absorb: preserve changesets which were already empty
Most commands in Mercurial (commit, rebase, absorb itself) don’t create empty
changesets or drop them if they become empty. If there’s a changeset that’s
empty, it must be a deliberate choice of the user. At least it shouldn’t be
absorb’s responsibility to prune them. The fact that changesets that became
empty during absorb are pruned, is unaffected by this.
This case was found while writing patches which make it possible to configure
absorb and rebase to not drop empty changesets. Even without having such config
set, I think it’s valuable to preserve changesets which were already empty.
Test attempting a narrow clone against a server that doesn't support narrowhg.
$ . "$TESTDIR/narrow-library.sh"
$ hg init master
$ cd master
$ for x in `$TESTDIR/seq.py 10`; do
> echo $x > "f$x"
> hg add "f$x"
> hg commit -m "Add $x"
> done
$ hg serve -a localhost -p $HGPORT1 --config extensions.narrow=! -d \
> --pid-file=hg.pid
$ cat hg.pid >> "$DAEMON_PIDS"
$ hg serve -a localhost -p $HGPORT2 -d --pid-file=hg.pid
$ cat hg.pid >> "$DAEMON_PIDS"
Verify that narrow is advertised in the bundle2 capabilities:
$ cat >> unquote.py <<EOF
> from __future__ import print_function
> import sys
> if sys.version[0] == '3':
> import urllib.parse as up
> unquote = up.unquote_plus
> else:
> import urllib
> unquote = urllib.unquote_plus
> print(unquote(list(sys.stdin)[1]))
> EOF
$ echo hello | hg -R . serve --stdio | \
> "$PYTHON" unquote.py | tr ' ' '\n' | grep narrow
exp-narrow-1
$ cd ..
$ hg clone --narrow --include f1 http://localhost:$HGPORT1/ narrowclone
requesting all changes
abort: server does not support narrow clones
[255]
Make a narrow clone (via HGPORT2), then try to narrow and widen
into it (from HGPORT1) to prove that narrowing is fine and widening fails
gracefully:
$ hg clone -r 0 --narrow --include f1 http://localhost:$HGPORT2/ narrowclone
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
new changesets * (glob)
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd narrowclone
$ hg tracked --addexclude f2 http://localhost:$HGPORT1/
comparing with http://localhost:$HGPORT1/
searching for changes
looking for local changes to affected paths
$ hg tracked --addinclude f1 http://localhost:$HGPORT1/
nothing to widen or narrow
$ hg tracked --addinclude f9 http://localhost:$HGPORT1/
comparing with http://localhost:$HGPORT1/
abort: server does not support narrow clones
[255]