[PATCH 1/2] __git_recent_branches: Retrieve less data, but faster.

[Daniel Shahaf <d.s@xxxxxxxxxxxxxxxxxx>]

By replacing the --grep-reflog=needle argument with a ${(M)...:#needle} filter,
we retrieve less data from the reflog, and consequently run (on my test cases)
16% to 40% faster.  The trade-off is that we retrieve less data: instead of
retrieving the 1000 most recent 'checkout' operations, we retrieve the most
recent 1000 operations, which would include fewer than 1000 checkout operations.

Also change [[:xdigit:]] to [0-9a-f] since it's faster, however, the absolute
gain from this is minor compared to the cost of 'git reflog'.
---
 Completion/Unix/Command/_git | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Completion/Unix/Command/_git b/Completion/Unix/Command/_git
index 43cbc46..73daedc 100644
--- a/Completion/Unix/Command/_git
+++ b/Completion/Unix/Command/_git
@@ -6126,12 +6126,13 @@ __git_recent_branches__names()
   # 2. Extracts the move-source from each
   # 3. Eliminates duplicates
   # 4. Eliminates commit hashes (leaving only ref names)
+  #    [This step is done again by the caller.]
   #
   # See workers/38592 for an equivalent long-hand implementation, and the rest
   # of that thread for why this implementation was chosen instead.
   #
   # Note: since we obtain the "from" part of the reflog, we only obtain heads, not tags.
-  reply=(${${(u)${${(0)"$(_call_program reflog git reflog -1000 -z --grep-reflog='\^checkout:\ moving\ from\ ' --pretty='%gs')"}#checkout: moving from }%% *}:#[[:xdigit:]](#c40)})
+  reply=(${${(u)${${(M)${(0)"$(_call_program reflog git reflog -1000 -z --pretty='%gs')"}:#(#s)checkout: moving from *}#checkout: moving from }%% *}:#[0-9a-f](#c40)})
 }
 
 (( $+functions[__git_recent_branches] )) ||