export async function expectThrow(promise: Promise<any>, expectedRevertMessage?: string) {
  try {
    await promise;
  } catch (error) {
    if (expectedRevertMessage) {
      const message = error.message.search(expectedRevertMessage) >= 0;
      assert(message, "Expected throw with message " + expectedRevertMessage + ", got '" + error + "' instead");
    } else {
      const revert = error.message.search("revert") >= 0;
      const invalidOpcode = error.message.search("invalid opcode") >= 0;
      assert(revert || invalidOpcode, "Expected throw, got '" + error + "' instead");
    }
    return;
  }
  assert.fail("Expected throw not received");
}