Re: git-prompt.sh incompatible with non-basic global grep.patternType

> Subject: [PATCH] grep: further simplify setting the pattern type
>
> When c5c31d33 (grep: move pattern-type bits support to top-level
> grep.[ch], 2012-10-03) introduced grep_commit_pattern_type() helper
> function, the intention was to allow the users of grep API to having
> to fiddle only with .pattern_type_option (which can be set to "fixed",
> "basic", "extended", and "pcre"), and then immediately before compiling
> the pattern strings for use, call grep_commit_pattern_type() to have
> it prepare various bits in the grep_opt structure (like .fixed,
> .regflags, etc.).
>
> However, grep_set_pattern_type_option() helper function the grep API
> internally uses were left as an external function by mistake.  This
> function shouldn't have been made callable by the users of the API.
>
> Later when the grep API was used in revision graversal machinery,

> the caller then mistakenly started calling the function around
> 34a4ae55 (log --grep: use the same helper to set -E/-F options as
> "git grep", 2012-10-03), instead of setting the .pattern_type_option
> field and letting the grep_commit_pattern_type() to take care of the
> details.
>
> This caused an unnecessary bug that made a configured
> grep.patternType take precedence over the command line options
> (e.g. --basic-regexp, --fixed-strings) in "git log" family of
> commands.
>
> Signed-off-by: Junio C Hamano <gitster@pobox.com>