Merged revisions 81471-81472 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

........
  r81471 | victor.stinner | 2010-05-22 15:37:56 +0200 (sam., 22 mai 2010) | 7 lines

  Issue #6268: More bugfixes about BOM, UTF-16 and UTF-32

   * Fix seek() method of codecs.open(), don't write the BOM twice after seek(0)
   * Fix reset() method of codecs, UTF-16, UTF-32 and StreamWriter classes
   * test_codecs: use "w+" mode instead of "wt+". "t" mode is not supported by
     Solaris or Windows, but does it really exist? I found it the in the issue.
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  r81472 | victor.stinner | 2010-05-22 15:44:25 +0200 (sam., 22 mai 2010) | 4 lines

  Fix my last commit (r81471) about codecs

  Rememder: don't touch the code just before a commit
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diff --git a/Lib/test/test_codecs.py b/Lib/test/test_codecs.py
index 6e7afc4..598aaa2 100644
--- a/Lib/test/test_codecs.py
+++ b/Lib/test/test_codecs.py
@@ -1604,8 +1604,8 @@
                  "utf-32-le",
                  "utf-32-be")
         for encoding in tests:
-            with codecs.open('foo', 'w+', encoding=encoding) as f:
-                # Check if the BOM is written only once
+            # Check if the BOM is written only once
+            with codecs.open(support.TESTFN, 'w+', encoding=encoding) as f:
                 f.write(data)
                 f.write(data)
                 f.seek(0)
@@ -1613,6 +1613,42 @@
                 f.seek(0)
                 self.assertEquals(f.read(), data * 2)
 
+            # Check that the BOM is written after a seek(0)
+            with codecs.open(support.TESTFN, 'w+', encoding=encoding) as f:
+                f.write(data[0])
+                self.assertNotEquals(f.tell(), 0)
+                f.seek(0)
+                f.write(data)
+                f.seek(0)
+                self.assertEquals(f.read(), data)
+
+            # (StreamWriter) Check that the BOM is written after a seek(0)
+            with codecs.open(support.TESTFN, 'w+', encoding=encoding) as f:
+                f.writer.write(data[0])
+                self.assertNotEquals(f.writer.tell(), 0)
+                f.writer.seek(0)
+                f.writer.write(data)
+                f.seek(0)
+                self.assertEquals(f.read(), data)
+
+            # Check that the BOM is not written after a seek() at a position
+            # different than the start
+            with codecs.open(support.TESTFN, 'w+', encoding=encoding) as f:
+                f.write(data)
+                f.seek(f.tell())
+                f.write(data)
+                f.seek(0)
+                self.assertEquals(f.read(), data * 2)
+
+            # (StreamWriter) Check that the BOM is not written after a seek()
+            # at a position different than the start
+            with codecs.open(support.TESTFN, 'w+', encoding=encoding) as f:
+                f.writer.write(data)
+                f.writer.seek(f.writer.tell())
+                f.writer.write(data)
+                f.seek(0)
+                self.assertEquals(f.read(), data * 2)
+
 
 def test_main():
     support.run_unittest(