This can be used to print the modification time, like `stat` with some
options.
The reason is that `stat` has caused us a number of portability
headaches:
1. It's not available everywhere by default
2. The versions are quite different
For instance, with GNU stat it's `stat -c '%Y'`, with macOS it's `stat
-f %m`.
So now checking a cache file can be done just with builtins.
- Generally better descriptions,
- uname checks to not complerte unavailable options on
NetBSD, FreeBSD, DragonFly, Solaris, Darwin
- Describe/complete GNU's --time=access,mtime... arg
- Remove -f it is a no-op and not documented.
This is sort of slow because it's called hundreds of times.
We used to have a cache, introduced in ad9b4290e, but it was removed
in fee5a9125a because it had
false-positives.
So what we do, because the issue is that this is called hundreds of
times per-commandline, we cache it keyed on the commandline.
This speeds up `complete -C'git sta'` by a factor of 2.3x.
Commit ad9b4290e optimized git completions by adding a completion that would
run on every completion request, which allows to precompute data used by
other completion entries. Unfortunately, the completion entry is not run
when the commandline contains a flag like `git -C`. If we didn't
already load git.fish, we'd error. Additionally, we got false positive
completions for `git diff -c`.
So this hack was a very bad idea. We should optimize in another way.
git versions that only support porcelain v1 output (like on CentOS 7,
which has 1.8.3) weren't completing files prefixed with : correctly iff
the name after the colon was also a valid relative path.
Fixes the tests on CentOS 7.
Git's pathspec system is kind of annoying:
> A pathspec that begins with a colon : has special meaning. In the short form, the leading colon : is followed by zero or more "magic signature" letters (which optionally is terminated by another colon :), and the remainder is the pattern to match against the path. The "magic signature" consists of ASCII symbols that are neither alphanumeric, glob, regex special characters nor colon. The optional colon that terminates the "magic signature" can be omitted if the pattern begins with a character that does not belong to "magic signature" symbol set and is not a colon.
So if we complete `:/foo`, that "works" because "f" is alphanumeric
and so the "/" is the only magic character here.
If, however the filename starts with a magic character, that's used as
a magic signature.
So we do what the docs say and terminate the magic signature after the
"/" (which means "from the repo root").
Fixes#9004
