()  # must not raise
+
+    def test_save_and_restore_geometry(self, window, qtbot):
+        """Geometry saved by _save_settings is restored by _load_settings."""
+        from PySide6.QtCore import QSettings
+        window.ui.show()
+        window.ui.resize(700, 600)
+        qtbot.wait(10)
+        window._save_settings()
+        window.ui.resize(300, 300)
+        qtbot.wait(10)
+        window._load_settings()
+        qtbot.wait(10)
+        size = window.ui.size()
+        assert size.width() == 700
+        assert size.height() == 600