Re: [PATCH] Introduce "precious" file concept

>
>
> On Tue, Apr 09 2019, Nguyễn Thái Ngọc Duy wrote:
>
> >  Here's the replacement patch that keeps "git clean" behavior the same
> >  as before and only checks 'precious' attribute when --keep-precous is
> >  specified.
>
> Cool to have the expected interaction with -x. Thanks.
>
> > -'git clean' [-d] [-f] [-i] [-n] [-q] [-e <pattern>] [-x | -X] [--] <path>...
> > +'git clean' [<options>] [-d] [-f] [-i] [-n] [-x | -X] [--] <path>...
>
> For e.g. git-status(1) we just say:
>
>     git status [<options>...] [--] [<pathspec>...]
>
> And for git-add(1) we do:
>
>      git add [--verbose | -v] <very long exhaustive list of options
>                               spanning 4 lines omitted>
>
>
> Seems we should do one or the other here, i.e. either just add
> --keep-precious to the list, or leave it at just:
>
>     git clean [<options>...] [--] [<pathspec>...]
>
> > +This attribute is set on files to indicate that their content is
> > +valuable. Some commands will behave slightly different on precious
> > +files. linkgit:git-clean[1] may leave precious files alone.
>
> As noted upthread I think it's better to start with "clean" and
> "--keep-noclean", we can always alias it to "precious" later without
> squatting on that more general term when we (IMO) don't have the full
> picture yet & know if we even want that...
>
> But anyway, with that out of the way and assuming this is kept-as is
> seems we could document this better if we're going to keep "precious",
> e.g. maybe:
>
>     This attribute is set on files to indicate that they're important
>     while not being tracked. This attribute is experimental and subject
>     to future change as more commands are changed to support it.
>
>     Now it's only supported by linkgit:git-clean[1] which'll skip
>     cleaning files marked ith `precious` when given the
>     `--keep-precious` option. This can be useful in combination with
>     linkgit:gitignore[5] to e.g. mark `*.o` build assets as both ignored
>     and precious.
>
> I.e. say it's still early days, that it's "experimental" (not insisting
> on that phrasing, but somehow signaling to users that if they set this
> now it may do new/unexpected things in the future), and briefly describe
> how it works with "clean" and what the main intended use-case is.
>
> > +test_expect_success 'git clean -xd --keep-precious leaves precious files alone' '
> > +     git init precious &&
> > +     (
> > +             cd precious &&
> > +             test_commit one &&
> > +             cat >.gitignore <<-\EOF &&
> > +             *.o
> > +             *.mak
> > +             EOF
> > +             cat >.gitattributes <<-\EOF &&
> > +             *.mak precious
> > +             .gitattributes precious
> > +             *.precious precious
> > +             EOF
> > +             mkdir sub &&
> > +             touch one.o sub/two.o one.mak sub/two.mak &&
> > +             touch one.untracked two.precious sub/also.precious &&
> > +             git clean -fdx --keep-precious &&
> > +             test_path_is_missing one.o &&
> > +             test_path_is_missing sub/two.o &&
> > +             test_path_is_missing one.untracked &&
> > +             test_path_is_file .gitattributes &&
> > +             test_path_is_file one.mak &&
> > +             test_path_is_file sub/two.mak &&
> > +             test_path_is_file two.precious &&
> > +             test_path_is_file sub/also.precious
> > +     )
> > +'
>
> AFAICT this is the first attribute intended purely to be set on files
> that aren't tracked. I wonder if we should test for setting it on files
> that are tracked, and whether we should e.g. warn about that? Maybe not,
> but just raising it since I don't think it was discussed already...