[pypy-commit] pypy use-file-star-for-file: test/fix truncate on win32

[bdkearns]

Author: Brian Kearns <bdkearns at gmail.com>
Branch: use-file-star-for-file
Changeset: r73484:e8ce802885c3
Date: 2014-09-11 14:12 -0700
http://bitbucket.org/pypy/pypy/changeset/e8ce802885c3/

Log:	test/fix truncate on win32

diff --git a/rpython/rlib/rfile.py b/rpython/rlib/rfile.py
--- a/rpython/rlib/rfile.py
+++ b/rpython/rlib/rfile.py
@@ -107,6 +107,7 @@
 c_feof = llexternal('feof', [FILEP], rffi.INT, releasegil=False)
 c_ferror = llexternal('ferror', [FILEP], rffi.INT, releasegil=False)
 c_clearerr = llexternal('clearerr', [FILEP], lltype.Void, releasegil=False)
+
 c_setvbuf = llexternal('setvbuf', [FILEP, rffi.CCHARP, rffi.INT, rffi.SIZE_T],
                        rffi.INT, releasegil=False)
 
@@ -568,13 +569,24 @@
     def truncate(self, arg=-1):
         self._check_closed()
         self._check_writable()
+        pos = intmask(c_ftell(self._ll_file))
+        if pos == -1:
+            c_clearerr(self._ll_file)
+            raise _from_errno(IOError)
         if arg == -1:
-            arg = self.tell()
-        self.flush()
+            arg = pos
+        res = c_fflush(self._ll_file)
+        if res != 0:
+            c_clearerr(self._ll_file)
+            raise _from_errno(IOError)
         res = c_ftruncate(self.fileno(), arg)
         if res != 0:
             c_clearerr(self._ll_file)
             raise _from_errno(IOError)
+        res = c_fseek(self._ll_file, pos, os.SEEK_SET)
+        if res != 0:
+            c_clearerr(self._ll_file)
+            raise _from_errno(IOError)
 
     def flush(self):
         self._check_closed()
diff --git a/rpython/rlib/test/test_rfile.py b/rpython/rlib/test/test_rfile.py
--- a/rpython/rlib/test/test_rfile.py
+++ b/rpython/rlib/test/test_rfile.py
@@ -365,11 +365,14 @@
         def f():
             f = open(fname, "w+b")
             f.write("hello world")
-            f.seek(7)
+            f.seek(6)
+            assert f.read(1) == 'w'
             f.truncate()
+            assert f.read(1) == ''
+            f.write('w')
             f.seek(0)
             data = f.read()
-            assert data == "hello w"
+            assert data == "hello ww"
             f.close()
             f = open(fname)
             try: