Re: [PATCH] grep: provide a noop --recursive option

[Duy Nguyen <pclouds@gmail.com>]

On Sat, Sep 29, 2018 at 4:58 PM Ævar Arnfjörð Bjarmason
<avarab@gmail.com> wrote:
>
> This --recursive (-r) option does nothing, and is purely here to
> appease people who have "grep -r ..." burned into their muscle memory.

GNU grep -r recurses infinitely but Git grep also has --max-depth. How
do these interact? My knee-jerk reaction is -r equals --max-depth=-1
(i.e. overriding previous --mex-depth options on command line, or from
alias)

> Requested-by: Christoph Berg <myon@debian.org>
> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
> ---
>
> On Sat, Sep 29, 2018 at 4:10 PM Christoph Berg <myon@debian.org> wrote:
> >
> > I often use "grep -r $pattern" to recursively grep a source tree. If
> > that takes too long, I hit ^C and tag "git" in front of the command
> > line and re-run it. git then complains "error: unknown switch `r'"
> > because "git grep" is naturally recursive.
> >
> > Could we have "git grep -r" accept the argument for compatibility?
> > Other important grep switches like "-i" are compatible, adding -r
> > would improve usability.
>
> I don't have an opinion on this either way, it doesn't scratch my
> itch, but hey, why not. Here's a patch to implement it.
>
>  Documentation/git-grep.txt | 6 ++++++
>  builtin/grep.c             | 3 +++
>  t/t7810-grep.sh            | 8 ++++++++
>  3 files changed, 17 insertions(+)
>
> diff --git a/Documentation/git-grep.txt b/Documentation/git-grep.txt
> index a3049af1a3..a1aea8be4e 100644
> --- a/Documentation/git-grep.txt
> +++ b/Documentation/git-grep.txt
> @@ -290,6 +290,12 @@ providing this option will cause it to die.
>         Do not output matched lines; instead, exit with status 0 when
>         there is a match and with non-zero status when there isn't.
>
> +-r::
> +--recursive::
> +       This option does nothing. git-grep is always recursive. This
> +       noop option is provided for compatibility with the muscle
> +       memory of people used to grep(1).
> +
>  <tree>...::
>         Instead of searching tracked files in the working tree, search
>         blobs in the given trees.
> diff --git a/builtin/grep.c b/builtin/grep.c
> index 601f801158..02d4384225 100644
> --- a/builtin/grep.c
> +++ b/builtin/grep.c
> @@ -785,6 +785,7 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
>         int use_index = 1;
>         int pattern_type_arg = GREP_PATTERN_TYPE_UNSPECIFIED;
>         int allow_revs;
> +       int unused_recursive; /* this is never used */
>
>         struct option options[] = {
>                 OPT_BOOL(0, "cached", &cached,
> @@ -802,6 +803,8 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
>                         N_("show non-matching lines")),
>                 OPT_BOOL('i', "ignore-case", &opt.ignore_case,
>                         N_("case insensitive matching")),
> +               OPT_BOOL('r', "recursive", &unused_recursive,
> +                       N_("does nothing, git-grep is always recursive, for grep(1) muscle memory compatibility")),
>                 OPT_BOOL('w', "word-regexp", &opt.word_regexp,
>                         N_("match patterns only at word boundaries")),
>                 OPT_SET_INT('a', "text", &opt.binary,
> diff --git a/t/t7810-grep.sh b/t/t7810-grep.sh
> index be5c1bd553..c48d1fa34b 100755
> --- a/t/t7810-grep.sh
> +++ b/t/t7810-grep.sh
> @@ -469,6 +469,14 @@ do
>                 git grep --count -h -e b $H -- ab >actual &&
>                 test_cmp expected actual
>         '
> +
> +       for flag in '' ' -r' ' --recursive'
> +       do
> +               test_expect_success "grep $flag . (testing that --recursive is a noop)" '
> +                       git grep$flag . >actual &&
> +                       test_line_count = 43 actual
> +       '
> +       done
>  done
>
>  cat >expected <<EOF
> --
> 2.19.0.605.g01d371f741
>


-- 
Duy