Wait until font caches exist before starting tests

Author: mdboom

lib/matplotlib/font_manager.py

@@ -1284,6 +1284,7 @@ def is_opentype_cff_font(filename):
     return False
 
 fontManager = None
+_fmcache = None
 
 # The experimental fontconfig-based backend.
 if USE_FONTCONFIG and sys.platform != 'win32':
@@ -1329,10 +1330,6 @@ def findfont(prop, fontext='ttf'):
             _fmcache = os.path.join(cachedir, 'fontList.py3k.cache')
         else:
             _fmcache = os.path.join(cachedir, 'fontList.cache')
-    else:
-        # Should only happen in a restricted environment (such as Google App
-        # Engine). Deal with this gracefully by not caching fonts.
-        _fmcache = None
 
     fontManager = None
 

tests.py

@@ -5,13 +5,23 @@
 # See http://somethingaboutorange.com/mrl/projects/nose/1.0.0/usage.html
 # for options.
 
+import os
+import time
+
 import matplotlib
 matplotlib.use('agg')
 
 import nose
 from matplotlib.testing.noseclasses import KnownFailure
 from matplotlib import default_test_modules
 
+from matplotlib import font_manager
+# Make sure the font caches are created before starting any possibly
+# parallel tests
+if font_manager._fmcache is not None:
+    while not os.path.exists(font_manager._fmcache):
+        time.sleep(0.5)
+
 def run():
     nose.main(addplugins=[KnownFailure()],
               defaultTest=default_test_modules)