Patch #1622: Correct interpretation of various ZIP header fields.

Also fixes
- Issue #1526: Allow more than 64k files to be added to Zip64 file.

- Issue #1746: Correct handling of zipfile archive comments (previously
  archives with comments over 4k were flagged as invalid). Allow writing
  Zip files with archives by setting the 'comment' attribute of a ZipFile.

Doc/library/zipfile.rst

@@ -285,7 +285,7 @@ ZipFile Objects
       member of the given :class:`ZipInfo` instance.  By default, the 
       :class:`ZipInfo` constructor sets this member to :const:`ZIP_STORED`.
 
-The following data attribute is also available:
+The following data attributes are also available:
 
 
 .. attribute:: ZipFile.debug
@@ -294,6 +294,12 @@ The following data attribute is also available:
    output) to ``3`` (the most output).  Debugging information is written to
    ``sys.stdout``.
 
+.. attribute:: ZipFile.comment
+
+   The comment text associated with the ZIP file.  If assigning a comment to a 
+   :class:`ZipFile` instance created with mode 'a' or 'w', this should be a 
+   string no longer than 65535 bytes.  Comments longer than this will be 
+   truncated in the written archive when :meth:`ZipFile.close` is called.
 
 .. _pyzipfile-objects:
 

Lib/test/test_zipfile.py

@@ -712,6 +712,54 @@ class OtherTests(unittest.TestCase):
         zipf.writestr("foo.txt\x00qqq", "O, for a Muse of Fire!")
         self.assertEqual(zipf.namelist(), ['foo.txt'])
 
+    def test_StructSizes(self):
+        # check that ZIP internal structure sizes are calculated correctly
+        self.assertEqual(zipfile.sizeEndCentDir, 22)
+        self.assertEqual(zipfile.sizeCentralDir, 46)
+        self.assertEqual(zipfile.sizeEndCentDir64, 56)
+        self.assertEqual(zipfile.sizeEndCentDir64Locator, 20)
+
+    def testComments(self):
+        # This test checks that comments on the archive are handled properly
+
+        # check default comment is empty
+        zipf = zipfile.ZipFile(TESTFN, mode="w")
+        self.assertEqual(zipf.comment, '')
+        zipf.writestr("foo.txt", "O, for a Muse of Fire!")
+        zipf.close()
+        zipfr = zipfile.ZipFile(TESTFN, mode="r")
+        self.assertEqual(zipfr.comment, '')
+        zipfr.close()
+
+        # check a simple short comment
+        comment = 'Bravely taking to his feet, he beat a very brave retreat.'
+        zipf = zipfile.ZipFile(TESTFN, mode="w")
+        zipf.comment = comment
+        zipf.writestr("foo.txt", "O, for a Muse of Fire!")
+        zipf.close()
+        zipfr = zipfile.ZipFile(TESTFN, mode="r")
+        self.assertEqual(zipfr.comment, comment)
+        zipfr.close()
+
+        # check a comment of max length
+        comment2 = ''.join(['%d' % (i**3 % 10) for i in xrange((1 << 16)-1)])
+        zipf = zipfile.ZipFile(TESTFN, mode="w")
+        zipf.comment = comment2
+        zipf.writestr("foo.txt", "O, for a Muse of Fire!")
+        zipf.close()
+        zipfr = zipfile.ZipFile(TESTFN, mode="r")
+        self.assertEqual(zipfr.comment, comment2)
+        zipfr.close()
+
+        # check a comment that is too long is truncated
+        zipf = zipfile.ZipFile(TESTFN, mode="w")
+        zipf.comment = comment2 + 'oops'
+        zipf.writestr("foo.txt", "O, for a Muse of Fire!")
+        zipf.close()
+        zipfr = zipfile.ZipFile(TESTFN, mode="r")
+        self.assertEqual(zipfr.comment, comment2)
+        zipfr.close()
+
     def tearDown(self):
         support.unlink(TESTFN)
         support.unlink(TESTFN2)

Lib/test/test_zipfile64.py

@@ -2,6 +2,7 @@
 # The test_support.requires call is the only reason for keeping this separate
 # from test_zipfile
 from test import test_support
+
 # XXX(nnorwitz): disable this test by looking for extra largfile resource
 # which doesn't exist.  This test takes over 30 minutes to run in general
 # and requires more disk space than most of the buildbots.
@@ -93,8 +94,31 @@ class TestsWithSourceFile(unittest.TestCase):
             if os.path.exists(fname):
                 os.remove(fname)
 
+
+class OtherTests(unittest.TestCase):
+    def testMoreThan64kFiles(self):
+        # This test checks that more than 64k files can be added to an archive,
+        # and that the resulting archive can be read properly by ZipFile
+        zipf = zipfile.ZipFile(TESTFN, mode="w")
+        zipf.debug = 100
+        numfiles = (1 << 16) * 3/2
+        for i in xrange(numfiles):
+            zipf.writestr("foo%08d" % i, "%d" % (i**3 % 57))
+        self.assertEqual(len(zipf.namelist()), numfiles)
+        zipf.close()
+
+        zipf2 = zipfile.ZipFile(TESTFN, mode="r")
+        self.assertEqual(len(zipf2.namelist()), numfiles)
+        for i in xrange(numfiles):
+            self.assertEqual(zipf2.read("foo%08d" % i), "%d" % (i**3 % 57))
+        zipf.close()
+
+    def tearDown(self):
+        test_support.unlink(TESTFN)
+        test_support.unlink(TESTFN2)
+
 def test_main():
-    run_unittest(TestsWithSourceFile)
+    run_unittest(TestsWithSourceFile, OtherTests)
 
 if __name__ == "__main__":
     test_main()

Misc/NEWS

@@ -33,6 +33,14 @@ Core and Builtins
 Library
 -------
 
+- Issue #1622: Correct interpretation of various ZIP header fields.
+
+- Issue #1526: Allow more than 64k files to be added to Zip64 file.
+
+- Issue #1746: Correct handling of zipfile archive comments (previously
+  archives with comments over 4k were flagged as invalid). Allow writing
+  Zip files with archives by setting the 'comment' attribute of a ZipFile.  
+
 - Issue #449227: Now with the rlcompleter module, callable objects are added
   "(" when completed.