Function installYieldIt

testing/yield.js:7–11

(realIt)

 * Check test-yield.js for how-to.
 */
export function installYieldIt(realIt) {
  it = enableYield.bind(null, realIt); // eslint-disable-line no-native-reassign
  it./*OK*/ only = enableYield.bind(null, realIt.only);
  it.skip = realIt.skip;
}

function enableYield(fn, message, runnable) {
  if (