Fixed #107 Explicit error message when WSGIProxy2 is not installer

2 files changed, 10 insertions, 3 deletions

diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 34905ba..e8d8f04 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -4,7 +4,7 @@ News
 2.0.15 (unreleased)
 -------------------
 
-- Nothing changed yet.
+- Fixed #107 Explicit error message when WSGIProxy2 is not installer
 
 
 2.0.14 (2014-01-23)
diff --git a/webtest/app.py b/webtest/app.py
index e58ba46..6acdde1 100644
--- a/webtest/app.py
+++ b/webtest/app.py
@@ -120,7 +120,13 @@ class TestApp(object):
             app = os.environ['WEBTEST_TARGET_URL']
         if isinstance(app, string_types):
             if app.startswith('http'):
-                from wsgiproxy import HostProxy
+                try:
+                    from wsgiproxy import HostProxy
+                except ImportError:
+                    raise ImportError((
+                        'Using webtest with a real url requires WSGIProxy2. '
+                        'Please install it with: '
+                        'pip install WSGIProxy2'))
                 if '#' not in app:
                     app += '#httplib'
                 url, client = app.split('#', 1)
@@ -571,7 +577,8 @@ class TestApp(object):
 
     def _gen_request(self, method, url, params=utils.NoDefault,
                      headers=None, extra_environ=None, status=None,
-                     upload_files=None, expect_errors=False, content_type=None):
+                     upload_files=None, expect_errors=False,
+                     content_type=None):
         """
         Do a generic request.
         """