Function isAsymmetric

packages/expect/src/jest-utils.ts:43–50

(obj: any)

const functionToString = Function.prototype.toString

export function isAsymmetric(obj: any): obj is AsymmetricMatcher<any> {
  return (
    !!obj
    && typeof obj === 'object'
    && 'asymmetricMatch' in obj
    && isA('Function', obj.asymmetricMatch)
  )
}

export function hasAsymmetric(obj: any, seen: Set<any> = new Set()): boolean {
  if (seen.has(obj)) {