view tests/test-issue522.t @ 23996:0188c2d90356

trydiff: check only if added file is a copy target, not source

When creating a diff with copy/rename enabled, we consider added files
and check if they are either copy sources or targets. However, an
added file should never be a copy source. The test suite seems to
agree with this: all tests pass if we raise an exception when an added
file is a copy source. So, let's simplify the code by dropping the
conditions that are never true.

For those interested in the historical reasons:

Before commit d1f209bb9564 (patch: separate reverse copy data
(issue1959), 2010-02-11), 'copy' seems to have been a bidirectional
map. Then that commit split it up into two unidirectional maps and
duplicated the logic to look in both maps. It was still needed at that
point to look in both maps, as the copy detection was poor and could
sometimes be reported in reverse.

A little later came 91eb4512edd0 (copies: rewrite copy detection for
non-merge users, 2012-01-04). That commit fixed the copy detection to
be backwards when it should, and made the hacks in trydiff
unnecessary.

http://mercurial.selenic.com/bts/issue522

In the merge below, the file "foo" has the same contents in both
parents, but if we look at the file-level history, we'll notice that
the version in p1 is an ancestor of the version in p2. This test makes
sure that we'll use the version from p2 in the manifest of the merge
revision.

  $ hg init

  $ echo foo > foo
  $ hg ci -qAm 'add foo'

  $ echo bar >> foo
  $ hg ci -m 'change foo'

  $ hg backout -r tip -m 'backout changed foo'
  reverting foo
  changeset 2:4d9e78aaceee backs out changeset 1:b515023e500e

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

  $ touch bar
  $ hg ci -qAm 'add bar'

  $ hg merge --debug
    searching for copies back to rev 1
    unmatched files in local:
     bar
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: bbd179dfa0a7, local: 71766447bdbb+, remote: 4d9e78aaceee
   foo: remote is newer -> g
  getting foo
  updating: foo 1/1 files (100.00%)
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)

  $ hg debugstate | grep foo
  m   0         -2 unset               foo

  $ hg st -A foo
  M foo

  $ hg ci -m 'merge'

  $ hg manifest --debug | grep foo
  c6fc755d7e68f49f880599da29f15add41f42f5a 644   foo

  $ hg debugindex foo
     rev    offset  length  ..... linkrev nodeid       p1           p2 (re)
       0         0       5  .....       0 2ed2a3912a0b 000000000000 000000000000 (re)
       1         5       9  .....       1 6f4310b00b9a 2ed2a3912a0b 000000000000 (re)
       2        14       5  .....       2 c6fc755d7e68 6f4310b00b9a 000000000000 (re)