view tests/test-cache-abuse.t @ 45584:4c8a93ec6908

merge: store commitinfo if these is a dc or cd conflict

delete-changed or changed-delete conflicts can either be resolved by mergetool,
if some tool is passed and using or by user choose something on prompt or user
doing some `hg revert` after choosing the file to remain conflicted.

If the user decides to keep the changed side, on commit we just reuse the parent
filenode. This is mostly fine unless we are in a distributed environment and
people are doing criss-cross merges.

Since, we don't have recursive merges or any other way of describing the end
result of the merge was an explicit choice and it should be differentiated from
it's ancestors, merge algo during criss-cross merges fails to take in account
the explicit choice made by user and end up with a what-can-be-said-wrong-merge.

The solution which we are trying to fix this is by creating a filenode on commit
instead of reusing the parent filenode. This helps differentiate between
pre-merged filenode and post-merge filenode and kind of tells about the choice
user made.

To implement creating new filenode functionality, we store info about these
files in mergestate so that we can read them on commit and force create a new
filenode.

Differential Revision: https://phab.mercurial-scm.org/D8988

Enable obsolete markers

  $ cat >> $HGRCPATH << EOF
  > [experimental]
  > evolution.createmarkers=True
  > [phases]
  > publish=False
  > EOF

Build a repo with some cacheable bits:

  $ hg init a
  $ cd a

  $ echo a > a
  $ hg ci -qAm0
  $ hg tag t1
  $ hg book -i bk1

  $ hg branch -q b2
  $ hg ci -Am1
  $ hg tag t2

  $ echo dumb > dumb
  $ hg ci -qAmdumb
  $ hg debugobsolete b1174d11b69e63cb0c5726621a43c859f0858d7f
  1 new obsolescence markers
  obsoleted 1 changesets

  $ hg phase -pr t1
  $ hg phase -fsr t2

Make a helper function to check cache damage invariants:

- command output shouldn't change
- cache should be present after first use
- corruption/repair should be silent (no exceptions or warnings)
- cache should survive deletion, overwrite, and append
- unreadable / unwriteable caches should be ignored
- cache should be rebuilt after corruption

  $ damage() {
  >  CMD=$1
  >  CACHE=.hg/cache/$2
  >  CLEAN=$3
  >  hg $CMD > before
  >  test -f $CACHE || echo "not present"
  >  echo bad > $CACHE
  >  test -z "$CLEAN" || $CLEAN
  >  hg $CMD > after
  >  "$RUNTESTDIR/pdiff" before after || echo "*** overwrite corruption"
  >  echo corruption >> $CACHE
  >  test -z "$CLEAN" || $CLEAN
  >  hg $CMD > after
  >  "$RUNTESTDIR/pdiff" before after || echo "*** append corruption"
  >  rm $CACHE
  >  mkdir $CACHE
  >  test -z "$CLEAN" || $CLEAN
  >  hg $CMD > after
  >  "$RUNTESTDIR/pdiff" before after || echo "*** read-only corruption"
  >  test -d $CACHE || echo "*** directory clobbered"
  >  rmdir $CACHE
  >  test -z "$CLEAN" || $CLEAN
  >  hg $CMD > after
  >  "$RUNTESTDIR/pdiff" before after || echo "*** missing corruption"
  >  test -f $CACHE || echo "not rebuilt"
  > }

Beat up tags caches:

  $ damage "tags --hidden" tags2
  $ damage tags tags2-visible
  $ damage "tag -f t3" hgtagsfnodes1
  1 new orphan changesets
  1 new orphan changesets
  1 new orphan changesets
  1 new orphan changesets
  1 new orphan changesets

Beat up branch caches:

  $ damage branches branch2-base "rm .hg/cache/branch2-[vs]*"
  $ damage branches branch2-served "rm .hg/cache/branch2-[bv]*"
  $ damage branches branch2-visible
  $ damage "log -r branch(.)" rbc-names-v1
  $ damage "log -r branch(default)" rbc-names-v1
  $ damage "log -r branch(b2)" rbc-revs-v1

We currently can't detect an rbc cache with unknown names:

  $ damage "log -qr branch(b2)" rbc-names-v1
  --- before	* (glob)
  +++ after	* (glob)
  @@ -1,8 +?,0 @@ (glob)
  -2:5fb7d38b9dc4
  -3:60b597ffdafa
  -4:b1174d11b69e
  -5:6354685872c0
  -6:5ebc725f1bef
  -7:7b76eec2f273
  -8:ef3428d9d644
  -9:ba7a936bc03c
  *** append corruption