annotate tests/test-pull-pull-corruption.t @ 25591:f1d46075b13a

verify: check the subrepository references in .hgsubstate

While hopefully atypical, there are reasons that a subrepository revision can be
lost that aren't covered by corruption of the .hgsubstate revlog.  Such things
can happen when a subrepo is amended, stripped or simply isn't pulled from
upstream because the parent repo revision wasn't updated yet.  There's no way to
know if it is an error, but this will find potential problems sooner than when
some random revision is updated.

Until recently, convert made no attempt at rewriting the .hgsubstate file.  The
impetuous for this is to verify the conversion of some repositories, and this is
orders of magnitude faster than a bash script from 0..tip that does an
'hg update -C $rev'.  But it is equally useful to determine if everything has
been pulled down before taking a thumb drive on the go.

It feels somewhat wrong to leave this out of verifymod (mostly because the file
is already read in there, and the final summary is printed before the subrepos
are checked).  But verifymod looks very low level, so importing subrepo stuff
there seems more wrong.

Corrupt an hg repo with two pulls.
create one repo with a long history

  $ hg init source1
  $ cd source1
  $ touch foo
  $ hg add foo
  $ for i in 1 2 3 4 5 6 7 8 9 10; do
  >     echo $i >> foo
  >     hg ci -m $i
  > done
  $ cd ..

create one repo with a shorter history

  $ hg clone -r 0 source1 source2
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd source2
  $ echo a >> foo
  $ hg ci -m a
  $ cd ..

create a third repo to pull both other repos into it

  $ hg init corrupted
  $ cd corrupted

use a hook to make the second pull start while the first one is still running

  $ echo '[hooks]' >> .hg/hgrc
  $ echo 'prechangegroup = sleep 5' >> .hg/hgrc

start a pull...

  $ hg pull ../source1 > pull.out 2>&1 &

... and start another pull before the first one has finished

  $ sleep 1
  $ hg pull ../source2 2>/dev/null
  pulling from ../source2
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  (run 'hg heads' to see heads, 'hg merge' to merge)
  $ cat pull.out
  pulling from ../source1
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 10 changesets with 10 changes to 1 files
  (run 'hg update' to get a working copy)

see the result

  $ wait
  $ hg verify
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  1 files, 11 changesets, 11 total revisions

  $ cd ..