view tests/test-pathconflicts-merge.t @ 40056:324b4b10351e

revlog: rewrite censoring logic

I was able to corrupt a revlog relatively easily with the existing
censoring code. The underlying problem is that the existing code
doesn't fully take delta chains into account. When copying revisions
that occur after the censored revision, the delta base can refer
to a censored revision. Then at read time, things blow up due to the
revision data not being a compressed delta.

This commit rewrites the revlog censoring code to take a higher-level
approach. We now create a new revlog instance pointing at temp files.
We iterate through each revision in the source revlog and insert
those revisions into the new revlog, replacing the censored revision's
data along the way.

The new implementation isn't as efficient as the old one. This is
because it will fully engage delta computation on insertion. But I
don't think it matters.

The new implementation is a bit hacky because it attempts to reload
the revlog instance with a new revlog index/data file. This is fragile.
But this is needed because the index (which could be backed by C) would
have a cached copy of the old, possibly changed data and that could
lead to problems accessing index or revision data later.

One benefit of the new approach is that we integrate with the
transaction. The old revlog is backed up and if the transaction is
rolled back, the original revlog is restored.

As part of this, we had to teach the transaction about the store
vfs. I'm not super keen about this. But this was the easiest way
to hook things up to the transaction. We /could/ just ignore the
transaction like we were doing before. But any file mutation should
be governed by transaction semantics, including undo during rollback.

Differential Revision: https://phab.mercurial-scm.org/D4869

Path conflict checking is currently disabled by default because of issue5716.
Turn it on for this test.

  $ cat >> $HGRCPATH << EOF
  > [experimental]
  > merge.checkpathconflicts=True
  > EOF

  $ hg init repo
  $ cd repo
  $ echo base > base
  $ hg add base
  $ hg commit -m "base"
  $ hg bookmark -i base
  $ mkdir a
  $ echo 1 > a/b
  $ hg add a/b
  $ hg commit -m "file"
  $ hg bookmark -i file
  $ echo 2 > a/b
  $ hg commit -m "file2"
  $ hg bookmark -i file2
  $ hg up 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved

#if symlink
  $ mkdir a
  $ ln -s c a/b
  $ hg add a/b
  $ hg commit -m "link"
  created new head
#else
  $ hg import -q --bypass - <<EOF
  > # HG changeset patch
  > link
  > 
  > diff --git a/a/b b/a/b
  > new file mode 120000
  > --- /dev/null
  > +++ b/a/b
  > @@ -0,0 +1,1 @@
  > +c
  > \ No newline at end of file
  > EOF
  $ hg up -q
#endif

  $ hg bookmark -i link
  $ hg up 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ mkdir -p a/b/c
  $ echo 2 > a/b/c/d
  $ hg add a/b/c/d
  $ hg commit -m "dir"
  created new head
  $ hg bookmark -i dir

Merge - local file conflicts with remote directory

  $ hg up file
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  (activating bookmark file)
  $ hg bookmark -i
  $ hg merge --verbose dir
  resolving manifests
  a/b: path conflict - a file or link has the same name as a directory
  the local file has been renamed to a/b~0ed027b96f31
  resolve manually then use 'hg resolve --mark a/b'
  moving a/b to a/b~0ed027b96f31
  getting a/b/c/d
  1 files updated, 0 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg merge --abort' to abandon
  [1]
  $ hg status
  M a/b/c/d
  A a/b~0ed027b96f31
  R a/b
  $ hg resolve --all
  a/b: path conflict must be resolved manually
  $ hg forget a/b~0ed027b96f31 && rm a/b~0ed027b96f31
  $ hg resolve --mark a/b
  (no more unresolved files)
  $ hg commit -m "merge file and dir (deleted file)"

Merge - local symlink conflicts with remote directory

  $ hg up link
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  (activating bookmark link)
  $ hg bookmark -i
  $ hg merge dir
  a/b: path conflict - a file or link has the same name as a directory
  the local file has been renamed to a/b~2ea68033e3be
  resolve manually then use 'hg resolve --mark a/b'
  1 files updated, 0 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg merge --abort' to abandon
  [1]
  $ hg status
  M a/b/c/d
  A a/b~2ea68033e3be
  R a/b
  $ hg resolve --list
  P a/b
  $ hg resolve --all
  a/b: path conflict must be resolved manually
  $ hg mv a/b~2ea68033e3be a/b.old
  $ hg resolve --mark a/b
  (no more unresolved files)
  $ hg resolve --list
  R a/b
  $ hg commit -m "merge link and dir (renamed link)"

Merge - local directory conflicts with remote file or link

  $ hg up dir
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  (activating bookmark dir)
  $ hg bookmark -i
  $ hg merge file
  a/b: path conflict - a file or link has the same name as a directory
  the remote file has been renamed to a/b~0ed027b96f31
  resolve manually then use 'hg resolve --mark a/b'
  1 files updated, 0 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg merge --abort' to abandon
  [1]
  $ hg status
  A a/b~0ed027b96f31
  $ hg resolve --all
  a/b: path conflict must be resolved manually
  $ hg mv a/b~0ed027b96f31 a/b/old-b
  $ hg resolve --mark a/b
  (no more unresolved files)
  $ hg commit -m "merge dir and file (move file into dir)"
  created new head
  $ hg merge file2
  merging a/b/old-b and a/b to a/b/old-b
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ cat a/b/old-b
  2
  $ hg commit -m "merge file2 (copytrace tracked rename)"
  $ hg merge link
  a/b: path conflict - a file or link has the same name as a directory
  the remote file has been renamed to a/b~2ea68033e3be
  resolve manually then use 'hg resolve --mark a/b'
  1 files updated, 0 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg merge --abort' to abandon
  [1]
  $ hg mv a/b~2ea68033e3be a/b.old

#if symlink
  $ readlink.py a/b.old
  a/b.old -> c
#else
  $ cat a/b.old
  c (no-eol)
#endif

  $ hg resolve --mark a/b
  (no more unresolved files)
  $ hg commit -m "merge link (rename link)"