Minor fixes and testing

symbolic23 · symbolic23 · commit 0804eeb5b5f3 · 2023-04-29T22:51:32.000-04:00
diff --git a/lib/matplotlib/artist.py b/lib/matplotlib/artist.py
@@ -640,7 +640,7 @@ def set_hover(self, hover):
 
         Parameters
         ----------
-        hover : None or bool
+        hover : None or bool or float or function
             This can be one of the following:
 
             - *None*: Hover is disabled for this artist (default).
@@ -663,6 +663,8 @@ def set_hover(self, hover):
               is over the artist, return *hit=True* and props is a dictionary of
               properties you want added to the HoverEvent attributes.
         """
+        if not self.figure and hover is not None:
+            raise ValueError("Cannot hover without an existing figure")
         self._hover = hover
 
     def get_hover(self):
diff --git a/lib/matplotlib/backends/_backend_tk.py b/lib/matplotlib/backends/_backend_tk.py
@@ -311,17 +311,6 @@ def leave_notify_event(self, event):
                       modifiers=self._mpl_modifiers(event),
                       guiEvent=event)._process()
 
-    def hover_event(self, event):
-        artist = event.artist
-        if not artist.get_hover:
-            thismouse = MouseEvent("motion_hover_event", self,
-                       *self.mouseEventCoords(event),
-                       modifiers=self._mpl_modifiers(),
-                       guiEvent=event)
-            HoverEvent("motion_hover_event", self,
-                                thismouse, artist, None)._process()
-        # make tooltip corresponding to this? this part doesn't exactly work
-
     def button_press_event(self, event, dblclick=False):
         # set focus to the canvas so that it can receive keyboard events
         self._tkcanvas.focus_set()
diff --git a/lib/matplotlib/tests/test_artist.py b/lib/matplotlib/tests/test_artist.py
@@ -325,6 +325,24 @@ def test_set_alpha_for_array():
         art._set_alpha_for_array([0.5, np.nan])
 
 
+def test_set_hover():
+    art = martist.Artist() # blank canvas
+    with pytest.raises(ValueError, match="Cannot hover without an existing figure"):
+        art.set_hover(True)
+    
+    fig, ax = plt.subplots()
+    im = ax.imshow(np.arange(36).reshape(6, 6)) # non-blank canvasses
+    ln, = ax.plot(range(5))
+    im.set_hover(True)
+    assert im.get_hover() == True
+    im.set_hover(1.0)
+    assert ln.get_hover() == 1.0
+    ln.set_hover(art.__str__)
+    assert ln.get_hover() is not None
+
+    im.remove()
+    ln.remove()
+
 def test_callbacks():
     def func(artist):
         func.counter += 1
