Function ensureMockOrSpy

packages/expect/src/spyMatchers.ts:1265–1280

(
  received: any,
  matcherName: string,
  expectedArgument: string,
  options: MatcherHintOptions,
)

  typeof received.calls.count === 'function';

const ensureMockOrSpy = (
  received: any,
  matcherName: string,
  expectedArgument: string,
  options: MatcherHintOptions,
) => {
  if (!isMock(received) && !isSpy(received)) {
    throw new Error(
      matcherErrorMessage(
        matcherHint(matcherName, undefined, expectedArgument, options),
        `${RECEIVED_COLOR('received')} value must be a mock or spy function`,
        printWithType('Received', received, printReceived),
      ),
    );
  }
};

const ensureMock = (
  received: any,