#chg-compatible

  $ configure modern
  $ newrepo basic
  $ drawdag << 'EOS'
  > D
  > |
  > C E   # C/A=(removed)
  > |/    # C/B=B1
  > B
  > |
  > A
  > EOS
  $ hg up -qC $D

should complain

  $ hg backout
  abort: please specify a revision to backout
  [255]
  $ hg backout -r $A $B
  abort: please specify just one revision
  [255]
  $ hg backout $E
  abort: cannot backout change that is not an ancestor
  [255]

basic operation

  $ hg backout -d '1000 +0800' $C --no-edit
  2 files updated, 0 files merged, 1 files removed, 0 files unresolved
  changeset 5:d2f56590172c backs out changeset 2:2e4218cf3ee0

backout of backout is as if nothing happened

  $ hg backout -d '2000 +0800' tip --no-edit
  removing A
  reverting B
  adding C
  changeset 6:6916acf22814 backs out changeset 5:d2f56590172c

check the changes

  $ hg log -Gr 'desc(Back)' -T '{desc}' -p --config diff.git=1
  @  Back out "Back out "C""
  |
  |  Original commit changeset: d2f56590172cdiff --git a/A b/A
  |  deleted file mode 100644
  |  --- a/A
  |  +++ /dev/null
  |  @@ -1,1 +0,0 @@
  |  -A
  |  \ No newline at end of file
  |  diff --git a/B b/B
  |  --- a/B
  |  +++ b/B
  |  @@ -1,1 +1,1 @@
  |  -B
  |  \ No newline at end of file
  |  +B1
  |  \ No newline at end of file
  |  diff --git a/C b/C
  |  new file mode 100644
  |  --- /dev/null
  |  +++ b/C
  |  @@ -0,0 +1,1 @@
  |  +C
  |  \ No newline at end of file
  |
  o  Back out "C"
  |
  ~  Original commit changeset: 2e4218cf3ee0diff --git a/A b/A
     new file mode 100644
     --- /dev/null
     +++ b/A
     @@ -0,0 +1,1 @@
     +A
     \ No newline at end of file
     diff --git a/B b/B
     --- a/B
     +++ b/B
     @@ -1,1 +1,1 @@
     -B1
     \ No newline at end of file
     +B
     \ No newline at end of file
     diff --git a/C b/C
     deleted file mode 100644
     --- a/C
     +++ /dev/null
     @@ -1,1 +0,0 @@
     -C
     \ No newline at end of file
  
test --no-commit

  $ hg up -qC $E
  $ hg backout --no-commit .
  removing E
  changeset 49cb92066bfd backed out, don't forget to commit.
  $ hg diff --config diff.git=1
  diff --git a/E b/E
  deleted file mode 100644
  --- a/E
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -E
  \ No newline at end of file