test("basic functionality", () => { expect(String.raw).toHaveLength(1); let str = String.raw`foo\nbar`; expect(str).toHaveLength(8); expect(str).toBe("foo\\nbar"); str = String.raw`foo ${1 + 9}\nbar${"hf!"}`; expect(str).toBe("foo 10\\nbarhf!"); str = String.raw`${10}${20}${30}`; expect(str).toBe("102030"); str = String.raw({ raw: ["foo ", "\\nbar"] }, 10, "hf!"); expect(str).toBe("foo 10\\nbar"); str = String.raw({ raw: ["foo ", "\\nbar"] }); expect(str).toBe("foo \\nbar"); str = String.raw({ raw: [] }, 10, "hf!"); expect(str).toBe(""); str = String.raw({ raw: 1 }); expect(str).toBe(""); }); test("passing object with no 'raw' property", () => { expect(() => { String.raw({}); }).toThrowWithMessage(TypeError, "ToObject on null or undefined"); });