debugbuilddag: use memctx for speed
This drops the options to run arbitrary shell commands within
commits and the option to create a file that gets appended to
in every revision. It now supports to not write file data at
all, which is very fast for generating a pure 00changelog.i
(useful for discovery tests, for instance).
Timings for 1000 linear nodes:
* Old `hg debugbuilddag -o '+1000'` took 4.5 secs.
* New `hg debugbuilddag -o '+1000'` takes 2 secs.
* New `hg debugbuilddag '+1000'` takes 0.8 secs.
(The last one creates only 00changelog.i).
test --time
$ hg --time help -q help 2>&1 | grep Time > /dev/null
$ hg init a
$ cd a
test --profile
$ if "$TESTDIR/hghave" -q lsprof; then
> hg --profile st 2>../out || echo --profile failed
> grep CallCount < ../out > /dev/null || echo wrong --profile
>
> hg --profile --config profiling.output=../out st 2>&1 \
> || echo --profile + output to file failed
> grep CallCount < ../out > /dev/null \
> || echo wrong --profile output when saving to a file
>
> hg --profile --config profiling.format=text st 2>&1 \
> | grep CallCount > /dev/null || echo --profile format=text failed
>
> echo "[profiling]" >> $HGRCPATH
> echo "format=kcachegrind" >> $HGRCPATH
>
> hg --profile st 2>../out || echo --profile format=kcachegrind failed
> grep 'events: Ticks' < ../out > /dev/null || echo --profile output is wrong
>
> hg --profile --config profiling.output=../out st 2>&1 \
> || echo --profile format=kcachegrind + output to file failed
> grep 'events: Ticks' < ../out > /dev/null \
> || echo --profile output is wrong
> fi