view tests/test-issue522.t @ 22197:f72d73937853

largefiles: update lfdirstate for unchanged largefiles during linear merging

Before this patch, linear merging of modified largefiles causes
an unexpected result, if (1) largefile collides with same-name normal one
in the target revision and (2) "local" largefile is chosen, even
though branch merging between such revisions works correctly.

Expected result of such linear merging is marking the largefile as
(re-)"added", but the actual result is marking it as "modified".

The standin of modified "local largefile" is not changed by linear
merging, and updating/merging update lfdirstate entries only for
largefiles of which standins are changed.

This patch adds the code path to update lfdirstate only for largefiles
of which standins are not changed.

In this case, "synclfdirstate" should be invoked with True as
"normallookup" argument always to force using "normallookup" on
dirstate for "n" files, because "normal" may mark target files as
"clean" unexpectedly.

To reduce cost of "lfile not in filelist", this patch converts
"filelist" to a "set" object: "filelist" is used only in (1) the newly
added code path and (2) the next line of "filelist = set(filelist)".

This is a temporary way to fix with less changes. For fundamental
resolution of this kind of problems in the future, "lfdirstate" should
be updated with "dirstate" simultaneously during "merge.update"
execution: maybe by hooking "recordupdates" (+ total refactoring
around lfdirstate handling)

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
  n   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)