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).
$ hg init a
$ echo a > a/a
$ hg --cwd a ci -Ama
adding a
$ hg clone a c
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg clone a b
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo b >> b/a
$ hg --cwd b ci -mb
Push should push to 'default' when 'default-push' not set:
$ hg --cwd b push
pushing to $TESTTMP/a
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
Push should push to 'default-push' when set:
$ echo 'default-push = ../c' >> b/.hg/hgrc
$ hg --cwd b push
pushing to $TESTTMP/c
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files