tests/test-journal-exists.t

fileset: use decorator to mark a function as fileset predicate

Using decorator can localize changes for adding (or removing) a
fileset predicate function in source code.

It is also useful to pick predicates up for specific purpose. For
example, subsequent patches marks predicates as "call status" or "use
existing" via decorator.

To avoid (1) redundancy between "predicate name" and (the beginning
of) help document, and (2) accidental typo of help document, this
patch also makes decorator put predicate declration into the beginning
of help.

  $ hg init
  $ echo a > a
  $ hg ci -Am0
  adding a

  $ hg -q clone . foo

  $ touch .hg/store/journal

  $ echo foo > a
  $ hg ci -Am0
  abort: abandoned transaction found!
  (run 'hg recover' to clean up transaction)
  [255]

  $ hg recover
  rolling back interrupted transaction
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  1 files, 1 changesets, 1 total revisions

Check that zero-size journals are correctly aborted:

#if unix-permissions no-root
  $ hg bundle -qa repo.hg
  $ chmod -w foo/.hg/store/00changelog.i

  $ hg -R foo unbundle repo.hg
  adding changesets
  abort: Permission denied: $TESTTMP/foo/.hg/store/.00changelog.i-* (glob)
  [255]

  $ if test -f foo/.hg/store/journal; then echo 'journal exists :-('; fi
#endif