view tests/test-pull-pull-corruption.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)

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 ..