The purpose of the test was to check that tarfiles with multiple entries for the same file were handled correctly. Such tarfiles are valid and can be manually produced using the 'r' flag.
TarFile.open(result, 'a') seems like it ought to have the same effect as 'tar -r', but apparently it doesn't, and didn't on Python2.6 either.
However, it turns out we can just do TarFile.add twice to get the desired effect.
The purpose of the test was to check that tarfiles with multiple entries for the same file were handled correctly. Such tarfiles are valid and can be manually produced using the 'r' flag.
TarFile. open(result, 'a') seems like it ought to have the same effect as 'tar -r', but apparently it doesn't, and didn't on Python2.6 either.
However, it turns out we can just do TarFile.add twice to get the desired effect.