Added TestCase arguments to setUpPyfakefs() for convenience

CHANGES.md

@@ -6,6 +6,7 @@ The release versions are PyPi releases.
 #### New Features
   * parameter `patch_path` has been removed from `UnitTest` and `Patcher`, 
     the correct patching of `path` imports is now done automatically
+  * `UnitTest` /`Patcher` arguments can now also be set in `setUpPyfakefs()`
   * added pathlib2 support ([#408](../../issues/408)) ([#422](../../issues/422))
   * added some support for extended filesystem attributes under Linux 
   ([#423](../../issues/423)) 

docs/usage.rst

@@ -92,6 +92,9 @@ Customizing Patcher and TestCase
 Both ``fake_filesystem_unittest.Patcher`` and ``fake_filesystem_unittest.TestCase``
 provide a few additional arguments for fine-tuning. These are only needed if
 patching does not work for some module.
+In case of ``fake_filesystem_unittest.TestCase``, these arguments can either
+ be set in the TestCase instance initialization, or in the call of
+``setUpPyfakefs()``.
 
 .. note:: If you need these arguments in ``PyTest``, you have to
   use ``Patcher`` directly instead of the ``fs`` fixture. Alternatively,

pyfakefs/fake_filesystem_unittest.py

@@ -154,19 +154,35 @@ def __init__(self, methodName='runTest'):
     def fs(self):
         return self._stubber.fs
 
-    def setUpPyfakefs(self):
+    def setUpPyfakefs(self,
+                      additional_skip_names=None,
+                      use_dynamic_patch=None,
+                      modules_to_reload=None,
+                      modules_to_patch=None):
         """Bind the file-related modules to the :py:class:`pyfakefs` fake file
         system instead of the real file system.  Also bind the fake `open()`
         function, and on Python 2, the `file()` function.
 
         Invoke this at the beginning of the `setUp()` method in your unit test
         class.
+        For the arguments, see the `TestCaseMixin` attribute description.
+        If any of the arguments is not None, it overwrites the settings for
+        the current test case. Settings the arguments here may be a more
+        convenient way to adapt the setting than overwriting `__init__()`.
         """
+        if additional_skip_names is None:
+            additional_skip_names = self.additional_skip_names
+        if use_dynamic_patch is None:
+            use_dynamic_patch = self.use_dynamic_patch
+        if modules_to_reload is None:
+            modules_to_reload = self.modules_to_reload
+        if modules_to_patch is None:
+            modules_to_patch = self.modules_to_patch
         self._stubber = Patcher(
-            additional_skip_names=self.additional_skip_names,
-            use_dynamic_patch=self.use_dynamic_patch,
-            modules_to_reload=self.modules_to_reload,
-            modules_to_patch=self.modules_to_patch)
+            additional_skip_names=additional_skip_names,
+            use_dynamic_patch=use_dynamic_patch,
+            modules_to_reload=modules_to_reload,
+            modules_to_patch=modules_to_patch)
 
         self._stubber.setUp()
         self.addCleanup(self._stubber.tearDown)

pyfakefs/tests/fake_filesystem_unittest_test.py

@@ -137,14 +137,23 @@ def test_fakepathlib(self):
             self.assertTrue(self.fs.exists('/fake_file.txt'))
 
 
-class TestImportAsOtherName(fake_filesystem_unittest.TestCase):
-    def __init__(self, methodName='RunTest'):
-        modules_to_load = [pyfakefs.tests.import_as_example]
-        super(TestImportAsOtherName, self).__init__(
-            methodName, modules_to_reload=modules_to_load)
+class TestImportAsOtherNameInit(fake_filesystem_unittest.TestCase):
+    def setUp(self):
+        self.setUpPyfakefs(
+            modules_to_reload=[pyfakefs.tests.import_as_example])
 
+    def test_file_exists(self):
+        file_path = '/foo/bar/baz'
+        self.fs.create_file(file_path)
+        self.assertTrue(self.fs.exists(file_path))
+        self.assertTrue(
+            pyfakefs.tests.import_as_example.check_if_exists(file_path))
+
+
+class TestImportAsOtherNameSetup(fake_filesystem_unittest.TestCase):
     def setUp(self):
-        self.setUpPyfakefs()
+        self.setUpPyfakefs(
+            modules_to_reload=[pyfakefs.tests.import_as_example])
 
     def test_file_exists(self):
         file_path = '/foo/bar/baz'
@@ -180,10 +189,6 @@ class TestPathNotPatchedIfNotOsPath(TestPyfakefsUnittestBase):
        An own path module (in this case an alias to math) can be imported
        and used.
     """
-
-    def __init__(self, methodName='runTest'):
-        super(TestPathNotPatchedIfNotOsPath, self).__init__(methodName)
-
     def test_own_path_module(self):
         self.assertEqual(2, path.floor(2.5))