fixed pdf backend saving and modified pdf to eps blank/nonblank comparison and unit test case

Tuan Dung Tran · Tuan Dung Tran · commit 74f8af2d4204 · 2017-05-27T22:03:32.000+10:00
diff --git a/lib/matplotlib/backends/backend_pdf.py b/lib/matplotlib/backends/backend_pdf.py
@@ -1626,6 +1626,13 @@ 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]
+
         if gc._forced_alpha:
             gc._effective_alphas = (gc._alpha, gc._alpha)
         elif fillcolor is None or len(fillcolor) < 4:
diff --git a/lib/matplotlib/testing/compare.py b/lib/matplotlib/testing/compare.py
@@ -355,8 +355,8 @@ def crop_to_same(actual_path, actual_image, expected_path, expected_image):
     # clip the images to the same size -- this is useful only when
     # comparing eps to pdf
     if actual_path[-7:-4] == 'eps' and expected_path[-7:-4] == 'pdf':
-        aw, ah = actual_image.shape
-        ew, eh = expected_image.shape
+        aw, ah, ad = actual_image.shape
+        ew, eh, ed = expected_image.shape
         actual_image = actual_image[int(aw / 2 - ew / 2):int(
             aw / 2 + ew / 2), int(ah / 2 - eh / 2):int(ah / 2 + eh / 2)]
     return actual_image, expected_image
diff --git a/lib/matplotlib/tests/test_backend_pdf.py b/lib/matplotlib/tests/test_backend_pdf.py
@@ -19,7 +19,9 @@
                                             _determinism_check)
 from matplotlib.testing.decorators import image_comparison
 from matplotlib import dviread
+from matplotlib.testing.compare import compare_images
 
+import matplotlib as mpl
 
 needs_tex = pytest.mark.xfail(
     not checkdep_tex(),
@@ -191,3 +193,22 @@ def psfont(*args, **kwargs):
     ax.text(0.5, 0.5, 'hello')
     with tempfile.TemporaryFile() as tmpfile, pytest.raises(ValueError):
         fig.savefig(tmpfile, format='pdf')
+
+
+def test_pdf_savefig_when_color_is_none():
+    backup_params = mpl.rcParams.copy()
+    mpl.rcParams.update(mpl.rcParamsDefault)
+    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)
+    assert result is None
+    from os import remove
+    remove('figure.eps')
+    remove('figure.pdf')
+    mpl.rcParams.update(backup_params)
