view tests/test-issue619.t @ 44261:04a3ae7aba14

chg: force-set LC_CTYPE on server start to actual value from the environment

Python 3.7+ will "coerce" the LC_CTYPE variable in many instances, and this can
cause issues with chg being able to start up. D7550 attempted to fix this, but a
combination of a misreading of the way that python3.7 does the coercion and an
untested state (LC_CTYPE being set to an invalid value) meant that this was
still not quite working.

This change will cause differences between chg and hg: hg will have the LC_CTYPE
environment variable coerced, while chg will not. This is unlikely to cause any
detectable behavior differences in what Mercurial itself outputs, but it does
have two known effects:

-   When using hg, the coerced LC_CTYPE will be passed to subprocesses, even
    non-python ones. Using chg will remove the coercion, and this will not
    happen. This is arguably more correct behavior on chg's part.
-   On macOS, if you set your region to Brazil but your language to English,
    this isn't representable in locale strings, so macOS sets LC_CTYPE=UTF-8. If
    this value is passed along when ssh'ing to a non-macOS machine, some
    functions (such as locale.setlocale()) may raise an exception due to an
    unsupported locale setting. This is most easily encountered when doing an
    interactive commit/split/etc. when using ui.interface=curses.

Differential Revision: https://phab.mercurial-scm.org/D8039

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]