python3Packages.blessed fails its test suite

[peti]

I get the following error trying to compile the Python library blessed. Unfortunately, this breaks GNU Mailman, which depends on this package. git blame identified b3ddab8 as the commit that caused this error:

=================================== FAILURES ===================================
___________________ test_nested_formattingstring_type_error ____________________

monkeypatch = <_pytest.monkeypatch.MonkeyPatch object at 0x7fffee5d0a50>

    def test_nested_formattingstring_type_error(monkeypatch):
        """Test formatters.FormattingString raising TypeError."""
        from blessed.formatters import FormattingString
    
        # given,
        pstr = FormattingString(u'a-', u'n-')
        expected_msg = (
            "Positional argument #1 is {0} expected any of "
            .format(type(1)))
    
        # exercise,
        with pytest.raises(TypeError) as err:
            pstr('text', 1, '...')
    
        # verify,
>       assert expected_msg in '{0}'.format(err)
E       assert "Positional argument #1 is <class 'int'> expected any of " in '<ExceptionInfo TypeError tblen=2>'
E        +  where '<ExceptionInfo TypeError tblen=2>' = <built-in method format of str object at 0x7fffee6b3130>(<ExceptionInfo TypeError tblen=2>)
E        +    where <built-in method format of str object at 0x7fffee6b3130> = '{0}'.format

blessed/tests/test_formatters.py:156: AssertionError
======================== 1 failed, 283 passed in 11.01s ========================

Ping: @FRidh

[peti]

Issue reported upstream: jquast/blessed#109