text: import KeywordIndex from "../biz-logic/KeywordIndex";
  
  let keywordIndex;
  
  beforeEach(() => {
    keywordIndex = new KeywordIndex();
  });
  
  test("if index is empty and passed no keywords, idsFor returns empty collection", () => {
    const matchingIds = keywordIndex.idsFor([]);
  
    expect(matchingIds).toStrictEqual([]);
  });
  
  test("if index is empty and passed 1 keyword, idsFor returns empty collection", () => {
    const matchingIds = keywordIndex.idsFor(["foo"]);
  
    expect(matchingIds).toStrictEqual([]);
  });
  
  test("if index is empty and passed 2 different keywords, idsFor returns empty collection", () => {
    const matchingIds = keywordIndex.idsFor(["foo", "bar"]);
  
    expect(matchingIds).toStrictEqual([]);
  });
  
  test("if index is empty and passed a bunch of keywords, idsFor returns empty collection", () => {
    const matchingIds = keywordIndex.idsFor([
      "foo",
      "bar",
      "baz",
      "qux",
      "foo",
      "w",
      "LIL'ABNER"
    ]);
  
    expect(matchingIds).toStrictEqual([]);
  });
  