function Expectation(options) {
      this.expector = new j$.Expector(options);

      const customMatchers = options.customMatchers || {};
      for (const matcherName in customMatchers) {
        this[matcherName] = wrapSyncCompare(matcherName, customMatchers[matcherName]);
      }
    }
Matchers that come with Jasmine out of the box.
@namespace matchers