Remove special logic that closes HTTPConnection socket on EPIPE.

http://bugs.python.org/issue5542

If the socket is closed, the client has no chance to read the response
from the server.  EPIPE means that it isn't possible to write more
data from the socket, but not that it is impossible to read.

Also, various formatting changes.

Lib/test/test_httplib.py

@@ -1,3 +1,4 @@
+import errno
 from http import client
 import io
 import socket
@@ -24,6 +25,21 @@ class FakeSocket:
             raise client.UnimplementedFileMode()
         return self.fileclass(self.text)
 
+class EPipeSocket(FakeSocket):
+
+    def __init__(self, text, pipe_trigger):
+        # When sendall() is called with pipe_trigger, raise EPIPE.
+        FakeSocket.__init__(self, text)
+        self.pipe_trigger = pipe_trigger
+
+    def sendall(self, data):
+        if self.pipe_trigger in data:
+            raise socket.error(errno.EPIPE, "gotcha")
+        self.data += data
+
+    def close(self):
+        pass
+
 class NoEOFStringIO(io.BytesIO):
     """Like StringIO, but raises AssertionError on EOF.
 
@@ -213,6 +229,20 @@ class BasicTest(TestCase):
         finally:
             resp.close()
 
+    def test_epipe(self):
+        sock = EPipeSocket(
+            "HTTP/1.0 401 Authorization Required\r\n"
+            "Content-type: text/html\r\n"
+            "WWW-Authenticate: Basic realm=\"example\"\r\n",
+            b"Content-Length")
+        conn = client.HTTPConnection("example.com")
+        conn.sock = sock
+        self.assertRaises(socket.error,
+                          lambda: conn.request("PUT", "/url", "body"))
+        resp = conn.getresponse()
+        self.assertEqual(401, resp.status)
+        self.assertEqual("Basic realm=\"example\"",
+                         resp.getheader("www-authenticate"))
 
 class OfflineTest(TestCase):
     def test_responses(self):
@@ -277,7 +307,7 @@ class RequestBodyTest(TestCase):
 
     def setUp(self):
         self.conn = client.HTTPConnection('example.com')
-        self.sock = FakeSocket("")
+        self.conn.sock = self.sock = FakeSocket("")
         self.conn.sock = self.sock
 
     def get_headers_and_fp(self):