jashkenas--coffeescript/test/scope.coffee

106 lines
2.0 KiB
CoffeeScript

# Scope
# -----
# * Variable Safety
# * Variable Shadowing
# * Auto-closure (`do`)
# * Global Scope Leaks
test "reference `arguments` inside of functions", ->
sumOfArgs = ->
sum = (a,b) -> a + b
sum = 0
sum += num for num in arguments
sum
eq 10, sumOfArgs(0, 1, 2, 3, 4)
test "assignment to an Object.prototype-named variable should not leak to outer scope", ->
# FIXME: fails on IE
(->
constructor = 'word'
)()
ok constructor isnt 'word'
test "siblings of splat parameters shouldn't leak to surrounding scope", ->
x = 10
oops = (x, args...) ->
oops(20, 1, 2, 3)
eq x, 10
test "catch statements should introduce their argument to scope", ->
try throw ''
catch e
do -> e = 5
eq 5, e
class Array then slice: fail # needs to be global
class Object then hasOwnProperty: fail
test "#1973: redefining Array/Object constructors shouldn't confuse __X helpers", ->
arr = [1..4]
arrayEq [3, 4], arr[2..]
obj = {arr}
for own k of obj
eq arr, obj[k]
test "#2255: global leak with splatted @-params", ->
ok not x?
arrayEq [0], ((@x...) -> @x).call {}, 0
ok not x?
test "#1183: super + fat arrows", ->
dolater = (cb) -> cb()
class A
constructor: ->
@_i = 0
foo : (cb) ->
dolater =>
@_i += 1
cb()
class B extends A
constructor : ->
super
foo : (cb) ->
dolater =>
dolater =>
@_i += 2
super cb
b = new B
b.foo => eq b._i, 3
test "#1183: super + wrap", ->
class A
m : -> 10
class B extends A
constructor : -> super
B::m = -> r = try super()
eq (new B).m(), 10
test "#1183: super + closures", ->
class A
constructor: ->
@i = 10
foo : -> @i
class B extends A
foo : ->
ret = switch 1
when 0 then 0
when 1 then super()
ret
eq (new B).foo(), 10
test "#2331: bound super regression", ->
class A
@value = 'A'
method: -> @constructor.value
class B extends A
method: => super
eq (new B).method(), 'A'