RxLua/tests/elementAt.lua
2016-10-15 10:31:23 -07:00

36 lines
1.3 KiB
Lua

describe('elementAt', function()
it('errors when its parent errors', function()
expect(Rx.Observable.throw():elementAt(1).subscribe).to.fail()
end)
it('chains subscriptions', function()
local subscription = Rx.Subscription.create()
local observable = Rx.Observable.create(function() return subscription end)
expect(observable:subscribe()).to.equal(subscription)
expect(observable:elementAt(1):subscribe()).to.equal(subscription)
end)
it('errors if no index is specified', function()
expect(Rx.Observable.of(1):elementAt().subscribe).to.fail()
end)
it('produces no values if the specified index is less than one', function()
expect(Rx.Observable.of(1):elementAt(0)).to.produce.nothing()
expect(Rx.Observable.of(1):elementAt(-1)).to.produce.nothing()
end)
it('produces no values if the specified index is greater than the number of elements produced by the source', function()
expect(Rx.Observable.of(1):elementAt(2)).to.produce.nothing()
end)
it('produces all values produced by the source at the specified index', function()
local observable = Rx.Observable.create(function(observer)
observer:onNext(1, 2, 3)
observer:onNext(4, 5, 6)
observer:onCompleted()
end)
expect(observable:elementAt(2)).to.produce({{4, 5, 6}})
end)
end)