tests/test-resolve.t

changelog: add a `branch` method, bypassing changectx

The only way to access the branch of a changeset is currently to
create a changectx object and access its `branch()` method. Creating
a new Python object is costly and has a huge impact on code doing
heavy access to `branch()` (like branchmap).

This change introduces a new method on changelog that allows direct
access to the branch of a revision. See the next changeset for impact.

test that a commit clears the merge state.

  $ hg init repo
  $ cd repo

  $ echo foo > file
  $ hg commit -Am 'add file'
  adding file

  $ echo bar >> file
  $ hg commit -Am 'append bar'


create a second head

  $ hg up -C 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo baz >> file
  $ hg commit -Am 'append baz'
  created new head

failing merge

  $ hg merge --tool=internal:fail
  0 files updated, 0 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
  [1]

  $ echo resolved > file
  $ hg resolve -m file
  $ hg commit -m 'resolved'

resolve -l, should be empty

  $ hg resolve -l

test crashed merge with empty mergestate

  $ mkdir .hg/merge
  $ touch .hg/merge/state

resolve -l, should be empty

  $ hg resolve -l

  $ cd ..