material-components_material-web/testing/skip-animations.ts

/**
 * @license
 * Copyright 2022 Google LLC
 * SPDX-License-Identifier: Apache-2.0
 */

/** Overrides the browsers native animate to make them run in 1ms */
export function installSkipWebAnimations() {
  const nativeAnimate = Element.prototype.animate;
  function patchedAnimate(
      this: Element, ...args: Parameters<typeof nativeAnimate>) {
    const animation = nativeAnimate.apply(this, args);
    if (animation.effect) {
      animation.effect.updateTiming(
          {delay: 0, duration: 1, easing: 'step-start', iterations: 1});
    }

    return animation;
  }

  Object.defineProperty(Element.prototype, 'animate', {
    configurable: true,
    enumerable: true,
    writable: true,
    value: patchedAnimate
  });

  // return uninstall function.
  return () => {
    Object.defineProperty(Element.prototype, 'animate', {
      configurable: true,
      enumerable: true,
      writable: true,
      value: nativeAnimate
    });
  };
}