# HG changeset patch
# User Anton Shestakov <av6@dwimlabs.net>
# Date 1534854653 -28800
# Node ID 2815e0db4c5475e23a48be78ae615268a53997f0
# Parent  9a813e4c84060e4a7e91f4014dded68cadf59956
zsh_completion: use revsets to exclude this rev from suggestions to hg merge

One of the most important aspects of a completion system is its speed, so 1
call to hg is definitely better than 4.

Sorting by rev (descending) is to preserve the same order as in `hg heads`
output.

While at it, declare branches as an array too.

Differential Revision: https://phab.mercurial-scm.org/D4426

diff -r 9a813e4c8406 -r 2815e0db4c54 contrib/zsh_completion
--- a/contrib/zsh_completion	Tue Sep 04 10:36:34 2018 -0700
+++ b/contrib/zsh_completion	Tue Aug 21 20:30:53 2018 +0800
@@ -193,21 +193,13 @@
 
 # likely merge candidates
 _hg_mergerevs() {
-  typeset -a heads
-  local myrev
+  typeset -a heads branches
+  local revset='sort(head() and not ., -rev)'
 
-  heads=(${(f)"$(_hg_cmd heads --template '{rev}:{branch}\\n')"})
-  # exclude own revision
-  myrev=$(_hg_cmd log -r . --template '{rev}:{branch}\\n')
-  heads=(${heads:#$myrev})
-
+  heads=(${(f)"$(_hg_cmd log -r '$revset' --template '{rev}:{branch}\\n')"})
   (( $#heads )) && _describe -t heads 'heads' heads
 
-  branches=(${(f)"$(_hg_cmd heads --template '{branch}\\n')"})
-  # exclude own revision
-  myrev=$(_hg_cmd log -r . --template '{branch}\\n')
-  branches=(${branches:#$myrev})
-
+  branches=(${(S)heads/#*:/})
   (( $#branches )) && _describe -t branches 'branches' branches
 }