view tests/test-sparse-merges.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

test merging things outside of the sparse checkout

  $ hg init myrepo
  $ cd myrepo
  $ cat > .hg/hgrc <<EOF
  > [extensions]
  > sparse=
  > EOF

  $ echo foo > foo
  $ echo bar > bar
  $ hg add foo bar
  $ hg commit -m initial

  $ hg branch feature
  marked working directory as branch feature
  (branches are permanent and global, did you want a bookmark?)
  $ echo bar2 >> bar
  $ hg commit -m 'feature - bar2'

  $ hg update -q default
  $ hg debugsparse --exclude 'bar**'

  $ hg merge feature
  temporarily included 1 file(s) in the sparse checkout for merging
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)

Verify bar was merged temporarily

  $ ls
  bar
  foo
  $ hg status
  M bar

Verify bar disappears automatically when the working copy becomes clean

  $ hg commit -m "merged"
  cleaned up 1 temporarily added file(s) from the sparse checkout
  $ hg status
  $ ls
  foo

  $ hg cat -r . bar
  bar
  bar2

Test merging things outside of the sparse checkout that are not in the working
copy

  $ hg strip -q -r . --config extensions.strip=
  $ hg up -q feature
  $ touch branchonly
  $ hg ci -Aqm 'add branchonly'

  $ hg up -q default
  $ hg debugsparse -X branchonly
  $ hg merge feature
  temporarily included 2 file(s) in the sparse checkout for merging
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)

  $ cd ..

Tests merging a file which is modified in one branch and deleted in another and
file is excluded from sparse checkout

  $ hg init ytest
  $ cd ytest
  $ echo "syntax: glob" >> .hgignore
  $ echo "*.orig" >> .hgignore
  $ hg ci -Aqm "added .hgignore"
  $ for ch in a d; do echo foo > $ch; hg ci -Aqm "added "$ch; done;
  $ cat >> .hg/hgrc <<EOF
  > [alias]
  > glog = log -GT "{rev}:{node|short} {desc}"
  > [extensions]
  > sparse =
  > EOF

  $ hg glog
  @  2:f29feff37cfc added d
  |
  o  1:617125d27d6b added a
  |
  o  0:53f3774ed939 added .hgignore
  
  $ hg rm d
  $ hg ci -m "removed d"

  $ hg up '.^'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg debugsparse --reset
  $ echo bar >> d
  $ hg ci -Am "added bar to d"
  created new head

  $ hg glog
  @  4:6527874a90e4 added bar to d
  |
  | o  3:372c8558de45 removed d
  |/
  o  2:f29feff37cfc added d
  |
  o  1:617125d27d6b added a
  |
  o  0:53f3774ed939 added .hgignore
  
  $ hg debugsparse --exclude "d"
  $ ls
  a

  $ hg merge
  temporarily included 1 file(s) in the sparse checkout for merging
  file 'd' was deleted in other [merge rev] but was modified in local [working copy].
  What do you want to do?
  use (c)hanged version, (d)elete, or leave (u)nresolved? u
  0 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]

  $ cd ..

Testing merging of a file which is renamed+modified on one side and modified on
another

  $ hg init mvtest
  $ cd mvtest
  $ echo "syntax: glob" >> .hgignore
  $ echo "*.orig" >> .hgignore
  $ hg ci -Aqm "added .hgignore"
  $ for ch in a d; do echo foo > $ch; hg ci -Aqm "added "$ch; done;
  $ cat >> .hg/hgrc <<EOF
  > [alias]
  > glog = log -GT "{rev}:{node|short} {desc}"
  > [extensions]
  > sparse =
  > EOF

  $ hg glog
  @  2:f29feff37cfc added d
  |
  o  1:617125d27d6b added a
  |
  o  0:53f3774ed939 added .hgignore
  
  $ echo babar >> a
  $ hg ci -m "added babar to a"

  $ hg up '.^'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg mv a amove
  $ hg ci -m "moved a to amove"
  created new head

  $ hg up 3
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg glog
  o  4:5d1e85955f6d moved a to amove
  |
  | @  3:a06e41a6c16c added babar to a
  |/
  o  2:f29feff37cfc added d
  |
  o  1:617125d27d6b added a
  |
  o  0:53f3774ed939 added .hgignore
  
  $ hg debugsparse --exclude "a"
  $ ls
  d

  $ hg merge
  temporarily included 1 file(s) in the sparse checkout for merging
  merging a and amove to amove
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)

  $ hg up -C 4
  cleaned up 1 temporarily added file(s) from the sparse checkout
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ hg merge
  merging amove and a to amove
  abort: cannot add 'a' - it is outside the sparse checkout
  (include file with `hg debugsparse --include <pattern>` or use `hg add -s <file>` to include file directory while adding)
  [255]