fs: do not crash when using a closed fs event watcher · nodejs/node@c09bfd8

// after the handle is closed, and to fire both UV_RENAME and UV_CHANGE

// if they are set by libuv at the same time.

if (status < 0) {

this._handle.close();

if (this._handle !== null) {

// We don't use this.close() here to avoid firing the close event.

this._handle.close();

this._handle = null; // make the handle garbage collectable

}

const error = errors.uvException({

errno: status,

syscall: 'watch',

// 1. Throw an Error if it's the first time .start() is called

// 2. Return silently if .start() has already been called

// on a valid filename and the wrap has been initialized

// 3. Return silently if the watcher has already been closed

// This method is a noop if the watcher has already been started.

FSWatcher.prototype.start = function(filename,

persistent,

recursive,

encoding) {

if (this._handle === null) { // closed

return;

}

assert(this._handle instanceof FSEvent, 'handle must be a FSEvent');

if (this._handle.initialized) {

if (this._handle.initialized) { // already started

return;

}

}

};

// This method is a noop if the watcher has not been started.

// This method is a noop if the watcher has not been started or

// has already been closed.

FSWatcher.prototype.close = function() {

if (this._handle === null) { // closed

return;

}

assert(this._handle instanceof FSEvent, 'handle must be a FSEvent');

if (!this._handle.initialized) {

if (!this._handle.initialized) { // not started

return;

}

this._handle.close();

this._handle = null; // make the handle garbage collectable

process.nextTick(emitCloseNT, this);

};