tests/test-merge-remove.t

help: add internals.extensions topic

I think it's better to include the API overview in core as we now have the
internals section in our help system.

Retrieved from the wiki, and formatted as reST. Several wiki links are
removed since they are invalid in the help. The sections about example
extension are removed at all as they seemed too verbose.

https://www.mercurial-scm.org/wiki/WritingExtensions

  $ 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].
  What do you want to do?
  use (c)hanged version, leave (d)eleted, or leave (u)nresolved? 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