tests/test-merge-subrepos.t

color: set _colormode to None when mode is unset (issue3895)

Previously, colorui assumed that it would only be called when mode wasn't
None. 7ae12ce87594 changed that, so now colorui needs to care about whether it
should colorize output.

  $ hg init

  $ echo a > a
  $ hg ci -qAm 'add a'

  $ hg init subrepo
  $ echo 'subrepo = http://example.net/libfoo' > .hgsub
  $ hg ci -qAm 'added subrepo'

  $ hg up -qC 0
  $ echo ax > a
  $ hg ci -m 'changed a'
  created new head

  $ hg up -qC 1
  $ cd subrepo
  $ echo b > b
  $ hg add b
  $ cd ..

Should fail, since there are added files to subrepo:

  $ hg merge
  abort: outstanding uncommitted changes in subrepository 'subrepo'
  [255]