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105 lines
2.5 KiB
CoffeeScript
105 lines
2.5 KiB
CoffeeScript
# Helpers
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# -------
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# pull the helpers from `CoffeeScript.helpers` into local variables
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{starts, ends, repeat, compact, count, merge, extend, flatten, del, last} = CoffeeScript.helpers
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# `starts`
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test "the `starts` helper tests if a string starts with another string", ->
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ok starts('01234', '012')
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ok not starts('01234', '123')
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test "the `starts` helper can take an optional offset", ->
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ok starts('01234', '34', 3)
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ok not starts('01234', '01', 1)
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# `ends`
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test "the `ends` helper tests if a string ends with another string", ->
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ok ends('01234', '234')
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ok not ends('01234', '012')
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test "the `ends` helper can take an optional offset", ->
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ok ends('01234', '012', 2)
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ok not ends('01234', '234', 6)
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# `repeat`
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test "the `repeat` helper concatenates a given number of times", ->
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eq 'asdasdasd', repeat('asd', 3)
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test "`repeat`ing a string 0 times always returns the empty string", ->
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eq '', repeat('whatever', 0)
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# `compact`
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test "the `compact` helper removes falsey values from an array, preserves truthy ones", ->
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allValues = [1, 0, false, obj={}, [], '', ' ', -1, null, undefined, true]
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truthyValues = [1, obj, [], ' ', -1, true]
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arrayEq truthyValues, compact(allValues)
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# `count`
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test "the `count` helper counts the number of occurances of a string in another string", ->
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eq 1/0, count('abc', '')
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eq 0, count('abc', 'z')
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eq 1, count('abc', 'a')
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eq 1, count('abc', 'b')
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eq 2, count('abcdc', 'c')
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eq 2, count('abcdabcd','abc')
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# `merge`
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test "the `merge` helper makes a new object with all properties of the objects given as its arguments", ->
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ary = [0, 1, 2, 3, 4]
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obj = {}
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merged = merge obj, ary
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ok merged isnt obj
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ok merged isnt ary
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for own key, val of ary
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eq val, merged[key]
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# `extend`
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test "the `extend` helper performs a shallow copy", ->
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ary = [0, 1, 2, 3]
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obj = {}
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# should return the object being extended
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eq obj, extend(obj, ary)
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# should copy the other object's properties as well (obviously)
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eq 2, obj[2]
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# `flatten`
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test "the `flatten` helper flattens an array", ->
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success = yes
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(success and= typeof n is 'number') for n in flatten [0, [[[1]], 2], 3, [4]]
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ok success
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# `del`
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test "the `del` helper deletes a property from an object and returns the deleted value", ->
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obj = [0, 1, 2]
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eq 1, del(obj, 1)
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ok 1 not of obj
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# `last`
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test "the `last` helper returns the last item of an array-like object", ->
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ary = [0, 1, 2, 3, 4]
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eq 4, last(ary)
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test "the `last` helper allows one to specify an optional offset", ->
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ary = [0, 1, 2, 3, 4]
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eq 2, last(ary, 2)
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