Function toggleExperiment

src/experiments/index.js:77–106

(
  win,
  experimentId,
  opt_on,
  opt_transientExperiment
)

 * @return {boolean} New state for experimentId.
 */
export function toggleExperiment(
  win,
  experimentId,
  opt_on,
  opt_transientExperiment
) {
  const currentlyOn = isExperimentOn(win, /*OK*/ experimentId);
  const on = opt_on ?? !currentlyOn;
  if (on != currentlyOn) {
    const toggles = experimentToggles(win);
    toggles[experimentId] = on;

    if (!opt_transientExperiment) {
      const storedToggles = getExperimentToggles(win);
      storedToggles[experimentId] = on;
      saveExperimentToggles(win, storedToggles);
      // Avoid affecting tests that spy/stub warn().
      if (!getMode().test) {
        user().warn(
          TAG,
          '"%s" experiment %s for the domain "%s". See: https://amp.dev/documentation/guides-and-tutorials/learn/experimental',
          experimentId,
          on ? 'enabled' : 'disabled',
          win.location.hostname
        );
      }
    }
  }
  return on;
}

/**
 * Calculate whether the experiment is on or off based off of its default value,