[pypy-commit] pypy default: issue1902: fix a buffer flush thinko that rewound the raw stream twice

[pjenvey]

Author: Philip Jenvey <pjenvey at underboss.org>
Branch: 
Changeset: r74282:60d682352d46
Date: 2014-10-29 12:38 -0700
http://bitbucket.org/pypy/pypy/changeset/60d682352d46/

Log:	issue1902: fix a buffer flush thinko that rewound the raw stream
	twice

diff --git a/pypy/module/_io/interp_bufferedio.py b/pypy/module/_io/interp_bufferedio.py
--- a/pypy/module/_io/interp_bufferedio.py
+++ b/pypy/module/_io/interp_bufferedio.py
@@ -812,11 +812,6 @@
         self._check_closed(space, "flush of closed file")
         with self.lock:
             self._flush_and_rewind_unlocked(space)
-            if self.readable:
-                # Rewind the raw stream so that its position corresponds to
-                # the current logical position.
-                self._raw_seek(space, -self._raw_offset(), 1)
-                self._reader_reset_buf()
 
     def _flush_and_rewind_unlocked(self, space):
         self._writer_flush_unlocked(space)
diff --git a/pypy/module/_io/test/test_io.py b/pypy/module/_io/test/test_io.py
--- a/pypy/module/_io/test/test_io.py
+++ b/pypy/module/_io/test/test_io.py
@@ -352,3 +352,13 @@
                 assert mod == 'io'
             else:
                 assert mod == '_io'
+
+    def test_issue1902(self):
+        import _io
+        with _io.open(self.tmpfile, 'w+b', 4096) as f:
+            f.write(b'\xff' * 13569)
+            f.flush()
+            f.seek(0, 0)
+            f.read(1)
+            f.seek(-1, 1)
+            f.write(b'')