view tests/test-issue1102.t @ 39037:ede768cfe83e

mail: always fall back to iso-8859-1 if us-ascii won't work (BC)

It looks like this was a well-intentioned backwards compat hack for
previewing the output of `hg email` in a stable way. Unfortunately I
think this hack's time has come, because Python 3 does a much better
job of ensuring it actually emits *valid* email messages. In
particular, Python 2 would blindly trust us that the bytes we handed
it were valid for the encoding we claimed, but Python 3 has some more
sniff-tests that we end up failing.

As a result, if we're going to print an email to the terminal, try
us-ascii first, but if that fails go straight to iso-8859-1 which
should be reasonably readable for ascii-compatible patch bodies. This
*will* be a breaking change for ascii-incompatible textual patch
content, but I don't think that's avoidable if we want to continue
using the email library from the stdlib.

.. bc::

  Emails from the patchbomb extension will always be printed as though
  they are iso-8859-1 if they're not valid us-ascii. Previously,
  previewed emails were always claimed to be us-ascii and might
  contain invalid byte sequences.

Differential Revision: https://phab.mercurial-scm.org/D4231

  $ rm -rf a
  $ hg init a
  $ cd a
  $ echo a > a
  $ hg ci -Am0
  adding a
  $ hg tag t1 # 1
  $ hg tag --remove t1 # 2

  $ hg co 1
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg tag -f -r0 t1
  $ hg tags
  tip                                3:a49829c4fc11
  t1                                 0:f7b1eb17ad24

  $ cd ..