python/triangle/triangle_test.py

from triangle import Triangle, TriangleError
import unittest


class TriangleTests(unittest.TestCase):
    def test_equilateral_triangles_have_equal_sides(self):
        self.assertEqual("equilateral", Triangle(2, 2, 2).kind())

    def test_larger_equilateral_triangles_also_have_equal_sides(self):
        self.assertEqual("equilateral", Triangle(10, 10, 10).kind())

    def test_isosceles_triangles_have_last_two_sides_equal(self):
        self.assertEqual("isosceles", Triangle(3, 4, 4).kind())

    def test_isosceles_triangles_have_first_and_last_sides_equal(self):
        self.assertEqual("isosceles", Triangle(4, 3, 4).kind())

    def test_isosceles_triangles_have_two_first_sides_equal(self):
        self.assertEqual("isosceles", Triangle(4, 4, 3).kind())

    def test_isosceles_triangles_have_in_fact_exactly_two_sides_equal(self):
        self.assertEqual("isosceles", Triangle(10, 10, 2).kind())

    def test_scalene_triangles_have_no_equal_sides(self):
        self.assertEqual("scalene", Triangle(3, 4, 5).kind())

    def test_scalene_triangles_have_no_equal_sides_at_a_larger_scale_too(self):
        self.assertEqual("scalene", Triangle(10, 11, 12).kind())

        self.assertEqual("scalene", Triangle(5, 4, 2).kind())

    def test_very_small_triangles_are_legal(self):
        self.assertEqual("scalene", Triangle(0.4, 0.6, 0.3).kind())

    def test_triangles_with_no_size_are_illegal(self):
        self.assertRaises(
            TriangleError,
            Triangle, 0, 0, 0
        )

    def test_triangles_with_negative_sides_are_illegal(self):
        self.assertRaises(
            TriangleError,
            Triangle, 3, 4, -5
        )

    def test_triangles_violating_triangle_inequality_are_illegal(self):
        self.assertRaises(
            TriangleError,
            Triangle, 1, 1, 3
        )

    def test_triangles_violating_triangle_inequality_are_illegal_2(self):
        self.assertRaises(
            TriangleError,
            Triangle, 2, 4, 2
        )

    def test_triangles_violating_triangle_inequality_are_illegal_3(self):
        self.assertRaises(
            TriangleError,
            Triangle, 7, 3, 2
        )

if __name__ == '__main__':
    unittest.main()