'Migrations might introduce translated revisions without based_on
set. Tolerate these.
If based_on of a translation\'s current_revision is None, the
translation should be considered out of date iff any
major-significance, approved revision to the English article exists.'

def test_majorly_outdated_with_unapproved_parents(self):

    parent_rev = RevisionFactory()
    trans = DocumentFactory(parent=parent_rev.document, locale='de')
    trans_rev = RevisionFactory(document=trans, is_approved=True)
    assert (trans_rev.based_on is None), "based_on    defaulted    to    something    non-None,    which    this    test    wasn't    expecting."
    assert (not trans.is_majorly_outdated()), 'A    translation    was    considered    majorly    out    of    date    even    though    the    English    document    has    never    had    an    approved    revision    of    major    significance.'
    ApprovedRevisionFactory(document=parent_rev.document, significance=MAJOR_SIGNIFICANCE, is_ready_for_localization=True)
    assert trans.is_majorly_outdated(), "A    translation    was    not    considered    majorly    outdated    when    its    current    revision's    based_on    value    was    None."
