Re: [PATCH 1/1] Avoid illegal filenames when building Documentation on NTFS

From: Junio C Hamano <gitster@pobox.com>
Date: Jul 10, 2019, 18:26 UTC
Message-ID: <xmqqef2xu4oz.fsf@gitster-ct.c.googlers.com>
In-Reply-To: <xmqqef2zw9op.fsf@gitster-ct.c.googlers.com>

Junio C Hamano <gitster@pobox.com> writes:

Show 7 quoted lines

>> In addition, your `+` scheme will break on Windows once it uses `git.exe`
>> or any other non-MSYS2 helper...
>
> I am not sure what you mean here.  Is your git.exe disabled not to
> be able to do this: "git.exe add hello+kitty.txt"?  I think that is
> a more grave problem, and not limited to the Makefile in the
> Documentation/ directory.

The reason why I thought it was a more grave problem is because (1) gets 7648757 out of (2), which gets 2297783817 (that is, among the 2.2 billion paths that appear in various GitHub public repositories, a tad short of 8 million paths have '+' somewhere):

    (1) SELECT count(*) FROM `bigquery-public-data.github_repos.files`
        where path like '%+%';

    (2) SELECT count(*) FROM `bigquery-public-data.github_repos.files`;

If you drop the technique MSYS2 borrowed from Cygwin to support these characters NTFS does not like by mapping them to a private page, wouldn't it mean that these projects cannot be used with Git for Windows? Are we going to bug each of these projects to change their pathnames?

If that is not the case, then that's fine.

FWIW, I am OK with moving away from '+' in *our* project; that is easy enough to do, and such a change does not have to make the end result visually less pleasing, as long as we pick a good substitute suffix. Is '~' (or ',') allowed on NTFS, for example? The point of '+' being short, sweet, and easy to spot, I'd rather not to use '.<anyword>' if we can avoid it.

Whatever suffix we choose, we need to be aware that the pattern is not limited to Documentation/ directory, so at least the top level .gitignore and Makefile in various subdirectories need vetting.