Issue #20007: HTTPResponse.read(0) no more prematurely closes connection.
Original patch by Simon Sapin.
diff --git a/Lib/httplib.py b/Lib/httplib.py
index 5c919d2..56c3341 100644
--- a/Lib/httplib.py
+++ b/Lib/httplib.py
@@ -565,7 +565,7 @@
         # connection, and the user is reading more bytes than will be provided
         # (for example, reading in 1k chunks)
         s = self.fp.read(amt)
-        if not s:
+        if not s and amt:
             # Ideally, we would raise IncompleteRead if the content-length
             # wasn't satisfied, but it might break compatibility.
             self.close()
diff --git a/Lib/test/test_httplib.py b/Lib/test/test_httplib.py
index 3e81a2c..f11fac3 100644
--- a/Lib/test/test_httplib.py
+++ b/Lib/test/test_httplib.py
@@ -153,6 +153,8 @@
         sock = FakeSocket(body)
         resp = httplib.HTTPResponse(sock)
         resp.begin()
+        self.assertEqual(resp.read(0), '')  # Issue #20007
+        self.assertFalse(resp.isclosed())
         self.assertEqual(resp.read(), 'Text')
         self.assertTrue(resp.isclosed())