Mirror: 🎩 A tiny but capable push & pull stream library for TypeScript and Flow
Merge pull request #11 from parkerziegler/test/add-switchMap-tests
Add tests for switchMap.
authored by
Phil Plückthun
and committed by
GitHub
f2b4a6dc
9ded31eb
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__tests__/wonka_test.re
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__tests__/wonka_test.re
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expect(res) |> toEqual([| Push(1), Push(2), Push(1), Push(2), End |]);
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});
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});
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describe("switchMap", () => {
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afterEach(() => Jest.useRealTimers());
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open Expect;
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open! Expect.Operators;
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it("maps from a source and switches to a new source", () => {
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let a = Wonka.fromList([1, 2, 3]);
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let talkback = ref((. _: Wonka_types.talkbackT) => ());
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let signals = [||];
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let source = Wonka.switchMap((.x) => Wonka.fromList([x * x]), a);
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source((.signal) =>
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switch (signal) {
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| Start(x) =>
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talkback := x;
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x(.Pull);
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| Push(_) =>
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ignore(Js.Array.push(signal, signals));
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talkback^(.Pull);
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| End => ignore(Js.Array.push(signal, signals))
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}
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);
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expect(signals) == [|Push(1), Push(4), Push(9), End|];
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});
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it("unsubscribes from previous subscriptions", () => {
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Jest.useFakeTimers();
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let a = Wonka.interval(100);
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let talkback = ref((._: Wonka_types.talkbackT) => ());
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let signals = [||];
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let source =
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Wonka.switchMap((._) => Wonka.interval(25), a) |> Wonka.take(5);
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source((.signal) =>
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switch (signal) {
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| Start(x) =>
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talkback := x;
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x(.Pull);
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| Push(_) =>
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ignore(Js.Array.push(signal, signals));
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talkback^(.Pull);
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| End => ignore(Js.Array.push(signal, signals))
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}
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);
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Jest.runTimersToTime(300);
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expect(signals)
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== [|Push(0), Push(1), Push(2), Push(0), Push(1), End|];
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});
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testPromise("follows the spec for listenables", () =>
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Wonka_thelpers.testWithListenable(source =>
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Wonka.switchMap((.x) => x, Wonka.fromList([source]))
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)
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|> Js.Promise.then_(x =>
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expect(x)
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|> toEqual(([|Pull, Pull, Pull|], [|Push(1), Push(2), End|]))
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|> Js.Promise.resolve
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)
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);
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testPromise(
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"ends itself and source when its talkback receives the End signal", () =>
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Wonka_thelpers.testTalkbackEnd(source =>
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Wonka.switchMap((.x) => x, Wonka.fromList([source]))
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)
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|> Js.Promise.then_(x =>
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expect(x)
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|> toEqual(([|Pull, Pull, Close|], [|Push(1)|]))
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|> Js.Promise.resolve
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)
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);
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});
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});
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describe("sink factories", () => {