Class JobQueue

include/JobQueue.hh:24–150

* @brief Implement the ECMAScript Job Queue: * https://www.ecma-international.org/ecma-262/9.0/index.html#sec-jobs-and-job-queues * @see https://hg.mozilla.org/releases/mozilla-esr102/file/5741ffa/js/public/Promise.h#l22 */

 * @see https://hg.mozilla.org/releases/mozilla-esr102/file/5741ffa/js/public/Promise.h#l22
 */
class JobQueue : public JS::JobQueue {

public:
explicit JobQueue(JSContext *cx);
~JobQueue() = default;

/**
 * @brief Initialize PythonMonkey's event-loop job queue
 * @param cx - javascript context pointer
 * @return success
 */
bool init(JSContext *cx);

/**
 * @brief Ask the embedding for the host defined data.
 *
 * SpiderMonkey doesn't itself have a notion of host defined data as defined
 * by the HTML spec, so we need the embedding to provide this. See
 * dom/script/ScriptSettings.h for details.
 *
 * If the embedding has the host defined data, this method should return the
 * host defined data via the `data` out parameter and return `true`.
 * The object in the `data` out parameter can belong to any compartment.
 * If the embedding doesn't need the host defined data, this method should
 * set the `data` out parameter to `nullptr` and return `true`.
 * If any error happens while generating the host defined data, this method
 * should set a pending exception to `cx` and return `false`.
 */
bool getHostDefinedData(JSContext *cx, JS::MutableHandle<JSObject *> data) const override;

/**
 * @brief Enqueue a reaction job `job` for `promise`, which was allocated at
 * `allocationSite`. Provide `incumbentGlobal` as the incumbent global for
 * the reaction job's execution.
 *
 * `promise` can be null if the promise is optimized out.
 * `promise` is guaranteed not to be optimized out if the promise has
 * non-default user-interaction flag.
 */
bool enqueuePromiseJob(JSContext *cx, JS::HandleObject promise,
  JS::HandleObject job, JS::HandleObject allocationSite,
  JS::HandleObject incumbentGlobal) override;

/**
 * @brief Run all jobs in the queue. Running one job may enqueue others; continue to
 * run jobs until the queue is empty.
 *
 * Calling this method at the wrong time can break the web. The HTML spec
 * indicates exactly when the job queue should be drained (in HTML jargon,
 * when it should "perform a microtask checkpoint"), and doing so at other
 * times can incompatibly change the semantics of programs that use promises
 * or other microtask-based features.
 *
 * This method is called only via AutoDebuggerJobQueueInterruption, used by
 * the Debugger API implementation to ensure that the debuggee's job queue is
 * protected from the debugger's own activity. See the comments on
 * AutoDebuggerJobQueueInterruption.
 */