devtools/client/debugger/src/actions/utils/middleware/timing.js


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/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at <http://mozilla.org/MPL/2.0/>. */

/**
 * Redux middleware that sets performance markers for all actions such that they
 * will appear in performance tooling under the User Timing API
 */

const mark = window.performance?.mark
  ? window.performance.mark.bind(window.performance)
  : () => {};

const measure = window.performance?.measure
  ? window.performance.measure.bind(window.performance)
  : () => {};

export function timing() {
  return next => action => {
    mark(`${action.type}_start`);
    const result = next(action);
    mark(`${action.type}_end`);
    measure(`${action.type}`, `${action.type}_start`, `${action.type}_end`);
    return result;
  };
}