added some assertions

1 files changed, 8 insertions, 0 deletions

diff --git a/wsgitools/adapters.py b/wsgitools/adapters.py
index 9f2ab1c..f575295 100644
--- a/wsgitools/adapters.py
+++ b/wsgitools/adapters.py
@@ -12,7 +12,11 @@ class WSGI2to1Adapter:
         self.app = app
     def __call__(self, environ, start_response):
         """WSGI 1.0 interface"""
+        assert isinstance(environ, dict)
         status, headers, iterable = self.app(environ)
+        assert isinstance(status, str)
+        assert isinstance(headers, list)
+        assert hasattr(iterable, "__iter__")
         start_response(status, headers)
         return iterable
 
@@ -25,14 +29,18 @@ class WSGI1to2Adapter:
         self.app = app
     def __call__(self, environ):
         """some interface that might somewhen be known as WSGI 2.0"""
+        assert isinstance(environ, dict)
         results = [None, None, []]
         def start_response(status, headers, exc_info=None):
+            assert isinstance(status, str)
+            assert isinstance(headers, list)
             results[0] = status
             results[1] = headers
             def write_callable(data):
                 results[2].append(data)
             return write_callable
         iterable = self.app(environ, start_response)
+        assert hasattr(iterable, "__iter__")
         if isinstance(iterable, list):
             # retaining .close attribute this way
             iterable[:0] = results[2]