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.
$ hg init
$ echo foo > foo
$ echo bar > bar
$ hg ci -qAm 'add foo bar'
$ echo foo2 >> foo
$ echo bleh > bar
$ hg ci -m 'change foo bar'
$ hg up -qC 0
$ hg mv foo foo1
$ echo foo1 > foo1
$ hg cat foo >> foo1
$ hg ci -m 'mv foo foo1'
created new head
$ hg merge
merging foo1 and foo to foo1
1 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg debugstate --no-dates
m 0 -2 unset bar
m 0 -2 unset foo1
copy: foo -> foo1
$ hg st -q
M bar
M foo1
Removing foo1 and bar:
$ cp foo1 F
$ cp bar B
$ hg rm -f foo1 bar
$ hg debugstate --no-dates
r 0 -1 set bar
r 0 -1 set foo1
copy: foo -> foo1
$ hg st -qC
R bar
R foo1
Re-adding foo1 and bar:
$ cp F foo1
$ cp B bar
$ hg add -v foo1 bar
adding bar
adding foo1
$ hg debugstate --no-dates
n 0 -2 unset bar
n 0 -2 unset foo1
copy: foo -> foo1
$ hg st -qC
M bar
M foo1
foo
Reverting foo1 and bar:
$ hg revert -vr . foo1 bar
saving current version of bar as bar.orig
saving current version of foo1 as foo1.orig
reverting bar
reverting foo1
$ hg debugstate --no-dates
n 0 -2 unset bar
n 0 -2 unset foo1
copy: foo -> foo1
$ hg st -qC
M bar
M foo1
foo
$ hg diff
Merge should not overwrite local file that is untracked after remove
$ rm *
$ hg up -qC
$ hg rm bar
$ hg ci -m 'remove bar'
$ echo 'memories of buried pirate treasure' > bar
$ hg merge
bar: untracked file differs
abort: untracked files in working directory differ from files in requested revision
[255]
$ cat bar
memories of buried pirate treasure
Those who use force will lose
$ hg merge -f
file 'bar' was deleted in local [working copy] but was modified in other [merge rev].
You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
What do you want to do? u
merging foo1 and foo to foo1
0 files updated, 1 files merged, 0 files removed, 1 files unresolved
use 'hg resolve' to retry unresolved file merges or 'hg merge --abort' to abandon
[1]
$ cat bar
bleh
$ hg st
M bar
M foo1