[ENHANCEMENT] Allow '**' pattern in .gitignore

> Hi,
> 
> I've often found the '**' (extended) shell glob useful for matching
> any string crossing directory boundaries: it's especially useful if
> you only have a toplevel .gitignore, as opposed to a per-directory
> .gitignore.  Unfortunately, .gitignore currently uses fnmatch(3), and
> doesn't recognize '**'.  Would extending the .gitignore format to
> accept this be a useful feature?  Would it involve re-implementing and
> extending fnmatch, or is there some other way?
>

> On 10/02/2012 09:21 AM, Ramkumar Ramachandra wrote:
>> Hi,
>>
>> I've often found the '**' (extended) shell glob useful for matching
>> any string crossing directory boundaries: it's especially useful if
>> you only have a toplevel .gitignore, as opposed to a per-directory
>> .gitignore.  Unfortunately, .gitignore currently uses fnmatch(3), and
>> doesn't recognize '**'.  Would extending the .gitignore format to
>> accept this be a useful feature?  Would it involve re-implementing and
>> extending fnmatch, or is there some other way?
>>
> I think there is a topic in flight about this:
>
>     <http://thread.gmane.org/gmane.comp.version-control.git/206406>

> Stefano Lattarini wrote:
>> On 10/02/2012 09:21 AM, Ramkumar Ramachandra wrote:
>>> Hi,
>>>
>>> I've often found the '**' (extended) shell glob useful for matching
>>> any string crossing directory boundaries: it's especially useful if
>>> you only have a toplevel .gitignore, as opposed to a per-directory
>>> .gitignore.  Unfortunately, .gitignore currently uses fnmatch(3), and
>>> doesn't recognize '**'.  Would extending the .gitignore format to
>>> accept this be a useful feature?  Would it involve re-implementing and
>>> extending fnmatch, or is there some other way?
>>>
>> I think there is a topic in flight about this:
>>
>>     <http://thread.gmane.org/gmane.comp.version-control.git/206406>

> On Tue, Oct 2, 2012 at 3:24 PM, Ramkumar Ramachandra <artagnon@gmail.com> wrote:
>> Stefano Lattarini wrote:
>>> On 10/02/2012 09:21 AM, Ramkumar Ramachandra wrote:
>>>> Hi,
>>>>
>>>> I've often found the '**' (extended) shell glob useful for matching
>>>> any string crossing directory boundaries: it's especially useful if
>>>> you only have a toplevel .gitignore, as opposed to a per-directory
>>>> .gitignore.  Unfortunately, .gitignore currently uses fnmatch(3), and
>>>> doesn't recognize '**'.  Would extending the .gitignore format to
>>>> accept this be a useful feature?  Would it involve re-implementing and
>>>> extending fnmatch, or is there some other way?
>>>>
>>> I think there is a topic in flight about this:
>>>
>>>     <http://thread.gmane.org/gmane.comp.version-control.git/206406>
> 
> While I'm behind this series, I have no use cases for it in my
> repositories. It's tested in git test suite but that's about it. Some
> feedback would be nice, especially on the performance side if you do a
> lot of ignores.

> */foo/bar
> */*/foo/bar
> */*/*/foo/bar
>
> Using "**/foo/bar" instead would be a great improvement

> On Wed, Oct 3, 2012 at 8:35 PM, Jens Lehmann <Jens.Lehmann@web.de> wrote:
>> */foo/bar
>> */*/foo/bar
>> */*/*/foo/bar
>>
>> Using "**/foo/bar" instead would be a great improvement
> 
> If this "**/foo/bar" (i.e. no wildcards except one ** at the
> beginning) is popular, we could optimize this case, turning fmatch()
> into strncmp(), just like what we do for "foobar*"

> On Wed, Oct 3, 2012 at 8:35 PM, Jens Lehmann <Jens.Lehmann@web.de> wrote:
>> */foo/bar
>> */*/foo/bar
>> */*/*/foo/bar
>>
>> Using "**/foo/bar" instead would be a great improvement
> If this "**/foo/bar" (i.e. no wildcards except one ** at the
> beginning) is popular, we could optimize this case, turning fmatch()
> into strncmp(), just like what we do for "foobar*"