mq: smarter handling of plain headers
6333412245ec and 5ccced6eab0b fixed issue4453 with a simple insertplainheader
function that fixed the regression but didn't make the implementation more
stable.
Now we introduce plain header handling similar to how we handle hg patches. The
whole header is scanned for fields to update while determining the best
position for inserting the field if it is missing. It also makes sure there is
an empty line between headers and body.
test --time
$ hg --time help -q help 2>&1 | grep time > /dev/null
$ hg init a
$ cd a
#if lsprof
test --profile
$ hg --profile st 2>../out
$ grep CallCount ../out > /dev/null || cat ../out
$ hg --profile --config profiling.output=../out st
$ grep CallCount ../out > /dev/null || cat ../out
$ hg --profile --config profiling.format=text st 2>../out
$ grep CallCount ../out > /dev/null || cat ../out
$ echo "[profiling]" >> $HGRCPATH
$ echo "format=kcachegrind" >> $HGRCPATH
$ hg --profile st 2>../out
$ grep 'events: Ticks' ../out > /dev/null || cat ../out
$ hg --profile --config profiling.output=../out st
$ grep 'events: Ticks' ../out > /dev/null || cat ../out
#endif
$ cd ..