view tests/test-issue619.t @ 29494:3b5389ef5cfe

perf: define util.safehasattr forcibly for Mercurial earlier than 1.9.3

Before this patch, using util.safehasattr() prevents perf.py from
being loaded by Mercurial earlier than 1.9.3 (or 94b200a11cf7),
because util.safehasattr() isn't available in such Mercurial, even
though there are some code paths for Mercurial earlier than 1.9.3.

For example, setting "_prereadsize" attribute in perfindex() and
perfnodelookup() is effective only with Mercurial earlier than 1.8 (or
61c9bc3da402).

This patch is a preparation for using util.safehasattr() safely in
subsequent patches.

This patch defines util.safehasattr() forcibly without examining
whether it is available or not, because:

  - examining existence of "safehasattr" safely itself needs similar logic
  - safehasattr() is small enough to define locally

https://bz.mercurial-scm.org/619

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

  $ echo b > b
  $ hg branch b
  marked working directory as branch b
  (branches are permanent and global, did you want a bookmark?)
  $ hg ci -Amb
  adding b

  $ hg co -C 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved

Fast-forward:

  $ hg merge b
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -Ammerge

Bogus fast-forward should fail:

  $ hg merge b
  abort: merging with a working directory ancestor has no effect
  [255]

Even with strange revset (issue4465)

  $ hg merge ::.
  abort: merging with a working directory ancestor has no effect
  [255]