net: simplify Socket.prototype._final

Remove conditions that should be irrelevant since we started
using `_final`, as well as an extra `defaultTriggerAsyncIdScope()`
call which is unnecessary because there is an equivalent
scope already present on the native side.
PR-URL: #24075
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: addaleax

lib/net.js

@@ -335,14 +335,6 @@ Socket.prototype._unrefTimer = function _unrefTimer() {
 };
 
 
-functionshutdownSocket(self,callback){
-varreq=newShutdownWrap();
-req.oncomplete=afterShutdown;
-req.handle=self._handle;
-req.callback=callback;
-returnself._handle.shutdown(req);
-}
-
 // the user has called .end(), and all the bytes have been
 // sent out to the other side.
 Socket.prototype._final=function(cb){
@@ -352,23 +344,16 @@ Socket.prototype._final = function(cb) {
 returnthis.once('connect',()=>this._final(cb));
 }
 
-if(!this.readable||this._readableState.ended){
-debug('_final: ended, destroy',this._readableState);
-cb();
-returnthis.destroy();
-}
+if(!this._handle)
+returncb();
 
 debug('_final: not ended, call shutdown()');
 
-// otherwise, just shutdown, or destroy() if not possible
-if(!this._handle||!this._handle.shutdown){
-cb();
-returnthis.destroy();
-}
-
-varerr=defaultTriggerAsyncIdScope(
-this[async_id_symbol],shutdownSocket,this,cb
-);
+varreq=newShutdownWrap();
+req.oncomplete=afterShutdown;
+req.handle=this._handle;
+req.callback=cb;
+varerr=this._handle.shutdown(req);
 
 if(err)
 returnthis.destroy(errnoException(err,'shutdown'));
@@ -387,7 +372,7 @@ function afterShutdown(status, handle) {
 if(self.destroyed)
 return;
 
-if(self._readableState.ended){
+if(!self.readable||self._readableState.ended){
 debug('readableState ended, destroying');
 self.destroy();
 }