Add tests for find_credentials method

Author: Kevin Burke

tests/test_credentials.py

@@ -0,0 +1,17 @@
+from nose.tools import assert_equal
+
+from twilio.rest import find_credentials
+
+def test_creds_not_found():
+    """ I shouldn't find credentials if they are not there """
+    assert_equal(find_credentials({'foo': 'bar'}), (None, None))
+
+def test_find_creds():
+    """ I should find the credentials if they are there """
+    env = {
+        'TWILIO_ACCOUNT_SID': 'AC123',
+        'foo': 'bar',
+        'TWILIO_AUTH_TOKEN': '456',
+    }
+    assert_equal(find_credentials(env), ('AC123', '456'))
+

twilio/rest/__init__.py

@@ -28,13 +28,16 @@
 from twilio.rest.resources import Usage
 
 
-def find_credentials():
+def find_credentials(environ=None):
     """
     Look in the current environment for Twilio credentials
+
+    :param environ: the environment to check
     """
+    environment = environ or os.environ
     try:
-        account = os.environ["TWILIO_ACCOUNT_SID"]
-        token = os.environ["TWILIO_AUTH_TOKEN"]
+        account = environment["TWILIO_ACCOUNT_SID"]
+        token = environment["TWILIO_AUTH_TOKEN"]
         return account, token
     except KeyError:
         return None, None