Added tests for picking on host and parasite axes.

productivememberofsociety666 · productivememberofsociety666 · commit 95c48f171395 · 2015-12-01T00:00:28.000+01:00
diff --git a/lib/mpl_toolkits/tests/test_axes_grid1.py b/lib/mpl_toolkits/tests/test_axes_grid1.py
@@ -5,7 +5,9 @@
 
 import matplotlib
 import matplotlib.pyplot as plt
-from matplotlib.testing.decorators import image_comparison
+from matplotlib.backend_bases import MouseEvent
+from matplotlib.externals.six.moves.queue import Queue
+from matplotlib.testing.decorators import image_comparison, cleanup
 from mpl_toolkits.axes_grid1 import make_axes_locatable, host_subplot
 from itertools import product
 import numpy as np
@@ -82,6 +84,69 @@ def test_twin_axes_empty_and_removed():
             horizontalalignment="center", verticalalignment="center")
     plt.subplots_adjust(wspace=0.5, hspace=1)
 
+
+class TestPickingCallbacksOverlap(object):
+    """Test pick events on normal, host or parasite axes."""
+    # Two rectangles are drawn and "clicked on", a small one and a big one
+    # enclosing the small one. The axis on which they are drawn as well as the
+    # rectangle that is clicked on are varied.
+    # In each case we expect that both rectangles are picked if we click on the
+    # small one and only the big one is picked if we click on the big one.
+    # Also tests picking on normal axes ("gca") as a control.
+    def setUp(self):
+        self.q = Queue()
+        self.big = plt.Rectangle((0.25, 0.25), 0.5, 0.5, picker=5)
+        self.small = plt.Rectangle((0.4, 0.4), 0.2, 0.2, facecolor="r",
+            picker=5)
+        plt.gcf().canvas.mpl_connect('pick_event', self.on_pick)
+    def on_pick(self, event):
+        self.q.put(event)
+    def test_picking_simple(self):
+        # Configurations here are of the form: ( big_on_axes, small_on_axes )
+        for rectangles_on_axes in [ ("gca", "gca"), ("host", "host"),
+            ("host", "parasite"), ("parasite", "host"),
+            ("parasite", "parasite") ]:
+            for click_on in [ "big", "small" ]:
+                yield self.run, rectangles_on_axes, click_on
+    @cleanup
+    def run(self, rectangles_on_axes, click_on):
+        # Axes setup
+        axes = { "gca": None, "host": None, "parasite": None }
+        if "gca" in rectangles_on_axes:
+            axes["gca"] = plt.gca()
+        if "host" in rectangles_on_axes or "parasite" in rectangles_on_axes:
+            axes["host"] = host_subplot(111)
+            axes["parasite"] = axes["host"].twin()
+        # Add rectangles to axes
+        (big_on_axes, small_on_axes) = rectangles_on_axes
+        axes[big_on_axes].add_patch(self.big)
+        axes[small_on_axes].add_patch(self.small)
+        # Simulate picking with click mouse event
+        if click_on == "big":
+            click_axes = axes[big_on_axes]
+            axes_coords = (0.3, 0.3)
+        else:
+            click_axes = axes[small_on_axes]
+            axes_coords = (0.5, 0.5)
+        # In reality, mouse events never happen on parasite axes, only host axes
+        if click_axes is axes["parasite"]:
+            click_axes = axes["host"]
+        (x, y) = click_axes.transAxes.transform(axes_coords)
+        m = MouseEvent("button_press_event", click_axes.figure.canvas, x, y,
+        button=1)
+        click_axes.pick(m)
+        # Wait at most a second for events; actual waiting only happens if
+        # something is wrong and tests fail, this won't slow down normal testing
+        n_events = 2 if click_on == "small" else 1
+        event_rects = []
+        for i in range(n_events):
+            event = self.q.get(True, 0.5)
+            event_rects.append(event.artist)
+        assert self.big in event_rects
+        if click_on == "small":
+            assert self.small in event_rects
+
+
 if __name__ == '__main__':
     import nose
     nose.runmodule(argv=['-s', '--with-doctest'], exit=False)
