evolve: remove the unnecessary condition to check empty successors set
I annotated the history of this "newer == [()]" condition and found
that it was added in the initial stages of evolution project (more than
8 years ago) and there is no test where we get [()] as a successor set.
So looks like "if not newer" is enough to check if it is empty.
I also looked into obsutil.successorssets() implementation and
I don't think it would give us [()] in any case.
[flake8]
ignore =
#closing bracket does not match indentation of opening bracket's line
E123,
# closing bracket does not match visual indentation
E124,
# visually indented line with same indent as next logical line
E129,
# at least two spaces before inline comment
E261,
# too many leading '#' for block comment
E266,
# expected 2 blank lines, found 0
E302,
# expected 2 blank lines after end of function or class
E305,
# module level import not at top of file
E402,
# line too long (82 > 79 characters)
E501,
# do not assign a lambda expression, use a def
E731,
# class names should use CapWords convention
N801,
# line break occurred before a binary operator
W503
builtins=xrange, execfile