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import { LRUMap } from "./lru_map.ts";import {  assertEquals,  assertInstanceOf,  assertNotEquals,  assertThrows,  describe,  it,} from "./dev_deps.ts";
const OVER_MAX_SAFE_ITEMS = Math.pow(2, 25); // 2^24 is max
function assertEqualsLRU(  left: LRUMap<unknown, unknown>,  right: Map<unknown, unknown>,) {  assertEquals(new Map(left.entries()), right);  assertEquals([...left.entries()], [...right.entries()]);}
describe("LRUMap", () => {  it("should equal Map", () => {    assertInstanceOf(new LRUMap(0), Map);  });
  it("should not equal prototype Map", () => {    assertNotEquals(LRUMap.prototype, Map.prototype);  });
  it("should rollup entries limited by max size", () => {    const key = {};    const table: [      actual: Map<unknown, unknown>,      result: Map<unknown, unknown>,    ][] = [      [new LRUMap(0, []), new Map()],      [new LRUMap(1, [[0, 1]]), new Map([[0, 1]])],      [new LRUMap(0, [[0, 1]]), new Map()],      [new LRUMap(-1, [[0, 1]]), new Map()],      [new LRUMap(NaN, [[0, 1]]), new Map()],      [        new LRUMap(2, [[0, 1], [1, 2], [2, 3], [3, 4]]),        new Map([[2, 3], [3, 4]]),      ],      [        new LRUMap(2, [[0, 1], [1, 2], [2, 3], [3, 4]]),        new Map([[2, 3], [3, 4]]),      ],      [new LRUMap(1, [[{}, {}]]), new Map([[{}, {}]])],      [new LRUMap(2, [[{}, {}], [{}, {}]]), new Map([[{}, {}], [{}, {}]])],      [new LRUMap(2, [[key, {}], [key, {}]]), new Map([[key, {}]])],    ];
    table.forEach(([actual, expected]) => {      assertEqualsLRU(actual, expected);    });  });
  it("should rollup entries when set value", () => {    const table: [      actual: Map<unknown, unknown>,      result: Map<unknown, unknown>,    ][] = [      [new LRUMap(0).set("", ""), new Map()],      [new LRUMap(0).set("", "").set("a", "b"), new Map()],      [new LRUMap(-1).set("", ""), new Map()],      [new LRUMap(1).set("", ""), new Map([["", ""]])],      [new LRUMap(1).set("", "a").set("", "b"), new Map([["", "b"]])],      [new LRUMap(1).set("", "a").set("a", "b"), new Map([["a", "b"]])],      [        new LRUMap(1).set("", "a").set("a", "b").set("b", "c"),        new Map([["b", "c"]]),      ],      [        new LRUMap(1).set("", "a").set("", "b").set("", "c"),        new Map([["", "c"]]),      ],      [        new LRUMap(2).set("", ""),        new Map([["", ""]]),      ],      [        new LRUMap(2).set("", "").set("", ""),        new Map([["", ""]]),      ],      [        new LRUMap(2).set("", "").set("", "a"),        new Map([["", "a"]]),      ],      [        new LRUMap(2).set("", "").set("", "a").set("a", "b"),        new Map([["", "a"], ["a", "b"]]),      ],      [        new LRUMap(2).set("", "").set("a", "a").set("b", "b").set("c", "c"),        new Map([["b", "b"], ["c", "c"]]),      ],      [        new LRUMap(2).set("", "").set("a", "a").set("b", "b").set("a", "new"),        new Map([["b", "b"], ["a", "new"]]),      ],    ];
    table.forEach(([actual, expected]) => {      assertEqualsLRU(actual, expected);    });  });
  it("should rollup entries when get the key", () => {    const lrn = new LRUMap(5, [["", ""], ["a", "a"]]);    lrn.get("");
    assertEqualsLRU(lrn, new Map([["a", "a"], ["", ""]]));  });
  it("should not rollup entries when the key does not exists", () => {    const lrn = new LRUMap(5, [["", ""], ["a", "a"]]);    lrn.get("b");
    assertEqualsLRU(lrn, new Map([["", ""], ["a", "a"]]));  });
  it("should equal map complex pattern", () => {    const lru = new LRUMap(4, [["", ""], ["a", "a"], ["b", "b"]]);
    lru.set("", "new ");    lru.get("a");    lru.set("c", "c");    lru.get("");    lru.set("d", "d");
    assertEqualsLRU(      lru,      new Map([["a", "a"], ["c", "c"], ["", "new "], ["d", "d"]]),    );  });
  it("should throw error when map items exceed 2^24", () => {    const m = new Map();
    assertThrows(() => {      for (const a of range(OVER_MAX_SAFE_ITEMS)) {        m.set(a, a);      }    });  });
  it("should not throw error when the LRU has limit", () => {    const m = new LRUMap(1);    for (const a of range(OVER_MAX_SAFE_ITEMS)) {      m.set(a, a);    }    assertEquals(m.size, 1);  });
  it("should throw error when the LRU limit exceed map limit", () => {    const m = new LRUMap(OVER_MAX_SAFE_ITEMS);
    assertThrows(() => {      for (const a of range(OVER_MAX_SAFE_ITEMS)) {        m.set(a, a);      }    });  });
  it("should success the examples", () => {    const map = new LRUMap(2, [[0, "left"], [1, "right"]]);    assertEquals([...map.entries()], [[0, "left"], [1, "right"]]);
    map.get(0);    assertEquals([...map.entries()], [[1, "right"], [0, "left"]]);  });});
function* range(limit: number): Generator<number, void, unknown> {  let count = 0;  while (count < limit) {    yield count;    count++;  }}