Skip to content

Commit

Permalink
Triangle: Update tests to check properties, not types (#424)
Browse files Browse the repository at this point in the history 
* Triangle: Update tests to check properties, not types

As discussed here: #379

Converts the tests so that they are checking the property of a triangle
and not its type (or type stand-in like symbol/atom/etc.).

I've removed some duplicative tests, but I believe I've still covered
all the edge cases that were part of the old test suite.
  • Loading branch information
@IanWhitney
IanWhitney authored Oct 26, 2016
1 parent 79d01f2 commit b806246
Showing 1 changed file with 81 additions and 54 deletions.
135 changes: 81 additions & 54 deletions exercises/triangle/canonical-data.json
View file
Original file line number Diff line number Diff line change
Expand Up @@ -8,88 +8,115 @@
"They're degenerate triangles with all three vertices collinear.",
"(In contrast, we will test (0, 0, 0, Illegal), as it is a point).",

"The expectation are given as strings,",
"but your language may use the appropriate representations.",
"For example, enums, variants, or tagged unions all are viable candidates.",
"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",

"Your track may choose to have the 'illegal' result be another member of the enum/variant/union/etc.,",
"or instead to signal an error/exception/etc. on an illegal triangle.",

"If appropriate for your track, you'll need to ensure that no pair of expected values are equal.",
"Otherwise, an implementation that always returns a constant value may falsely pass the tests.",
"See https://github.com/exercism/xgo/pull/208"
"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": [
"equilateral": {
"description": "returns true if the triangle is equilateral",
"cases": [
{
"description": "equilateral triangle has all sides equal",
"sides": [2, 2, 2],
"expected": "equilateral"
"description": "true if all sides are equal",
"sides": [2, 2, 2],
"expected": true
},
{
"description": "larger equilateral triangle",
"sides": [10, 10, 10],
"expected": "equilateral"
"description": "false if any side is unequal",
"sides": [2, 3, 2],
"expected": false
},
{
"description": "isosceles triangle with last two sides equal",
"sides": [3, 4, 4],
"expected": "isosceles"
"description": "false if no sides are equal",
"sides": [5, 4, 6],
"expected": false
},
{
"description": "isosceles triangle with first two sides equal",
"sides": [4, 4, 3],
"expected": "isosceles"
"description": "All zero sides are illegal, so the triangle is not equilateral",
"sides": [0, 0, 0],
"expected": false
},
{
"description": "isosceles triangle with first and last sides equal",
"sides": [4, 3, 4],
"expected": "isosceles"
"#": "Your track may choose to skip this test and deal only with integers if appropriate",
"description": "sides may be floats",
"sides": [0.5, 0.5, 0.5],
"expected": true
}
]
},
"isosceles": {
"description": "returns true if the triangle is isosceles",
"cases": [
{
"description": "true if last two sides are equal",
"sides": [3, 4, 4],
"expected": true
},
{
"description": "isosceles triangle with unequal side larger than equal sides",
"sides": [4, 7, 4],
"expected": "isosceles"
"description": "true if first two sides are equal",
"sides": [4, 4, 3],
"expected": true
},
{
"description": "scalene triangle has no equal sides",
"sides": [3, 4, 5],
"expected": "scalene"
"description": "true if first and last sides are equal",
"sides": [4, 3, 4],
"expected": true
},
{
"description": "2a == b+c looks like equilateral, but isn't always",
"sides": [5, 4, 6],
"expected": "scalene"
"description": "equilateral triangles are also isosceles",
"sides": [4, 4, 4],
"expected": true
},
{
"description": "larger scalene triangle",
"sides": [10, 11, 12],
"expected": "scalene"
"description": "false if no sides are equal",
"sides": [2, 3, 4],
"expected": false
},
{
"description": "scalene triangle with sides in descending order",
"sides": [5, 4, 2],
"expected": "scalene"
"description": "Sides that violate triangle inequality are not isosceles, even if two are equal",
"sides": [1, 1, 3],
"expected": false
},
{
"#": "Your track may choose to skip this test and deal only with integers if appropriate",
"description": "sides may be floats",
"sides": [0.5, 0.4, 0.5],
"expected": true
}
]
},
"scalene": {
"description": "returns true if the triangle is scalene",
"cases": [
{
"description": "true if no sides are equal",
"sides": [5, 4, 6],
"expected": true
},
{
"#": "Your track may choose to skip this test and deal only with integers if appropriate",
"description": "small scalene triangle with floating point values",
"sides": [0.4, 0.6, 0.3],
"expected": "scalene"
"description": "false if all sides are equal",
"sides": [4, 4, 4],
"expected": false
},
{
"description": "a triangle violating the triangle inequality is illegal",
"sides": [7, 3, 2],
"expected": "illegal"
"description": "false if two sides are equal",
"sides": [4, 4, 3],
"expected": false
},
{
"description": "two sides equal, but still violates triangle inequality",
"sides": [1, 1, 3],
"expected": "illegal"
"description": "Sides that violate triangle inequality are not scalene, even if they are all different",
"sides": [7, 3, 2],
"expected": false
},
{
"description": "triangles with all sides zero are illegal",
"sides": [0, 0, 0],
"expected": "illegal"
"#": "Your track may choose to skip this test and deal only with integers if appropriate",
"description": "sides may be floats",
"sides": [0.5, 0.4, 0.6],
"expected": true
}
]
]
}
}

0 comments on commit b806246

Please sign in to comment.