tests/test-merge-closedheads.t

amend: fix copy records handling (issue3410)

Messing with the dirstate before the intermediate commit seems error prone.
Instead, commit and recompute the copies with copies.pathcopies(), then use
that with commitctx().

Since copies.pathcopies() does not support file replacement very well, the
whole .renamed() condition in samefile() is removed and the "file replacement
caused by differing copy source" effect is discarded.

Test shamelessly stolen from Idan Kamara <[e-mail]>

  $ hgcommit() {
  >    hg commit -u user "$@"
  > }

  $ hg init clhead
  $ cd clhead

  $ touch foo && hg add && hgcommit -m 'foo'
  adding foo
  $ touch bar && hg add && hgcommit -m 'bar'
  adding bar
  $ touch baz && hg add && hgcommit -m 'baz'
  adding baz

  $ echo "flub" > foo
  $ hgcommit -m "flub"
  $ echo "nub" > foo
  $ hgcommit -m "nub"

  $ hg up -C 2
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ echo "c1" > c1
  $ hg add c1
  $ hgcommit -m "c1"
  created new head
  $ echo "c2" > c1
  $ hgcommit -m "c2"

  $ hg up -C 2
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved

  $ echo "d1" > d1
  $ hg add d1
  $ hgcommit -m "d1"
  created new head
  $ echo "d2" > d1
  $ hgcommit -m "d2"
  $ hg tag -l good

fail with three heads
  $ hg up -C good
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg merge
  abort: branch 'default' has 3 heads - please merge with an explicit rev
  (run 'hg heads .' to see heads)
  [255]

close one of the heads
  $ hg up -C 6
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hgcommit -m 'close this head' --close-branch

succeed with two open heads
  $ hg up -C good
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg up -C good
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg merge
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hgcommit -m 'merged heads'

hg update -C 8
  $ hg update -C 8
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

hg branch some-branch
  $ hg branch some-branch
  marked working directory as branch some-branch
  (branches are permanent and global, did you want a bookmark?)
hg commit
  $ hgcommit -m 'started some-branch'
hg commit --close-branch
  $ hgcommit --close-branch -m 'closed some-branch'

hg update default
  $ hg update default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
hg merge some-branch
  $ hg merge some-branch
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
hg commit (no reopening of some-branch)
  $ hgcommit -m 'merge with closed branch'