[PATCH] ignore: add case-insensitive globs support

[Matt Mackall]

On Wed, 2011-03-30 at 20:19 +0300, Eduard-Cristian Stefan wrote:
> On 2011-03-30 16:21, Matt Mackall wrote:
> > On Wed, 2011-03-30 at 14:50 +0300, Eduard-Cristian Stefan wrote:
> >> ignore: add case-insensitive globs support
> > [...]
> >> -def _globre(pat):
> >> +def _globre(pat, ci=False):
> >>      "convert a glob pattern into a regexp"
> >>      i, n = 0, len(pat)
> >> -    res = ''
> >> +    res = ['', '(?i)'][ci]
> >>      group = 0
> >>      escape = re.escape
> >>      def peek():
> > 
> > I'm afraid this won't work. It will make -all- ignore patterns case
> > insensitive. We join all the regexes into a single expression for
> > performance and the flag is global.
> 
> You are right, but I think I've found a bug. In an empty repo,
> for this list of files:
> 
>     1.bak
>     2.BaK
>     3.log
>     4.LoG
>     5.res
>     6.ReS
>     7.txt
>     8.TxT
> 
> if .hgignore contains:
> 
>     syntax: glob
>     *.bak
> 
>     syntax: regexp
>     ^.*\.res$
>     ^.*\.txt$
> 
> then hg status returns as expected:
> 
>     ? .hgignore
>     ? 2.BaK
>     ? 3.log
>     ? 4.LoG
>     ? 6.ReS
>     ? 8.TxT
> 
> But if I modify .hgignore to ignore *.txt case-insensitive:
> 
>     syntax: glob
>     *.bak
> 
>     syntax: regexp
>     ^.*\.res$
>     (?i)^.*\.txt$
> 
> then hg status seems to treat all ignore patterns as case-insensitive:
> 
>     ? .hgignore
>     ? 3.log
>     ? 4.LoG
> 
> OTOH, if this behavior is by design, then simply adding a line like:
> 
>     syntax: regexp
>     (?i)^nonexistentfile$

Yep, setting any of the (?x) flags in any pattern will have a global
effect across patterns. In general, doing "clever" things with ignore
regexes probably won't do what you want.

-- 
Mathematics is the supreme nostalgia of our time.