{
  "exercise": "triangle",
  "version": "1.0.0",
  "comments": [
    " Pursuant to discussion in #202, we have decided NOT to test triangles ",
    " where all side lengths are positive but a + b = c. e.g:               ",
    " (2, 4, 2, Isosceles), (1, 3, 4, Scalene).                             ",
    " It's true that the triangle inequality admits such triangles.These    ",
    " triangles have zero area, however.                                    ",
    " They're degenerate triangles with all three vertices collinear.       ",
    " (In contrast, we will test (0, 0, 0, Illegal), as it is a point)      ",
    " The tests assert properities of the triangle are true or false.       ",
    " See: https://github.com/exercism/x-common/issues/379 for disscussion  ",
    " of this approach                                                      ",
    " How you handle invalid triangles is up to you. These tests suggest a  ",
    " triangle is returned, but all of its properties are false. But you    ",
    " could also have the creation of an invalid triangle return an error   ",
    " or exception. Choose what is idiomatic for your language.             "
  ],
  "cases": [
    {
      "description": "returns true if the triangle is equilateral",
      "cases": [
        {
          "description": "true if all sides are equal",
          "property": "equilateral",
          "sides": [2, 2, 2],
          "expected": true
        },
        {
          "description": "false if any side is unequal",
          "property": "equilateral",
          "sides": [2, 3, 2],
          "expected": false
        },
        {
          "description": "false if no sides are equal",
          "property": "equilateral",
          "sides": [5, 4, 6],
          "expected": false
        },
        {
          "description": "All zero sides are illegal, so the triangle is not equilateral",
          "property": "equilateral",
          "sides": [0, 0, 0],
          "expected": false
        },
        {
          "comments": [
            " Your track may choose to skip this test    ",
            " and deal only with integers if appropriate "
          ],
          "description": "sides may be floats",
          "property": "equilateral",
          "sides": [0.5, 0.5, 0.5],
          "expected": true
        }
      ]
    },
    {
      "description": "returns true if the triangle is isosceles",
      "cases": [
        {
          "description": "true if last two sides are equal",
          "property": "isosceles",
          "sides": [3, 4, 4],
          "expected": true
        },
        {
          "description": "true if first two sides are equal",
          "property": "isosceles",
          "sides": [4, 4, 3],
          "expected": true
        },
        {
          "description": "true if first and last sides are equal",
          "property": "isosceles",
          "sides": [4, 3, 4],
          "expected": true
        },
        {
          "description": "equilateral triangles are also isosceles",
          "property": "isosceles",
          "sides": [4, 4, 4],
          "expected": true
        },
        {
          "description": "false if no sides are equal",
          "property": "isosceles",
          "sides": [2, 3, 4],
          "expected": false
        },
        {
          "description": "Sides that violate triangle inequality are not isosceles, even if two are equal",
          "property": "isosceles",
          "sides": [1, 1, 3],
          "expected": false
        },
        {
          "comments": [
            " Your track may choose to skip this test    ",
            " and deal only with integers if appropriate "
          ],
          "property": "isosceles",
          "description": "sides may be floats",
          "sides": [0.5, 0.4, 0.5],
          "expected": true
        }
      ]
    },
    {
      "description": "returns true if the triangle is scalene",
      "cases": [
        {
          "description": "true if no sides are equal",
          "property": "scalene",
          "sides": [5, 4, 6],
          "expected": true
        },
        {
          "description": "false if all sides are equal",
          "property": "scalene",
          "sides": [4, 4, 4],
          "expected": false
        },
        {
          "description": "false if two sides are equal",
          "property": "scalene",
          "sides": [4, 4, 3],
          "expected": false
        },
        {
          "description": "Sides that violate triangle inequality are not scalene, even if they are all different",
          "property": "scalene",
          "sides": [7, 3, 2],
          "expected": false
        },
        {
          "comments": [
            " Your track may choose to skip this test    ",
            " and deal only with integers if appropriate "
          ],
          "description": "sides may be floats",
          "property": "scalene",
          "sides": [0.5, 0.4, 0.6],
          "expected": true
        }
      ]
    }
  ]
}