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import assert from "assert";import { CachedKeyDecoder, KeyDecoder } from "../src/CachedKeyDecoder";import { utf8EncodeJs, utf8Count } from "../src/utils/utf8";
function tryDecode(keyDecoder: KeyDecoder, str: string): string {  const byteLength = utf8Count(str);  const bytes = new Uint8Array(byteLength);  utf8EncodeJs(str, bytes, 0);  if (!keyDecoder.canBeCached(byteLength)) {    throw new Error("Unexpected precondition");  }  return keyDecoder.decode(bytes, 0, byteLength);}
describe("CachedKeyDecoder", () => {  context("basic behavior", () => {    it("decodes a string", () => {      const decoder = new CachedKeyDecoder();
      assert.deepStrictEqual(tryDecode(decoder, "foo"), "foo");      assert.deepStrictEqual(tryDecode(decoder, "foo"), "foo");      assert.deepStrictEqual(tryDecode(decoder, "foo"), "foo");
      // console.dir(decoder, { depth: 100 });    });
    it("decodes strings", () => {      const decoder = new CachedKeyDecoder();
      assert.deepStrictEqual(tryDecode(decoder, "foo"), "foo");      assert.deepStrictEqual(tryDecode(decoder, "bar"), "bar");      assert.deepStrictEqual(tryDecode(decoder, "foo"), "foo");
      // console.dir(decoder, { depth: 100 });    });
    it("decodes strings with purging records", () => {      const decoder = new CachedKeyDecoder(16, 4);
      for (let i = 0; i < 100; i++) {        assert.deepStrictEqual(tryDecode(decoder, "foo1"), "foo1");        assert.deepStrictEqual(tryDecode(decoder, "foo2"), "foo2");        assert.deepStrictEqual(tryDecode(decoder, "foo3"), "foo3");        assert.deepStrictEqual(tryDecode(decoder, "foo4"), "foo4");        assert.deepStrictEqual(tryDecode(decoder, "foo5"), "foo5");      }
      // console.dir(decoder, { depth: 100 });    });  });
  context("edge cases", () => {    // len=0 is not supported because it is just an empty string    it("decodes str with len=1", () => {      const decoder = new CachedKeyDecoder();
      assert.deepStrictEqual(tryDecode(decoder, "f"), "f");      assert.deepStrictEqual(tryDecode(decoder, "a"), "a");      assert.deepStrictEqual(tryDecode(decoder, "f"), "f");      assert.deepStrictEqual(tryDecode(decoder, "a"), "a");
      // console.dir(decoder, { depth: 100 });    });
    it("decodes str with len=maxKeyLength", () => {      const decoder = new CachedKeyDecoder(1);
      assert.deepStrictEqual(tryDecode(decoder, "f"), "f");      assert.deepStrictEqual(tryDecode(decoder, "a"), "a");      assert.deepStrictEqual(tryDecode(decoder, "f"), "f");      assert.deepStrictEqual(tryDecode(decoder, "a"), "a");
      //console.dir(decoder, { depth: 100 });    });  });});