view tests/test-merge6.t @ 23971:6becb9dbca25 stable

merge: mark .hgsubstate as possibly dirty before submerge for consistency

Before this patch, failure of updating subrepos may cause inconsistent
".hgsubstate". For example:

  1. dirstate entry for ".hgsubstate" of the parent repo is filled
     with valid size/date (via "hg state" or so)

  2. "hg update" is invoked at the parent repo

  3. ".hgsubstate" of the parent repo is updated on the filesystem as
     a part of "g"(et) action in "merge.applyupdates"

  4. it is assumed that size/date of ".hgsubstate" on the filesystem
     aren't changed from ones at (1)

     this is not so difficult condition, because just changing hash
     ids (every ids are same in length) in ".hgsubstate" doesn't
     change the file size of it

  5. "subrepo.submerge()" is invoked to update subrepos

  6. failure of updating in one of subrepos raises exception
     (e.g. "untracked file differs")

  7. "hg update" is aborted without updating dirstate of the parent repo

     dirstate entry for ".hgsubstate" still holds size/date at (1)

Then, ".hgsubstate" of the parent repo is treated as "CLEAN"
unexpectedly, because updating ".hgsubstate" at (3) doesn't change
size/date of it on the filesystem: see assumption at (4).

This inconsistent ".hgsubstate" status causes unexpected behavior, for
example:

  - "hg revert" forgets to revert ".hgsubstate"

  - "hg update" misunderstands that (not yet updated) subrepos diverge
    (then, it shows the prompt to confirm user's decision)

To avoid inconsistent ".hgsubstate" status above, this patch marks
".hgsubstate" as possibly dirty before "submerge" invocation.
"normallookup"-ed (= dirty) dirstate should be written out, even if
processing is aborted by failure.

This patch marks ".hgsubstate" as possibly dirty before "submerge",
also when it is removed or merged while merging, for safety. This
should prevent Mercurial from misunderstanding inconsistent
".hgsubstate" as clean.

To satisfy conditions at (1) and (4) above, this patch uses "hg status
--config debug.dirstate.delaywrite=2" (to fill valid size/date into
dirstate) and "touch" (to fix date of the file).

  $ cat <<EOF > merge
  > import sys, os
  > print "merging for", os.path.basename(sys.argv[1])
  > EOF
  $ HGMERGE="python ../merge"; export HGMERGE

  $ hg init A1
  $ cd A1
  $ echo This is file foo1 > foo
  $ echo This is file bar1 > bar
  $ hg add foo bar
  $ hg commit -m "commit text"

  $ cd ..
  $ hg clone A1 B1
  updating to branch default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ cd A1
  $ rm bar
  $ hg remove bar
  $ hg commit -m "commit test"

  $ cd ../B1
  $ echo This is file foo22 > foo
  $ hg commit -m "commit test"

  $ cd ..
  $ hg clone A1 A2
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg clone B1 B2
  updating to branch default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ cd A1
  $ hg pull ../B1
  pulling from ../B1
  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)
  $ hg merge
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg commit -m "commit test"
bar should remain deleted.
  $ hg manifest --debug
  f9b0e817f6a48de3564c6b2957687c5e7297c5a0 644   foo

  $ cd ../B2
  $ hg pull ../A2
  pulling from ../A2
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 0 changes to 0 files (+1 heads)
  (run 'hg heads' to see heads, 'hg merge' to merge)
  $ hg merge
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg commit -m "commit test"
bar should remain deleted.
  $ hg manifest --debug
  f9b0e817f6a48de3564c6b2957687c5e7297c5a0 644   foo

  $ cd ..