35 lines
1.0 KiB
TypeScript
35 lines
1.0 KiB
TypeScript
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/*
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Copyright 2026 Element Creations Ltd.
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SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
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Please see LICENSE in the repository root for full details.
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*/
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import { renderHook } from "@testing-library/react";
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import { describe, expect, test } from "vitest";
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import { useValueBehavior } from "./useValueBehavior";
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describe("useValueBehavior", () => {
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test("holds the value from the first render", () => {
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const { result } = renderHook(({ value }) => useValueBehavior(value), {
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initialProps: { value: "a" },
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});
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expect(result.current.value).toBe("a");
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});
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test("keeps one identity and takes each new value", () => {
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const { result, rerender } = renderHook(
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({ value }) => useValueBehavior(value),
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{ initialProps: { value: "a" } },
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);
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const value$ = result.current;
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const seen: string[] = [];
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value$.subscribe((value) => seen.push(value));
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rerender({ value: "b" });
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expect(result.current).toBe(value$);
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expect(seen).toEqual(["a", "b"]);
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});
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});
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