tests/test-merge-types.t

largefiles: don't verify largefile hashes on servers when processing statlfile

When changesets referencing largefiles are pushed then the corresponding
largefiles will be pushed too - unless the target already has them. The client
will use statlfile to make sure it only sends largefiles that the target
doesn't have. The server would however on every statlfile check that the
content of the largefile had the expected hash. What should be cheap thus
became an expensive operation that trashed the disk and the cache.

Largefile hashes are already checked by putlfile before being stored on the
server. A server should thus be able to keep its largefile store free of
errors - even more than it can keep revlogs free of errors. Verification should
happen when running 'hg verify' locally on the server. Rehashing every
largefile on every remote stat is too expensive.

Clients will also stat lfiles before downloading them. When the server verified
the hash in stat it meant that it had to read the file twice to serve it.

With this change the server will assume its own hashes are ok without checking
them on every statlfile.

Some consequences of this change:
- in case of server side corruption the problem will be detected by the
  existing check on the client side - not on server side
- clients that could upload an uncorrupted largefile when pushing will no
  longer magically heal the server (and break hardlinks) - a client will now
  only upload its uncorrupted files after the corrupted file has been removed
  on the server side
- client side verify will no longer report corruption in files it doesn't have

(Issue3123 discussed related problems - and how they have been fixed.)

  $ "$TESTDIR/hghave" symlink execbit || exit 80

  $ tellmeabout() {
  > if [ -h $1 ]; then
  >     echo $1 is a symlink:
  >     $TESTDIR/readlink.py $1
  > elif [ -x $1 ]; then
  >     echo $1 is an executable file with content:
  >     cat $1
  > else
  >     echo $1 is a plain file with content:
  >     cat $1
  > fi
  > }

  $ hg init test1
  $ cd test1

  $ echo a > a
  $ hg ci -Aqmadd
  $ chmod +x a
  $ hg ci -mexecutable

  $ hg up -q 0
  $ rm a
  $ ln -s symlink a
  $ hg ci -msymlink
  created new head

Symlink is local parent, executable is other:

  $ hg merge --debug
    searching for copies back to rev 1
  resolving manifests
   overwrite: False, partial: False
   ancestor: c334dc3be0da, local: 521a1e40188f+, remote: 3574f3e69b1c
   a: versions differ -> m
  preserving a for resolve of a
  updating: a 1/1 files (100.00%)
  picked tool 'internal:merge' for a (binary False symlink True)
  merging a
  my a@521a1e40188f+ other a@3574f3e69b1c ancestor a@c334dc3be0da
  warning: internal:merge cannot merge symlinks for a
  merging a incomplete! (edit conflicts, then use 'hg resolve --mark')
  0 files updated, 0 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
  [1]

  $ tellmeabout a
  a is a symlink:
  a -> symlink
  $ hg resolve a --tool internal:other
  $ tellmeabout a
  a is an executable file with content:
  a
  $ hg st
  M a
  ? a.orig

Symlink is other parent, executable is local:

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

  $ hg merge --debug
    searching for copies back to rev 1
  resolving manifests
   overwrite: False, partial: False
   ancestor: c334dc3be0da, local: 3574f3e69b1c+, remote: 521a1e40188f
   a: versions differ -> m
  preserving a for resolve of a
  updating: a 1/1 files (100.00%)
  picked tool 'internal:merge' for a (binary False symlink True)
  merging a
  my a@3574f3e69b1c+ other a@521a1e40188f ancestor a@c334dc3be0da
  warning: internal:merge cannot merge symlinks for a
  merging a incomplete! (edit conflicts, then use 'hg resolve --mark')
  0 files updated, 0 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
  [1]

  $ tellmeabout a
  a is an executable file with content:
  a

Update to link without local change should get us a symlink (issue3316):

  $ hg up -C 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg up
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg st
  ? a.orig

Update to link with local change should cause a merge prompt (issue3200):

  $ hg up -Cq 0
  $ echo data > a
  $ HGMERGE= hg up -y --debug
    searching for copies back to rev 2
  resolving manifests
   overwrite: False, partial: False
   ancestor: c334dc3be0da, local: c334dc3be0da+, remote: 521a1e40188f
   a: versions differ -> m
  preserving a for resolve of a
  updating: a 1/1 files (100.00%)
  (couldn't find merge tool hgmerge|tool hgmerge can't handle symlinks) (re)
  picked tool 'internal:prompt' for a (binary False symlink True)
   no tool found to merge a
  keep (l)ocal or take (o)ther? l
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  $ hg diff --git
  diff --git a/a b/a
  old mode 120000
  new mode 100644
  --- a/a
  +++ b/a
  @@ -1,1 +1,1 @@
  -symlink
  \ No newline at end of file
  +data


Test only 'l' change - happens rarely, except when recovering from situations
where that was what happened.

  $ hg init test2
  $ cd test2
  $ printf base > f
  $ hg ci -Aqm0
  $ echo file > f
  $ echo content >> f
  $ hg ci -qm1
  $ hg up -qr0
  $ rm f
  $ ln -s base f
  $ hg ci -qm2
  $ hg merge
  merging f
  warning: internal:merge cannot merge symlinks for f
  merging f incomplete! (edit conflicts, then use 'hg resolve --mark')
  0 files updated, 0 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
  [1]
  $ tellmeabout f
  f is a symlink:
  f -> base

  $ hg up -Cqr1
  $ hg merge
  merging f
  warning: internal:merge cannot merge symlinks for f
  merging f incomplete! (edit conflicts, then use 'hg resolve --mark')
  0 files updated, 0 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
  [1]
  $ tellmeabout f
  f is a plain file with content:
  file
  content

  $ cd ..

Test removed 'x' flag merged with change to symlink

  $ hg init test3
  $ cd test3
  $ echo f > f
  $ chmod +x f
  $ hg ci -Aqm0
  $ chmod -x f
  $ hg ci -qm1
  $ hg up -qr0
  $ rm f
  $ ln -s dangling f
  $ hg ci -qm2
  $ hg merge
  merging f
  warning: internal:merge cannot merge symlinks for f
  merging f incomplete! (edit conflicts, then use 'hg resolve --mark')
  0 files updated, 0 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
  [1]
  $ tellmeabout f
  f is a symlink:
  f -> dangling

  $ hg up -Cqr1
  $ hg merge
  merging f
  warning: internal:merge cannot merge symlinks for f
  merging f incomplete! (edit conflicts, then use 'hg resolve --mark')
  0 files updated, 0 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
  [1]
  $ tellmeabout f
  f is a plain file with content:
  f

  $ cd ..

Test merge with no common ancestor:
a: just different
b: x vs -, different (cannot calculate x, cannot ask merge tool)
c: x vs -, same (cannot calculate x, merge tool is no good)
d: x vs l, different
e: x vs l, same
f: - vs l, different
g: - vs l, same
h: l vs l, different
(where same means the filelog entry is shared and there thus is an ancestor!)

  $ hg init test4
  $ cd test4
  $ echo 0 > 0
  $ hg ci -Aqm0

  $ echo 1 > a
  $ echo 1 > b
  $ chmod +x b
  $ echo x > c
  $ chmod +x c
  $ echo 1 > d
  $ chmod +x d
  $ printf x > e
  $ chmod +x e
  $ echo 1 > f
  $ printf x > g
  $ ln -s 1 h
  $ hg ci -qAm1

  $ hg up -qr0
  $ echo 2 > a
  $ echo 2 > b
  $ echo x > c
  $ ln -s 2 d
  $ ln -s x e
  $ ln -s 2 f
  $ ln -s x g
  $ ln -s 2 h
  $ hg ci -Aqm2

  $ hg merge
  merging a
  warning: conflicts during merge.
  merging a incomplete! (edit conflicts, then use 'hg resolve --mark')
  warning: cannot merge flags for b
  merging b
  warning: conflicts during merge.
  merging b incomplete! (edit conflicts, then use 'hg resolve --mark')
  merging d
  warning: internal:merge cannot merge symlinks for d
  merging d incomplete! (edit conflicts, then use 'hg resolve --mark')
  merging f
  warning: internal:merge cannot merge symlinks for f
  merging f incomplete! (edit conflicts, then use 'hg resolve --mark')
  merging h
  warning: internal:merge cannot merge symlinks for h
  merging h incomplete! (edit conflicts, then use 'hg resolve --mark')
  3 files updated, 0 files merged, 0 files removed, 5 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
  [1]
  $ hg resolve -l
  U a
  U b
  U d
  U f
  U h
  $ tellmeabout a
  a is a plain file with content:
  <<<<<<< local
  2
  =======
  1
  >>>>>>> other
  $ tellmeabout b
  b is a plain file with content:
  <<<<<<< local
  2
  =======
  1
  >>>>>>> other
  $ tellmeabout c
  c is a plain file with content:
  x
  $ tellmeabout d
  d is a symlink:
  d -> 2
  $ tellmeabout e
  e is a symlink:
  e -> x
  $ tellmeabout f
  f is a symlink:
  f -> 2
  $ tellmeabout g
  g is a symlink:
  g -> x
  $ tellmeabout h
  h is a symlink:
  h -> 2

  $ hg up -Cqr1
  $ hg merge
  merging a
  warning: conflicts during merge.
  merging a incomplete! (edit conflicts, then use 'hg resolve --mark')
  warning: cannot merge flags for b
  merging b
  warning: conflicts during merge.
  merging b incomplete! (edit conflicts, then use 'hg resolve --mark')
  merging d
  warning: internal:merge cannot merge symlinks for d
  merging d incomplete! (edit conflicts, then use 'hg resolve --mark')
  merging f
  warning: internal:merge cannot merge symlinks for f
  merging f incomplete! (edit conflicts, then use 'hg resolve --mark')
  merging h
  warning: internal:merge cannot merge symlinks for h
  merging h incomplete! (edit conflicts, then use 'hg resolve --mark')
  3 files updated, 0 files merged, 0 files removed, 5 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
  [1]
  $ tellmeabout a
  a is a plain file with content:
  <<<<<<< local
  1
  =======
  2
  >>>>>>> other
  $ tellmeabout b
  b is an executable file with content:
  <<<<<<< local
  1
  =======
  2
  >>>>>>> other
  $ tellmeabout c
  c is a plain file with content:
  x
  $ tellmeabout d
  d is an executable file with content:
  1
  $ tellmeabout e
  e is an executable file with content:
  x (no-eol)
  $ tellmeabout f
  f is a plain file with content:
  1
  $ tellmeabout g
  g is a plain file with content:
  x (no-eol)
  $ tellmeabout h
  h is a symlink:
  h -> 1

  $ cd ..