Update wsgiref for PEP 3333, and fix errors introduced into the test suite by…

Update wsgiref for PEP 3333, and fix errors introduced into the test suite by converting type() checks to isinstance().
(When WSGI specifies a built-in type, it does NOT mean "this type or a subclass" -- it means 'type(x) is SpecifiedType'.)

Lib/test/test_wsgiref.py

@@ -47,7 +47,7 @@ def hello_app(environ,start_response):
         ('Content-Type','text/plain'),
         ('Date','Mon, 05 Jun 2006 18:49:54 GMT')
     ])
-    return ["Hello, world!"]
+    return [b"Hello, world!"]
 
 def run_amock(app=hello_app, data=b"GET / HTTP/1.0\n\n"):
     server = make_server("", 80, app, MockServer, MockHandler)
@@ -165,7 +165,7 @@ class IntegrationTests(TestCase):
     def test_wsgi_input(self):
         def bad_app(e,s):
             e["wsgi.input"].read()
-            s(b"200 OK", [(b"Content-Type", b"text/plain; charset=utf-8")])
+            s("200 OK", [("Content-Type", "text/plain; charset=utf-8")])
             return [b"data"]
         out, err = run_amock(validator(bad_app))
         self.assertTrue(out.endswith(
@@ -177,8 +177,8 @@ class IntegrationTests(TestCase):
 
     def test_bytes_validation(self):
         def app(e, s):
-            s(b"200 OK", [
-                (b"Content-Type", b"text/plain; charset=utf-8"),
+            s("200 OK", [
+                ("Content-Type", "text/plain; charset=utf-8"),
                 ("Date", "Wed, 24 Dec 2008 13:29:32 GMT"),
                 ])
             return [b"data"]
@@ -420,29 +420,6 @@ class HeaderTests(TestCase):
             '\r\n'
         )
 
-    def testBytes(self):
-        h = Headers([
-            (b"Content-Type", b"text/plain; charset=utf-8"),
-            ])
-        self.assertEqual("text/plain; charset=utf-8", h.get("Content-Type"))
-
-        h[b"Foo"] = bytes(b"bar")
-        self.assertEqual("bar", h.get("Foo"))
-        self.assertEqual("bar", h.get(b"Foo"))
-
-        h.setdefault(b"Bar", b"foo")
-        self.assertEqual("foo", h.get("Bar"))
-        self.assertEqual("foo", h.get(b"Bar"))
-
-        h.add_header(b'content-disposition', b'attachment',
-            filename=b'bud.gif')
-        self.assertEqual('attachment; filename="bud.gif"',
-            h.get("content-disposition"))
-
-        del h['content-disposition']
-        self.assertNotIn(b'content-disposition', h)
-
-
 class ErrorHandler(BaseCGIHandler):
     """Simple handler subclass for testing BaseHandler"""
 
@@ -529,10 +506,10 @@ class HandlerTests(TestCase):
 
         def trivial_app1(e,s):
             s('200 OK',[])
-            return [e['wsgi.url_scheme']]
+            return [e['wsgi.url_scheme'].encode('iso-8859-1')]
 
         def trivial_app2(e,s):
-            s('200 OK',[])(e['wsgi.url_scheme'])
+            s('200 OK',[])(e['wsgi.url_scheme'].encode('iso-8859-1'))
             return []
 
         def trivial_app3(e,s):
@@ -590,13 +567,13 @@ class HandlerTests(TestCase):
             ("Status: %s\r\n"
             "Content-Type: text/plain\r\n"
             "Content-Length: %d\r\n"
-            "\r\n%s" % (h.error_status,len(h.error_body),h.error_body)
-            ).encode("iso-8859-1"))
+            "\r\n" % (h.error_status,len(h.error_body))).encode('iso-8859-1')
+            + h.error_body)
 
         self.assertIn("AssertionError", h.stderr.getvalue())
 
     def testErrorAfterOutput(self):
-        MSG = "Some output has been sent"
+        MSG = b"Some output has been sent"
         def error_app(e,s):
             s("200 OK",[])(MSG)
             raise AssertionError("This should be caught by handler")
@@ -605,7 +582,7 @@ class HandlerTests(TestCase):
         h.run(error_app)
         self.assertEqual(h.stdout.getvalue(),
             ("Status: 200 OK\r\n"
-            "\r\n"+MSG).encode("iso-8859-1"))
+            "\r\n".encode("iso-8859-1")+MSG))
         self.assertIn("AssertionError", h.stderr.getvalue())
 
 
@@ -654,8 +631,8 @@ class HandlerTests(TestCase):
 
     def testBytesData(self):
         def app(e, s):
-            s(b"200 OK", [
-                (b"Content-Type", b"text/plain; charset=utf-8"),
+            s("200 OK", [
+                ("Content-Type", "text/plain; charset=utf-8"),
                 ])
             return [b"data"]
 

Lib/wsgiref/handlers.py

@@ -46,7 +46,7 @@ class BaseHandler:
     traceback_limit = None  # Print entire traceback to self.get_stderr()
     error_status = "500 Internal Server Error"
     error_headers = [('Content-Type','text/plain')]
-    error_body = "A server error occurred.  Please contact the administrator."
+    error_body = b"A server error occurred.  Please contact the administrator."
 
     # State variables (don't mess with these)
     status = result = None
@@ -137,7 +137,7 @@ class BaseHandler:
             self.set_content_length()
 
     def start_response(self, status, headers,exc_info=None):
-        """'start_response()' callable as specified by PEP 333"""
+        """'start_response()' callable as specified by PEP 3333"""
 
         if exc_info:
             try:
@@ -149,49 +149,48 @@ class BaseHandler:
         elif self.headers is not None:
             raise AssertionError("Headers already set!")
 
+        self.status = status
+        self.headers = self.headers_class(headers)
         status = self._convert_string_type(status, "Status")
         assert len(status)>=4,"Status must be at least 4 characters"
         assert int(status[:3]),"Status message must begin w/3-digit code"
         assert status[3]==" ", "Status message must have a space after code"
 
-        str_headers = []
-        for name,val in headers:
-            name = self._convert_string_type(name, "Header name")
-            val = self._convert_string_type(val, "Header value")
-            str_headers.append((name, val))
-            assert not is_hop_by_hop(name),"Hop-by-hop headers not allowed"
+        if __debug__:
+            for name, val in headers:
+                name = self._convert_string_type(name, "Header name")
+                val = self._convert_string_type(val, "Header value")
+                assert not is_hop_by_hop(name),"Hop-by-hop headers not allowed"
 
-        self.status = status
-        self.headers = self.headers_class(str_headers)
         return self.write
 
     def _convert_string_type(self, value, title):
         """Convert/check value type."""
-        if isinstance(value, str):
+        if type(value) is str:
             return value
-        assert isinstance(value, bytes), \
-            "{0} must be a string or bytes object (not {1})".format(title, value)
-        return str(value, "iso-8859-1")
+        raise AssertionError(
+            "{0} must be of type str (got {1})".format(title, repr(value))
+        )
 
     def send_preamble(self):
         """Transmit version/status/date/server, via self._write()"""
         if self.origin_server:
             if self.client_is_modern():
-                self._write('HTTP/%s %s\r\n' % (self.http_version,self.status))
+                self._write(('HTTP/%s %s\r\n' % (self.http_version,self.status)).encode('iso-8859-1'))
                 if 'Date' not in self.headers:
                     self._write(
-                        'Date: %s\r\n' % format_date_time(time.time())
+                        ('Date: %s\r\n' % format_date_time(time.time())).encode('iso-8859-1')
                     )
                 if self.server_software and 'Server' not in self.headers:
-                    self._write('Server: %s\r\n' % self.server_software)
+                    self._write(('Server: %s\r\n' % self.server_software).encode('iso-8859-1'))
         else:
-            self._write('Status: %s\r\n' % self.status)
+            self._write(('Status: %s\r\n' % self.status).encode('iso-8859-1'))
 
     def write(self, data):
-        """'write()' callable as specified by PEP 333"""
+        """'write()' callable as specified by PEP 3333"""
 
-        assert isinstance(data, (str, bytes)), \
-            "write() argument must be a string or bytes"
+        assert type(data) is bytes, \
+            "write() argument must be a bytes instance"
 
         if not self.status:
             raise AssertionError("write() before start_response()")
@@ -256,7 +255,7 @@ class BaseHandler:
         self.headers_sent = True
         if not self.origin_server or self.client_is_modern():
             self.send_preamble()
-            self._write(str(self.headers))
+            self._write(bytes(self.headers))
 
 
     def result_is_file(self):
@@ -376,12 +375,6 @@ class SimpleHandler(BaseHandler):
         self.environ.update(self.base_env)
 
     def _write(self,data):
-        if isinstance(data, str):
-            try:
-                data = data.encode("iso-8859-1")
-            except UnicodeEncodeError:
-                raise ValueError("Unicode data must contain only code points"
-                    " representable in ISO-8859-1 encoding")
         self.stdout.write(data)
 
     def _flush(self):

Lib/wsgiref/headers.py

@@ -30,21 +30,20 @@ class Headers:
     """Manage a collection of HTTP response headers"""
 
     def __init__(self,headers):
-        if not isinstance(headers, list):
+        if type(headers) is not list:
             raise TypeError("Headers must be a list of name/value tuples")
-        self._headers = []
-        for k, v in headers:
-            k = self._convert_string_type(k)
-            v = self._convert_string_type(v)
-            self._headers.append((k, v))
+        self._headers = headers
+        if __debug__:
+            for k, v in headers:
+                self._convert_string_type(k)
+                self._convert_string_type(v)
 
     def _convert_string_type(self, value):
         """Convert/check value type."""
-        if isinstance(value, str):
+        if type(value) is str:
             return value
-        assert isinstance(value, bytes), ("Header names/values must be"
-            " a string or bytes object (not {0})".format(value))
-        return str(value, "iso-8859-1")
+        raise AssertionError("Header names/values must be"
+            " of type str (got {0})".format(repr(value)))
 
     def __len__(self):
         """Return the total number of headers, including duplicates."""
@@ -139,6 +138,9 @@ class Headers:
         suitable for direct HTTP transmission."""
         return '\r\n'.join(["%s: %s" % kv for kv in self._headers]+['',''])
 
+    def __bytes__(self):
+        return str(self).encode('iso-8859-1')
+
     def setdefault(self,name,value):
         """Return first matching header value for 'name', or 'value'
 

Lib/wsgiref/validate.py

@@ -128,11 +128,10 @@ def assert_(cond, *args):
         raise AssertionError(*args)
 
 def check_string_type(value, title):
-    if isinstance(value, str):
+    if type (value) is str:
         return value
-    assert isinstance(value, bytes), \
-        "{0} must be a string or bytes object (not {1})".format(title, value)
-    return str(value, "iso-8859-1")
+    raise AssertionError(
+        "{0} must be of type str (got {1})".format(title, repr(value)))
 
 def validator(application):
 
@@ -197,20 +196,21 @@ class InputWrapper:
     def read(self, *args):
         assert_(len(args) == 1)
         v = self.input.read(*args)
-        assert_(isinstance(v, bytes))
+        assert_(type(v) is bytes)
         return v
 
-    def readline(self):
-        v = self.input.readline()
-        assert_(isinstance(v, bytes))
+    def readline(self, *args):
+        assert_(len(args) <= 1)
+        v = self.input.readline(*args)
+        assert_(type(v) is bytes)
         return v
 
     def readlines(self, *args):
         assert_(len(args) <= 1)
         lines = self.input.readlines(*args)
-        assert_(isinstance(lines, list))
+        assert_(type(lines) is list)
         for line in lines:
-            assert_(isinstance(line, bytes))
+            assert_(type(line) is bytes)
         return lines
 
     def __iter__(self):
@@ -229,7 +229,7 @@ class ErrorWrapper:
         self.errors = wsgi_errors
 
     def write(self, s):
-        assert_(isinstance(s, str))
+        assert_(type(s) is str)
         self.errors.write(s)
 
     def flush(self):
@@ -248,7 +248,7 @@ class WriteWrapper:
         self.writer = wsgi_writer
 
     def __call__(self, s):
-        assert_(isinstance(s, (str, bytes)))
+        assert_(type(s) is bytes)
         self.writer(s)
 
 class PartialIteratorWrapper:
@@ -275,6 +275,8 @@ class IteratorWrapper:
         assert_(not self.closed,
             "Iterator read after closed")
         v = next(self.iterator)
+        if type(v) is not bytes:
+            assert_(False, "Iterator yielded non-bytestring (%r)" % (v,))
         if self.check_start_response is not None:
             assert_(self.check_start_response,
                 "The application returns and we started iterating over its body, but start_response has not yet been called")
@@ -294,7 +296,7 @@ class IteratorWrapper:
             "Iterator garbage collected without being closed")
 
 def check_environ(environ):
-    assert_(isinstance(environ, dict),
+    assert_(type(environ) is dict,
         "Environment is not of the right type: %r (environment: %r)"
         % (type(environ), environ))
 
@@ -321,11 +323,11 @@ def check_environ(environ):
         if '.' in key:
             # Extension, we don't care about its type
             continue
-        assert_(isinstance(environ[key], str),
+        assert_(type(environ[key]) is str,
             "Environmental variable %s is not a string: %r (value: %r)"
             % (key, type(environ[key]), environ[key]))
 
-    assert_(isinstance(environ['wsgi.version'], tuple),
+    assert_(type(environ['wsgi.version']) is tuple,
         "wsgi.version should be a tuple (%r)" % (environ['wsgi.version'],))
     assert_(environ['wsgi.url_scheme'] in ('http', 'https'),
         "wsgi.url_scheme unknown: %r" % environ['wsgi.url_scheme'])
@@ -385,12 +387,12 @@ def check_status(status):
             % status, WSGIWarning)
 
 def check_headers(headers):
-    assert_(isinstance(headers, list),
+    assert_(type(headers) is list,
         "Headers (%r) must be of type list: %r"
         % (headers, type(headers)))
     header_names = {}
     for item in headers:
-        assert_(isinstance(item, tuple),
+        assert_(type(item) is tuple,
             "Individual headers (%r) must be of type tuple: %r"
             % (item, type(item)))
         assert_(len(item) == 2)
@@ -428,14 +430,14 @@ def check_content_type(status, headers):
         assert_(0, "No Content-Type header found in headers (%s)" % headers)
 
 def check_exc_info(exc_info):
-    assert_(exc_info is None or isinstance(exc_info, tuple),
+    assert_(exc_info is None or type(exc_info) is tuple,
         "exc_info (%r) is not a tuple: %r" % (exc_info, type(exc_info)))
     # More exc_info checks?
 
 def check_iterator(iterator):
-    # Technically a string is legal, which is why it's a really bad
+    # Technically a bytestring is legal, which is why it's a really bad
     # idea, because it may cause the response to be returned
     # character-by-character
     assert_(not isinstance(iterator, (str, bytes)),
         "You should not return a string as your application iterator, "
-        "instead return a single-item list containing that string.")
+        "instead return a single-item list containing a bytestring.")