Function expect

packages/expect/src/index.ts:105–157

(actual: any, ...rest: Array<any>)

};

export const expect: Expect = (actual: any, ...rest: Array<any>) => {
  if (rest.length > 0) {
    throw new Error(class="st">'Expect takes at most one argument.');
  }

  const allMatchers = getMatchers();
  const expectation: any = {
    not: {},
    rejects: {not: {}},
    resolves: {not: {}},
  };

  const err = new JestAssertionError();

  for (const name of Object.keys(allMatchers)) {
    const matcher = allMatchers[name];
    const promiseMatcher = getPromiseMatcher(name, matcher) || matcher;
    expectation[name] = makeThrowingMatcher(matcher, false, class="st">'', actual);
    expectation.not[name] = makeThrowingMatcher(matcher, true, class="st">'', actual);

    expectation.resolves[name] = makeResolveMatcher(
      name,
      promiseMatcher,
      false,
      actual,
      err,
    );
    expectation.resolves.not[name] = makeResolveMatcher(
      name,
      promiseMatcher,
      true,
      actual,
      err,
    );

    expectation.rejects[name] = makeRejectMatcher(
      name,
      promiseMatcher,
      false,
      actual,
      err,
    );
    expectation.rejects.not[name] = makeRejectMatcher(
      name,
      promiseMatcher,
      true,
      actual,
      err,
    );
  }

  return expectation;
};

const getMessage = (message?: () => string) =>
  (message && message()) ||