Various test fixes.

anntzer · anntzer · commit 39df421e871c · 2017-11-17T19:53:11.000-08:00
diff --git a/lib/matplotlib/__init__.py b/lib/matplotlib/__init__.py
@@ -1327,7 +1327,6 @@ def rc_context(rc=None, fname=None):
         dict.update(rcParams, orig)
 
 
-# Could be entirely replaced by pyplot.switch_backends.
 def use(arg, warn=True, force=False):
     """
     Set the Matplotlib backend.
@@ -1340,11 +1339,16 @@ def use(arg, warn=True, force=False):
 
     Parameters
     ----------
-    arg : str or List[str]
-        The name of the backend to use.  If a list of backends, they will be
-        tried in order until one successfully loads.
+    arg : str
+        The name of the backend to use.
     """
-    rcParams["backend"] = arg
+    if not isinstance(arg, six.string_types):
+        # We want to keep 'use(...); rcdefaults()' working, which means that
+        # use(...) needs to force the default backend, and thus be a single
+        # string.
+        raise TypeError("matplotlib.use takes a single string as argument")
+    rcParams["backend"] = \
+        rcParamsDefault["backend"] = rcParamsOrig["backend"] = arg
 
 
 def get_backend():
diff --git a/lib/matplotlib/sphinxext/plot_directive.py b/lib/matplotlib/sphinxext/plot_directive.py
@@ -154,24 +154,16 @@
 import sphinx
 
 sphinx_version = sphinx.__version__.split(".")
-# The split is necessary for sphinx beta versions where the string is
-# '6b1'
+# The split is necessary for sphinx beta versions where the string is '6b1'.
 sphinx_version = tuple([int(re.split('[^0-9]', x)[0])
                         for x in sphinx_version[:2]])
 
 import jinja2  # Sphinx dependency.
 
 import matplotlib
+matplotlib.use("agg")
 import matplotlib.cbook as cbook
-try:
-    with warnings.catch_warnings(record=True):
-        warnings.simplefilter("error", UserWarning)
-        matplotlib.use('Agg')
-except UserWarning:
-    import matplotlib.pyplot as plt
-    plt.switch_backend("Agg")
-else:
-    import matplotlib.pyplot as plt
+import matplotlib.pyplot as plt
 from matplotlib import _pylab_helpers
 
 __version__ = 2
diff --git a/lib/matplotlib/testing/__init__.py b/lib/matplotlib/testing/__init__.py
@@ -2,9 +2,8 @@
                         unicode_literals)
 
 import functools
-import inspect
+import locale
 import warnings
-from contextlib import contextmanager
 
 import matplotlib
 from matplotlib.cbook import iterable
@@ -41,10 +40,6 @@ def set_reproducibility_for_testing():
 def setup():
     # The baseline images are created in this locale, so we should use
     # it during all of the tests.
-    import locale
-    import warnings
-    from matplotlib.backends import backend_agg, backend_pdf, backend_svg
-
     try:
         locale.setlocale(locale.LC_ALL, str('en_US.UTF-8'))
     except locale.Error:
@@ -53,14 +48,12 @@ def setup():
         except locale.Error:
             warnings.warn(
                 "Could not set locale to English/United States. "
-                "Some date-related tests may fail")
-
-    use('Agg', warn=False)  # use Agg backend for these tests
+                "Some date-related tests may fail.")
 
-    # These settings *must* be hardcoded for running the comparison
-    # tests and are not necessarily the default values as specified in
-    # rcsetup.py
+    matplotlib.use("agg")
     rcdefaults()  # Start with all defaults
 
+    # These settings *must* be hardcoded for running the comparison tests and
+    # are not necessarily the default values as specified in rcsetup.py.
     set_font_settings_for_testing()
     set_reproducibility_for_testing()
diff --git a/lib/matplotlib/tests/test_rcparams.py b/lib/matplotlib/tests/test_rcparams.py
@@ -59,11 +59,9 @@ def test_rcparams():
     assert mpl.rcParams['lines.linewidth'] == linewidth
 
     # test rc_file
-    try:
+    with mpl.rc_context():
         mpl.rc_file(fname)
         assert mpl.rcParams['lines.linewidth'] == 33
-    finally:
-        mpl.rcParams['lines.linewidth'] = linewidth
 
 
 def test_RcParams_class():
