Merge pull request #11408 from anntzer/check_figures_equal

timhoffm · web-flow · commit 3a5d8c2a035a · 2018-06-23T19:52:06.000+02:00
Figure equality-based tests.
diff --git a/lib/matplotlib/testing/decorators.py b/lib/matplotlib/testing/decorators.py
@@ -407,6 +407,46 @@ def image_comparison(baseline_images, extensions=None, tol=0,
             savefig_kwargs=savefig_kwarg, style=style)
 
 
+def check_figures_equal(*, extensions=("png", "pdf", "svg"), tol=0):
+    """
+    Decorator for test cases that generate and compare two figures.
+
+    The decorated function must take two arguments, *fig_test* and *fig_ref*,
+    and draw the test and reference images on them.  After the function
+    returns, the figures are saved and compared.
+
+    Arguments
+    ---------
+    extensions : list, default: ["png", "pdf", "svg"]
+        The extensions to test.
+    tol : float
+        The RMS threshold above which the test is considered failed.
+    """
+
+    def decorator(func):
+        import pytest
+
+        _, result_dir = map(Path, _image_directories(func))
+
+        @pytest.mark.parametrize("ext", extensions)
+        def wrapper(ext):
+            fig_test = plt.figure("test")
+            fig_ref = plt.figure("reference")
+            func(fig_test, fig_ref)
+            test_image_path = str(
+                result_dir / (func.__name__ + "." + ext))
+            ref_image_path = str(
+                result_dir / (func.__name__ + "-expected." + ext))
+            fig_test.savefig(test_image_path)
+            fig_ref.savefig(ref_image_path)
+            _raise_on_image_difference(
+                ref_image_path, test_image_path, tol=tol)
+
+        return wrapper
+
+    return decorator
+
+
 def _image_directories(func):
     """
     Compute the baseline and result image directories for testing *func*.
diff --git a/lib/matplotlib/tests/test_axes.py b/lib/matplotlib/tests/test_axes.py
@@ -14,7 +14,7 @@
 import warnings
 
 import matplotlib
-from matplotlib.testing.decorators import image_comparison
+from matplotlib.testing.decorators import image_comparison, check_figures_equal
 import matplotlib.pyplot as plt
 import matplotlib.markers as mmarkers
 import matplotlib.patches as mpatches
@@ -5702,18 +5702,11 @@ def test_plot_columns_cycle_deprecation():
         plt.plot(np.zeros((2, 2)), np.zeros((2, 3)))
 
 
-def test_markerfacecolor_none_alpha():
-    fig1, ax1 = plt.subplots()
-    ax1.plot(0, "o", mfc="none", alpha=.5)
-    buf1 = io.BytesIO()
-    fig1.savefig(buf1)
-
-    fig2, ax2 = plt.subplots()
-    ax2.plot(0, "o", mfc="w", alpha=.5)
-    buf2 = io.BytesIO()
-    fig2.savefig(buf2)
-
-    assert buf1.getvalue() == buf2.getvalue()
+# pdf and svg tests fail using travis' old versions of gs and inkscape.
+@check_figures_equal(extensions=["png"])
+def test_markerfacecolor_none_alpha(fig_test, fig_ref):
+    fig_test.subplots().plot(0, "o", mfc="none", alpha=.5)
+    fig_ref.subplots().plot(0, "o", mfc="w", alpha=.5)
 
 
 def test_tick_padding_tightbbox():
diff --git a/tools/triage_tests.py b/tools/triage_tests.py
@@ -192,14 +192,22 @@ def set_large_image(self, index):
         self.thumbnails[self.current_thumbnail].setFrameShape(1)
 
     def accept_test(self):
-        self.entries[self.current_entry].accept()
+        entry = self.entries[self.current_entry]
+        if entry.status == 'autogen':
+            print('Cannot accept autogenerated test cases.')
+            return
+        entry.accept()
         self.filelist.currentItem().setText(
             self.entries[self.current_entry].display)
         # Auto-move to the next entry
         self.set_entry(min((self.current_entry + 1), len(self.entries) - 1))
 
     def reject_test(self):
-        self.entries[self.current_entry].reject()
+        entry = self.entries[self.current_entry]
+        if entry.status == 'autogen':
+            print('Cannot reject autogenerated test cases.')
+            return
+        entry.reject()
         self.filelist.currentItem().setText(
             self.entries[self.current_entry].display)
         # Auto-move to the next entry
@@ -261,11 +269,14 @@ def __init__(self, path, root, source):
             ]
         self.thumbnails = [os.path.join(self.dir, x) for x in self.thumbnails]
 
-        self.status = 'unknown'
-
-        if self.same(os.path.join(self.dir, self.generated),
+        if not Path(self.destdir, self.generated).exists():
+            # This case arises from a check_figures_equal test.
+            self.status = 'autogen'
+        elif self.same(os.path.join(self.dir, self.generated),
                      os.path.join(self.destdir, self.generated)):
             self.status = 'accept'
+        else:
+            self.status = 'unknown'
 
     def same(self, a, b):
         """
@@ -297,16 +308,18 @@ def display(self):
         Get the display string for this entry.  This is the text that
         appears in the list widget.
         """
-        status_map = {'unknown': '\N{BALLOT BOX}',
-                      'accept':  '\N{BALLOT BOX WITH CHECK}',
-                      'reject':  '\N{BALLOT BOX WITH X}'}
+        status_map = {
+            'unknown': '\N{BALLOT BOX}',
+            'accept':  '\N{BALLOT BOX WITH CHECK}',
+            'reject':  '\N{BALLOT BOX WITH X}',
+            'autogen': '\N{WHITE SQUARE CONTAINING BLACK SMALL SQUARE}',
+        }
         box = status_map[self.status]
         return '{} {} [{}]'.format(box, self.name, self.extension)
 
     def accept(self):
         """
-        Accept this test by copying the generated result to the
-        source tree.
+        Accept this test by copying the generated result to the source tree.
         """
         a = os.path.join(self.dir, self.generated)
         b = os.path.join(self.destdir, self.generated)
@@ -315,8 +328,7 @@ def accept(self):
 
     def reject(self):
         """
-        Reject this test by copying the expected result to the
-        source tree.
+        Reject this test by copying the expected result to the source tree.
         """
         a = os.path.join(self.dir, self.expected)
         b = os.path.join(self.destdir, self.generated)
