histedit: add experimental config for using the first word of the commit
This allows users to start a commit with "verb! ..." so that when this is
opened in histedit, the default action will be "verb". For example, "roll! foo"
will default to the action "roll". Currently, we'll allow any known verb to be
used but this is experimental.
#require execbit
$ hg init
$ echo a > a
$ hg ci -Am'not executable'
adding a
$ chmod +x a
$ hg ci -m'executable'
$ hg id
79abf14474dc tip
Make sure we notice the change of mode if the cached size == -1:
$ hg rm a
$ hg revert -r 0 a
$ hg debugstate
n 0 -1 unset a
$ hg status
M a
$ hg up 0
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg id
d69afc33ff8a
$ test -x a && echo executable -- bad || echo not executable -- good
not executable -- good