Update backend_pdf.py to handle case where rgb is None

Tuan · tacaswell · commit 13917124501b · 2017-07-10T22:42:33.000-05:00
diff --git a/lib/matplotlib/backends/backend_pdf.py b/lib/matplotlib/backends/backend_pdf.py
@@ -1627,11 +1627,11 @@ def check_gc(self, gc, fillcolor=None):
         orig_alphas = getattr(gc, '_effective_alphas', (1.0, 1.0))
 
         if gc._rgb is None:
-            if gc.get_linewidth() != 0:
-                warnings.warn('if rgb is None, ' +
-                              'linewidth should also be 0')
-            # doesn't matter what color here
-            gc._rgb = [1, 0, 0, 1]
+            # it should not matter what color here
+            # since linewidth should be 0
+            # unless affected by global settings in rcParams
+            # hence setting zero alpha just incase
+            gc._rgb = [0, 0, 0, 0]
 
         if gc._forced_alpha:
             gc._effective_alphas = (gc._alpha, gc._alpha)
diff --git a/lib/matplotlib/tests/test_backend_pdf.py b/lib/matplotlib/tests/test_backend_pdf.py
@@ -195,20 +195,16 @@ def psfont(*args, **kwargs):
         fig.savefig(tmpfile, format='pdf')
 
 
-def test_pdf_savefig_when_color_is_none():
-    backup_params = mpl.rcParams.copy()
-    mpl.rcParams.update(mpl.rcParamsDefault)
+@pytest.fixture(scope='function')
+def test_pdf_savefig_when_color_is_none(tempdir_factory):
+    rcParams['_internal.classic_mode'] = False
     plt.subplot()
     plt.axis('off')
     plt.plot(np.sin(np.linspace(-5, 5, 100)), 'v', c='none')
-    try:
-        plt.savefig("figure.pdf", format='pdf')
-    except Exception:
-        pytest.fail("Failed to save pdf")
-    plt.savefig("figure.eps", format='eps')
-    result = compare_images('figure.pdf', 'figure.eps', 0)
+    tmpdir_name = str(np.random.randint(100000, 10000000))
+    actual_image = tempdir_factory.mktemp(tmpdir_name).join('figure.pdf')
+    expected_image = tempdir_factory.mktemp(tmpdir_name).join('figure.eps')
+    plt.savefig(str(actual_image), format='pdf')
+    plt.savefig(str(expected_image), format='eps')
+    result = compare_images(str(actual_image), str(expected_image), 0)
     assert result is None
-    from os import remove
-    remove('figure.eps')
-    remove('figure.pdf')
-    mpl.rcParams.update(backup_params)
