Test is failing because TESTFN contains now non-ASCII characters.

The path is written to stdout using the default stdout encoding on Windows (like cp1252), but test searches the path encoded with UTF-8. This test should fail also on other platforms with non-UTF-8 locale.

The simplest way to "fix" the test is using TESTFN_ASCII instead of TESTFN.

But there is also an issue in the script itself. It fails or produces a mojibake when the filesystem encoding and the stdout encoding do not match. There are similar issues in other scripts which output file names.