[PATCH V2] revset: add "matching" keyword

[Angel Ezquerra]

On Thu, Apr 5, 2012 at 11:03 PM, Matt Mackall <mpm at selenic.com> wrote:
> On Wed, 2012-04-04 at 00:56 +0200, Angel Ezquerra wrote:
>> # HG changeset patch
>> # User Angel Ezquerra <angel.ezquerra at gmail.com>
>> # Date 1333282334 -7200
>> # Node ID 3e65ae4b56dbc669c90613be40fb5b0f7cbe30e2
>> # Parent  f350021ee32ed22b8bd7d3211a8899df0e3d6552
>> revset: add "matching" keyword
>>
>> This keyword can be used to find revisions that "match" one or more fields of a
>> given set of revisions.
>>
>> A revision matches another if all the selected fields (description, author,
>> files, date, parents and/or substate) match the corresponding values of those
>> fields on the source revision.
>>
>> By default this keyword looks for revisions that whose metadata match
>> (description, author and date) making it ideal to look for duplicate revisions.
>>
>> matching takes 2 arguments (the second being optional):
>>
>> 1.- rev: a revset represeting a _single_ revision (e.g. tip, ., p1(.), etc)
>> 2.- [field(s) to match]: an optional field or list of fields to match.
>>   By default matching will match the metadata fields (description, author and
>>   date). When matching more than one field, they must be input as a list. When
>>   matching a single field there is no need to surround it in () to make it a
>>   list.
>>
>> Examples:
>>
>> 1.- Look for revisions with the same metadata (author, description and date)
>> as the 11th revision:
>>
>> hg log -r "matching(11)"
>>
>> 2.- Look for revisions with the same description as the 11th revision:
>>
>> hg log -r "matching(11, description)"
>>
>> You do not need to type the whole 'description' word. You could also use
>> 'descript' or 'desc' but not 'd' because 'd' also matches 'date' and 'date'
>> takes prefecedence because fields are matched in alphabetical order.
>>
>> 3.- Look for revisions with the same author as the current revision:
>>
>> hg log -r "matching(., author)"
>>
>> You could use 'user' rather than 'author' to get the same result.
>>
>> 4.- Look for revisions with the same description _AND_ author as the tip of the
>> repository:
>>
>> hg log -r "matching(tip, (author, desc))"
>
> This second arg is a bit weird. Subexpressions are normally revsets, so
> this could confuse things like the optimizer and the alias engine.
> Compare sort, which instead does:
>
> sort(<some expression>, "author desc")

OK, I'll change it to only accept a string and do a split to get a
list of fields instead.

What do you think about specifying the order in which fields are
matched rather than relying on it being done on alphabetical order?

Angel