util._matcher: speed up regexp matching.
In 4babaa52badf, Benoit made a change that substantially slows matching
when a big .hgignore file is in play, because it calls into the regexp
matching engine potentially hundreds of times per file to be matched.
I've partly rolled back his change, so that we only call into the matcher
once per file, but preserved the ability to report a meaningful error
message if there's a syntax error in the regexp.
#!/bin/sh
echo '% Show all commands except debug commands'
hg debugcomplete
echo
echo '% Show all commands that start with "a"'
hg debugcomplete a
echo
echo '% Do not show debug commands if there are other candidates'
hg debugcomplete d
echo
echo '% Show debug commands if there are no other candidates'
hg debugcomplete debug
echo
echo '% Do not show the alias of a debug command if there are other candidates'
echo '% (this should hide rawcommit)'
hg debugcomplete r
echo
echo '% Show the alias of a debug command if there are no other candidates'
hg debugcomplete rawc
echo
echo '% Show the global options'
hg debugcomplete --options | sort
echo
echo '% Show the options for the "serve" command'
hg debugcomplete --options serve | sort
echo
echo '% Show an error if we use --options with an ambiguous abbreviation'
hg debugcomplete --options s
exit 0