Function isLineDiffableArg

packages/expect/src/spyMatchers.ts:272–311

(expected: unknown, received: unknown)

// Almost redundant with function in jest-matcher-utils,
// except no line diff for any strings.
const isLineDiffableArg = (expected: unknown, received: unknown): boolean => {
  const expectedType = getType(expected);
  const receivedType = getType(received);

  if (expectedType !== receivedType) {
    return false;
  }

  if (isPrimitive(expected)) {
    return false;
  }

  if (
    expectedType === 'date' ||
    expectedType === 'function' ||
    expectedType === 'regexp'
  ) {
    return false;
  }

  if (expected instanceof Error && received instanceof Error) {
    return false;
  }

  if (
    expectedType === 'object' &&
    typeof (expected as any).asymmetricMatch === 'function'
  ) {
    return false;
  }

  if (
    receivedType === 'object' &&
    typeof (received as any).asymmetricMatch === 'function'
  ) {
    return false;
  }

  return true;
};

const printResult = (result: any, expected: unknown) =>
  result.type === 'throw'