Resolving Issue #6: enable environment variable usage.

README.rst

@@ -51,6 +51,15 @@ where ``exclude_dirs.txt`` might look like: ::
     # Comments
     test_dirs/test_not_me
 
+Using Environment Variables
+---------------------------
+
+``--exclude-dir=`` can be set by the environment variables ``NOSE_EXCLUDE_DIRS``.
+Multiple exclude paths may be entered by separating them using a ``;``.
+The environment variable ``NOSE_EXCLUDE_DIRS_FILE`` when set to the path of a
+file-based exclusion list functions as though it were passed in with ``--exclude-dir-file=``.
+
+
 Nose Configuration Files
 ========================
 

nose_exclude.py

@@ -9,9 +9,14 @@ class NoseExclude(Plugin):
     def options(self, parser, env=os.environ):
         """Define the command line options for the plugin."""
         super(NoseExclude, self).options(parser, env)
+        env_dirs = []
+        if 'NOSE_EXCLUDE_DIRS' in env:
+            exclude_dirs = env.get('NOSE_EXCLUDE_DIRS','')
+            env_dirs.extend(exclude_dirs.split(';'))
         parser.add_option(
             "--exclude-dir", action="append",
             dest="exclude_dirs",
+            default=env_dirs,
             help="Directory to exclude from test discovery. \
                 Path can be relative to current working directory \
                 or an absolute path. May be specified multiple \
@@ -20,6 +25,7 @@ class NoseExclude(Plugin):
         parser.add_option(
             "--exclude-dir-file", type="string",
             dest="exclude_dir_file",
+            default=env.get('NOSE_EXCLUDE_DIRS_FILE', False),
             help="A file containing a list of directories to exclude \
                 from test discovery. Paths can be relative to current \
                 working directory or an absolute path. \

tests.py

@@ -59,5 +59,32 @@ class TestNoseExcludeDirs_Relative_Args_Mixed(PluginTester, unittest.TestCase):
     def test_proper_dirs_omitted(self):
         assert "FAILED" not in self.output
 
+class TestNoseExcludeEnvVariables(PluginTester, unittest.TestCase):
+    """Test nose-exclude's use of environment variables"""
+    
+    #args = ['--exclude-dir=test_dirs/test_not_me']
+    activate = "-v"
+    plugins = [NoseExclude()]
+    suitepath = os.path.join(os.getcwd(), 'test_dirs')
+    
+    env = {'NOSE_EXCLUDE_DIRS':'test_dirs/build;test_dirs/test_not_me'}
+
+    def test_proper_dirs_omitted(self):
+        assert "FAILED" not in self.output
+
+class TestNoseExcludeDirsEnvFile(PluginTester, unittest.TestCase):
+    """Test nose-exclude directories using relative paths passed
+    by file specified by environment variable
+    """
+
+    activate = "-v"
+    plugins = [NoseExclude()]
+    env = {'NOSE_EXCLUDE_DIRS_FILE':'test_dirs/exclude_dirs.txt'}
+    suitepath = os.path.join(os.getcwd(), 'test_dirs')
+
+    def test_proper_dirs_omitted(self):
+        assert "FAILED" not in self.output
+
+
 if __name__ == '__main__':
     unittest.main()

tox.ini

@@ -0,0 +1,7 @@
+[tox]
+envlist = py25,py26,py27
+
+[testenv]
+deps=nose
+commands=
+  python setup.py test