tests/test-i18n.t

run-tests: move diff generation into TestResult

TestResult is the thing that captures all our test results. It's logical
for diff viewing to be handled there and not inside Test.

While writing this patch, it was discovered that Test.fail() was
printing redundant test result output. This has been removed.

Arguments controlling diffs have been removed from Test.__init__.

Translations are optional:

  $ "$TESTDIR/hghave" gettext || exit 80

#if no-outer-repo

Test that translations are compiled and installed correctly.

Default encoding in tests is "ascii" and the translation is encoded
using the "replace" error handler:

  $ LANGUAGE=pt_BR hg tip
  abortado: n?o foi encontrado um reposit?rio em '$TESTTMP' (.hg n?o encontrado)!
  [255]

Using a more accommodating encoding:

  $ HGENCODING=UTF-8 LANGUAGE=pt_BR hg tip
  abortado: n\xc3\xa3o foi encontrado um reposit\xc3\xb3rio em '$TESTTMP' (.hg n\xc3\xa3o encontrado)! (esc)
  [255]

Different encoding:

  $ HGENCODING=Latin-1 LANGUAGE=pt_BR hg tip
  abortado: n\xe3o foi encontrado um reposit\xf3rio em '$TESTTMP' (.hg n\xe3o encontrado)! (esc)
  [255]

#endif

Test keyword search in translated help text:

  $ HGENCODING=UTF-8 LANGUAGE=de hg help -k blättern
  Themen:
  
   extensions Benutzung erweiterter Funktionen
  
  Erweiterungen:
  
   pager Verwendet einen externen Pager zum Bl\xc3\xa4ttern in der Ausgabe von Befehlen (esc)

Check Mercurial specific translation problems in each *.po files, and
tool itself by doctest

  $ cd "$TESTDIR"/../i18n
  $ python check-translation.py *.po
  $ python check-translation.py --doctest
  $ cd $TESTTMP