Increase default tolerance slightly for 32-bit systems.

QuLogic · QuLogic · commit e7dfc22379e2 · 2020-07-09T04:06:16.000-04:00
Around 900 tests fail on 32-bit systems, but with rather small RMS.
diff --git a/lib/matplotlib/testing/decorators.py b/lib/matplotlib/testing/decorators.py
@@ -336,6 +336,9 @@ def image_comparison(baseline_images, extensions=None, tol=0,
     tol : float, default: 0
         The RMS threshold above which the test is considered failed.
 
+        Due to expected small differences in floating-point calculations, on
+        32-bit systems an additional 0.06 is added to this threshold.
+
     freetype_version : str or tuple
         The expected freetype version or range of versions for this test to
         pass.
@@ -378,6 +381,8 @@ def image_comparison(baseline_images, extensions=None, tol=0,
         extensions = ['png', 'pdf', 'svg']
     if savefig_kwarg is None:
         savefig_kwarg = dict()  # default no kwargs to savefig
+    if sys.maxsize <= 2**32:
+        tol += 0.06
     return _pytest_image_comparison(
         baseline_images=baseline_images, extensions=extensions, tol=tol,
         freetype_version=freetype_version, remove_text=remove_text,
