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import { createRoot, createSignal, from, observable } from "../src";
describe("Observable operator", () => {  test("to observable", () => {    let out: string;    let set: (v: string) => void;    createRoot(() => {      const [s, _set] = createSignal("Hi"),        obsv$ = observable(s);
      set = _set;      obsv$.subscribe({ next: v => (out = v) });    });    expect(out!).toBe("Hi");    set!("John");    expect(out!).toBe("John");  });
  test("preserve the observer's next binding", () => {    const observer = {      next: jest.fn().mockReturnThis()    };
    createRoot(() => {      const [s] = createSignal("Hi"),        obsv$ = observable(s);
      obsv$.subscribe(observer);    });    expect(observer.next).toHaveReturnedWith(observer);  });
  test("observable throws TypeError on non-object", () => {    const [s, _set] = createSignal("Hi");    const o = observable(s);    expect(() => o.subscribe(null as any)).toThrow(TypeError);  });
  test("observable unsubscribe", () => {    const [s, set] = createSignal("Hi");    const o = observable(s);    let out: string;    let subscription: any;    createRoot(() => {      subscription = o.subscribe({        next(v) {          out = v;        }      });    });    set("John");    expect(out!).toBe("John");    subscription.unsubscribe();    set("Benjamin");    expect(out!).toBe("John");  });});
describe("from transform", () => {  test("from subscribable", async () => {    let out: () => string | undefined;    let set: (v: string) => void;    createRoot(() => {      const [s, _set] = createSignal("Hi"),        obsv$ = observable(s);
      set = _set;      out = from(obsv$);    });    expect(out!()).toBe("Hi");    set!("John");    expect(out!()).toBe("John");  });
  test("from producer", async () => {    let out: () => string | undefined;    let set: (v: string) => void;    createRoot(() => {      const [s, _set] = createSignal("Hi"),        obsv$ = observable(s);
      set = _set;      out = from(set => {        const sub = obsv$.subscribe(set);        return () => sub.unsubscribe();      });    });    expect(out!()).toBe("Hi");    set!("John");    expect(out!()).toBe("John");  });});