Ignore window state requests on a hidden window

cocoa/src/toga_cocoa/window.py

@@ -341,7 +341,10 @@ def hide(self):
         self.native.orderOut(self.native)
 
     def get_visible(self):
-        return bool(self.native.isVisible)
+        return (
+            bool(self.native.isVisible)
+            or self.get_window_state(in_progress_state=True) == WindowState.MINIMIZED
+        )
 
     ######################################################################
     # Window state

core/src/toga/window.py

@@ -478,7 +478,9 @@ def state(self) -> WindowState:
 
     @state.setter
     def state(self, state: WindowState) -> None:
-        if not self.resizable and state in {
+        if not self.visible:
+            raise ValueError("Window state of a hidden window cannot be changed.")
+        elif not self.resizable and state in {
             WindowState.MAXIMIZED,
             WindowState.FULLSCREEN,
             WindowState.PRESENTATION,

core/tests/window/test_window.py

@@ -336,6 +336,7 @@ def test_visibility(window, app):
 )
 def test_window_state(window, initial_state, final_state):
     """A window can have different states."""
+    window.show()
     assert window.state == WindowState.NORMAL
 
     window.state = initial_state
@@ -372,17 +373,44 @@ def test_window_state(window, initial_state, final_state):
 )
 def test_window_state_same_as_current(window, state):
     """Setting window state the same as current is a no-op."""
+    window.show()
+
     window.state = state
     assert window.state == state
 
     # Reset the EventLog to check that the action was not re-performed.
     EventLog.reset()
+    window.show()
 
     window.state = state
     assert window.state == state
     assert_action_not_performed(window, f"set window state to {state}")
 
 
+@pytest.mark.parametrize(
+    "state",
+    [
+        WindowState.NORMAL,
+        WindowState.MINIMIZED,
+        WindowState.MAXIMIZED,
+        WindowState.FULLSCREEN,
+        WindowState.PRESENTATION,
+    ],
+)
+def test_hidden_window_state(state):
+    """Window state of a hidden window cannot be changed."""
+    hidden_window = toga.Window(title="Hidden Window")
+    hidden_window.hide()
+
+    with pytest.raises(
+        ValueError,
+        match="Window state of a hidden window cannot be changed.",
+    ):
+        hidden_window.state = state
+        assert_action_not_performed(hidden_window, f"set window state to {state}")
+    hidden_window.close()
+
+
 @pytest.mark.parametrize(
     "state",
     [
@@ -394,6 +422,8 @@ def test_window_state_same_as_current(window, state):
 def test_non_resizable_window_state(state):
     """Non-resizable window's states other than minimized or normal are no-ops."""
     non_resizable_window = toga.Window(title="Non-Resizable Window", resizable=False)
+    non_resizable_window.show()
+
     with pytest.raises(
         ValueError,
         match=f"A non-resizable window cannot be set to a state of {state}.",