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import select, { none } from "./select.ts";import { assertEquals } from "testing/asserts.ts";
Deno.test("select path", () => {  const ref = {};
  const obj = {    a: {      b: "c",    },    d: "e",    f: undefined,    g: [{ foo: "bar" }, { foo: "baz" }],    map: new Map([["a", "b"], ["c", "d"]]),    map2: new Map<unknown, string>(),    boolMap: new Map<boolean, number>(),    nestMap: new Map([["a", [      0,      new Map([[ref, { foo: "bar" }]]),    ]]]),  } as const;
  assertEquals(select(obj, "a"), { b: "c" });  assertEquals(select(obj, "a", "b"), "c");  assertEquals(select(obj, "f"), undefined);  assertEquals(select(obj, "z"), none);  assertEquals(select(obj, "a", "z"), none);  assertEquals(select(obj, "d", "e"), none);  assertEquals(select(obj, "g", 0, "foo"), "bar");  assertEquals(select(obj, "g", 1, "foo"), "baz");  assertEquals(select(obj, "map", "a"), "b");  assertEquals(select(obj, "map", "c"), "d");  assertEquals(select(obj, "map", "e"), none);  assertEquals(select(obj, "nestMap", "a", 1, ref, "foo"), "bar");
  {    const _a_b: "c" = select(obj, "a", "b");    const _a_z: typeof none = select(obj, "a", "z");  }  {    // @ts-expect-error    const _a_b2: "c" = select(obj as unknown, "a", "b");    const _a_b1: unknown = select(obj as unknown, "a", "b");
    // @ts-expect-error    const _a_z1: typeof none = select(obj as unknown, "a", "z");    const _a_z2: unknown = select(obj as unknown, "a", "z");  }  {    // @ts-expect-error    const _bm_f1: number = select(obj, "boolMap", false);    // @ts-expect-error    const _bm_f2: string | typeof none = select(obj, "boolMap", false);    const _bm_f3: number | typeof none = select(obj, "boolMap", false);
    const _m_k1: typeof none = select(obj, "map", 2);    const _m_k2: string | typeof none = select(obj, "map", "foo");
    const _m2_k1: string | typeof none = select(obj, "map2", "a");    const _m2_k2: string | typeof none = select(obj, "map2", 2);  }});