fix: fix binding of non ValueWidgets in guiclass (#556)

* fix: fix binding of non ValueWidgets in guiclass

* test: only test ipywidgets on 3.9+

* test: skip ipywidgets when missing

* pin ipython differently

* revert test

* test: update

* test: use stem

* add magic class testing extra

* remove other deps

.github/workflows/test_and_deploy.yml

@@ -101,8 +101,7 @@ jobs:
         run: |
           python -m pip install --upgrade pip
           python -m pip install -e .[testing,pyqt5]
-          pip install numpy superqt vispy pyqtgraph
-          python -m pip install ./magic-class
+          python -m pip install ./magic-class[testing]
 
       - name: Test magicclass
         uses: aganders3/headless-gui@v1

pyproject.toml

@@ -76,7 +76,6 @@ testing = [
     "matplotlib",
     "toolz",
     "ipywidgets",
-    "ipython<8.13; python_version<'3.9'",
     "ipykernel",
     "pydantic",
     "attrs",
@@ -122,7 +121,7 @@ docs = [
     "pint",
     "ipywidgets>=8.0.0",
     "ipykernel",
-    "pyside6==6.4.2",  # 6.4.3 gives segfault for some reason
+    "pyside6==6.4.2",    # 6.4.3 gives segfault for some reason
 ]
 
 [project.urls]

src/magicgui/schema/_guiclass.py

@@ -13,7 +13,7 @@
 from dataclasses import Field, dataclass, field, is_dataclass
 from typing import TYPE_CHECKING, Any, Callable, ClassVar, TypeVar, overload
 
-from psygnal import SignalGroup, evented
+from psygnal import SignalGroup, SignalInstance, evented
 from psygnal import __version__ as psygnal_version
 
 from magicgui.schema._ui_field import build_widget
@@ -264,27 +264,35 @@ def bind_gui_to_instance(
         warnings.simplefilter("ignore", category=RuntimeWarning)
 
         for widget in gui:
+            # would be cleaner to check isinstance(widget, ValueWidget)... but a few
+            # widgets (like FileEdit) are not ValueWidgets, but still have a `changed`
+            # signal and a value method. So for now we just check for the protocol.
+            changed = getattr(widget, "changed", None)
+
             # we skip PushButton here, otherwise we will set the value of the
             # button (a boolean) to some attribute on the instance, which is probably
             # not what we want.
-            if isinstance(widget, ValueWidget) and not isinstance(widget, PushButton):
+            if isinstance(changed, SignalInstance) and not isinstance(
+                widget, PushButton
+            ):
+                name: str = getattr(widget, "name", "")
                 # connect changes in the widget to the instance
-                if hasattr(instance, widget.name):
+                if hasattr(instance, name):
                     try:
-                        widget.changed.connect_setattr(
-                            instance, widget.name, **_IGNORE_REF_ERR  # type: ignore
+                        changed.connect_setattr(
+                            instance, name, **_IGNORE_REF_ERR  # type: ignore
                         )
                     except TypeError:
                         warnings.warn(
-                            f"Could not bind {widget.name} to {instance}. "
+                            f"Could not bind {name} to {instance}. "
                             "This may be because the instance has __slots__ or "
                             "other attribute restrictions. Please update psygnal.",
                             stacklevel=2,
                         )
 
                 # connect changes from the instance to the widget
-                if widget.name in signals:
-                    signals[widget.name].connect_setattr(widget, "value")
+                if name in signals:
+                    signals[name].connect_setattr(widget, "value")
 
 
 def unbind_gui_from_instance(gui: ContainerWidget, instance: Any) -> None:

tests/test_gui_class.py

@@ -146,3 +146,24 @@ def foo(self):
     assert t2.gui.y.value == "baz"
     assert isinstance(t2.gui.foo, PushButton)
     assert t2.foo() == {"x": 3, "y": "baz"}
+
+
+def test_path_update():
+    """One off test for FileEdits... which weren't updating.
+
+    (The deeper issue is that things like FileEdit don't subclass ValueWidget...)
+    """
+
+    from pathlib import Path
+
+    @guiclass
+    class MyGuiClass:
+        a: Path = Path("blabla")
+
+    obj = MyGuiClass()
+    assert obj.gui.a.value.stem == "blabla"
+    assert obj.a.stem == "blabla"
+
+    obj.gui.a.value = "foo"
+    assert obj.gui.a.value.stem == "foo"
+    assert obj.a.stem == "foo"