view tests/test-hooklib-reject_new_heads.t @ 49991:3997c64eff8b

test: use a more direct approach to test racy mutation

The previous test was relying on implementation details and harder to maintain.

The new version is closer to the initial intend : "What happens the file get overwritten from under the current process"

This change is motivated by further changes around the transaction and dirstate
logic that would break the fragile equilibrium that existed before this patch.

Making this change early make it easier to review on its own and remove noise
in future larger changes.

  $ cat <<EOF >> $HGRCPATH
  > [extensions]
  > hooklib =
  > 
  > [phases]
  > publish = False
  > EOF
  $ hg init a
  $ hg --cwd a debugbuilddag '.:parent.*parent'
  $ hg --cwd a log -G
  o  changeset:   2:fa942426a6fd
  |  tag:         tip
  |  parent:      0:1ea73414a91b
  |  user:        debugbuilddag
  |  date:        Thu Jan 01 00:00:02 1970 +0000
  |  summary:     r2
  |
  | o  changeset:   1:66f7d451a68b
  |/   user:        debugbuilddag
  |    date:        Thu Jan 01 00:00:01 1970 +0000
  |    summary:     r1
  |
  o  changeset:   0:1ea73414a91b
     tag:         parent
     user:        debugbuilddag
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     r0
  
  $ hg init b
  $ cat <<EOF >> b/.hg/hgrc
  > [hooks]
  > pretxnclose.reject_new_heads = \
  >   python:hgext.hooklib.reject_new_heads.hook
  > EOF
  $ hg --cwd b pull ../a
  pulling from ../a
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  error: pretxnclose.reject_new_heads hook failed: Changes on branch 'default' resulted in multiple heads
  transaction abort!
  rollback completed
  abort: Changes on branch 'default' resulted in multiple heads
  [255]
  $ hg --cwd b pull ../a -r 1ea73414a91b
  pulling from ../a
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 0 changes to 0 files
  new changesets 1ea73414a91b (1 drafts)
  (run 'hg update' to get a working copy)