def test_commutative_case(segments_pair: SegmentsPair) -> None:
first, second = segments_pair
result = subtract_segments(first, second)
assert equivalence(result == subtract_segments(second, first),
first == second)
def test_intersection_minuend(segments_triplet: SegmentsTriplet) -> None:
first, second, third = segments_triplet
first_second_intersection = intersect_segments(first, second)
second_third_difference = subtract_segments(second, third)
assert (not is_segment(first_second_intersection)
or not is_segment(second_third_difference)
or are_compounds_similar(
subtract_segments(first_second_intersection, third),
intersect_segments(first, second_third_difference)))
def test_difference_operand(segments_triplet: SegmentsTriplet) -> None:
first, second, third = segments_triplet
first_second_difference = subtract_segments(first, second)
first_third_union = unite_segments(first, third)
second_third_difference = subtract_segments(second, third)
assert (not is_segment(first_second_difference)
or not is_segment(first_third_union)
or not is_segment(second_third_difference)
or are_compounds_similar(
unite_segments(first_second_difference, third),
subtract_segments(first_third_union, second_third_difference)))
def test_reversals(segments_pair: SegmentsPair) -> None:
first, second = segments_pair
result = subtract_segments(first, second)
assert are_compounds_similar(
result, subtract_segments(reverse_segment(first), second))
assert result == subtract_segments(first, reverse_segment(second))
assert are_compounds_similar(
result,
reverse_compound_coordinates(
subtract_segments(reverse_segment_coordinates(first),
reverse_segment_coordinates(second))))
def test_difference_subtrahend(segments_triplet: SegmentsTriplet) -> None:
first, second, third = segments_triplet
first_second_difference = subtract_segments(first, second)
first_third_difference = intersect_segments(first, third)
second_third_difference = subtract_segments(second, third)
assert (not is_segment(first_second_difference)
or not is_segment(first_third_difference)
or not is_segment(second_third_difference)
or are_compounds_similar(
subtract_segments(first, second_third_difference),
unite_segments(first_second_difference,
first_third_difference)))
def test_equivalents(segments_pair: SegmentsPair) -> None:
first, second = segments_pair
result = symmetric_subtract_segments(first, second)
first_second_difference = subtract_segments(first, second)
first_second_union = unite_segments(first, second)
second_first_difference = subtract_segments(second, first)
second_first_intersection = intersect_segments(second, first)
assert (not is_segment(second_first_intersection)
or not is_segment(first_second_union) or are_compounds_similar(
result,
subtract_segments(first_second_union,
second_first_intersection)))
assert (not is_segment(first_second_difference)
or not is_segment(second_first_difference)
or are_compounds_similar(
result,
unite_segments(first_second_difference,
second_first_difference)))
def __sub__(self, other: Compound[Coordinate]) -> Compound[Coordinate]:
"""
Returns difference of the segment with the other geometry.
Time complexity:
``O(1)``
Memory complexity:
``O(1)``
>>> from gon.base import EMPTY, Point, Segment
>>> segment = Segment(Point(0, 0), Point(2, 0))
>>> segment - segment is EMPTY
True
"""
return (self if isinstance(other, Multipoint) else
(subtract_segments(self, other, context=self._context)
if isinstance(other, Segment) else NotImplemented))
def test_basic(segments_pair: SegmentsPair) -> None:
first, second = segments_pair
result = subtract_segments(first, second)
assert is_maybe_linear(result)