import { enableMapSet, produce } from "./mod.ts";
import {
  assertEquals,
  assertNotStrictEquals,
  assertStrictEquals,
} from "https://deno.land/std@0.173.0/testing/asserts.ts";

enableMapSet();

Deno.test("Immer", async (t) => {
  const before = new Map([["key1", { title: "test" }]]);
  const after = new Map([["key1", { title: "test" }]]);

  // 構造は同じだが別の参照
  assertEquals(before, after);
  assertNotStrictEquals(before, after);
  
  await t.step("objectを入れ替えるときはreturnする", () => {
    const next = produce<typeof before>(before, () => after);
  
    assertNotStrictEquals(before, next);
    assertStrictEquals(after, next);
  });
  await t.step("何か破壊的操作があると、値が同じでも別のobjectになる", () => {
    {
      const next = produce<typeof before>(before, (draft) => {
        draft.clear();
        for (const [key, value] of after) {
          draft.set(key, value);
        }
      });
    
      assertNotStrictEquals(before, next);
    }
    {
      const next = produce<typeof before>(before, (draft) => {
        const value = draft.get("key1");
        if (!value) return;
        draft.clear();
        draft.set("key1", value);
      });
    
      assertNotStrictEquals(before, next);
    }
  });
  await t.step("変更がなければ同じobjectを返す", () => {
    const next = produce<typeof before>(before, (draft) => {});
    assertStrictEquals(before, next);
  });
});