test: increase coverage for events

1. test EventEmitter.setMaxListeners with invalid listener count https://coverage.nodejs.org/coverage-0b6d3070a176d437/lib/events.js.html#L171 2. test EventEmitter.setMaxListeners with invalid emitter https://coverage.nodejs.org/coverage-0b6d3070a176d437/lib/events.js.html#L186 3. test getEventListeners with invalid emiiter Refs: https://coverage.nodejs.org/coverage-0b6d3070a176d437/lib/events.js.html#L706 4. test events.once with options: null Refs: https://coverage.nodejs.org/coverage-0b6d3070a176d437/lib/events.js.html#L712 5. add test case for inspect new Event() Refs: https://coverage.nodejs.org/coverage-0b6d3070a176d437/lib/internal/event_target.js.html#L111 6. add test case for insepct new EventTarget() Refs: https://coverage.nodejs.org/coverage-0b6d3070a176d437/lib/internal/event_target.js.html#L446 7. add test case for Event and EventTarget constructor name PR-URL: #36668 Reviewed-By: Benjamin Gruenbaum <[email protected]> Reviewed-By: James M Snell <[email protected]> Reviewed-By: Rich Trott <[email protected]>

Author: Lxxyx

test/parallel/test-event-emitter-max-listeners.js

@@ -56,3 +56,17 @@ for (const obj of throwsObjs){
 }
 
 e.emit('maxListeners');
+
+{
+const{ EventEmitter, defaultMaxListeners }=events;
+for(constobjofthrowsObjs){
+assert.throws(()=>EventEmitter.setMaxListeners(obj),{
+code: 'ERR_OUT_OF_RANGE',
+});
+}
+
+assert.throws(
+()=>EventEmitter.setMaxListeners(defaultMaxListeners,'INVALID_EMITTER'),
+{code: 'ERR_INVALID_ARG_TYPE'}
+);
+}

test/parallel/test-events-once.js

@@ -23,6 +23,18 @@ async function onceAnEvent(){
 strictEqual(ee.listenerCount('myevent'),0);
 }
 
+asyncfunctiononceAnEventWithNullOptions(){
+constee=newEventEmitter();
+
+process.nextTick(()=>{
+ee.emit('myevent',42);
+});
+
+const[value]=awaitonce(ee,'myevent',null);
+strictEqual(value,42);
+}
+
+
 asyncfunctiononceAnEventWithTwoArgs(){
 constee=newEventEmitter();
 
@@ -195,6 +207,7 @@ async function eventTargetAbortSignalAfterEvent(){
 
 Promise.all([
 onceAnEvent(),
+onceAnEventWithNullOptions(),
 onceAnEventWithTwoArgs(),
 catchesErrors(),
 stopListeningAfterCatchingError(),

test/parallel/test-events-static-geteventlisteners.js

@@ -4,6 +4,7 @@ const common = require('../common');
 
 const{
  deepStrictEqual,
+ throws
 }=require('assert');
 
 const{ getEventListeners, EventEmitter }=require('events');
@@ -34,3 +35,9 @@ const{getEventListeners, EventEmitter } = require('events');
 deepStrictEqual(getEventListeners(target,'bar'),[]);
 deepStrictEqual(getEventListeners(target,'baz'),[fn1]);
 }
+
+{
+throws(()=>{
+getEventListeners('INVALID_EMITTER');
+},/ERR_INVALID_ARG_TYPE/);
+}

test/parallel/test-eventtarget.js

@@ -13,7 +13,7 @@ const{
 
 const{ once }=require('events');
 
-const{ promisify }=require('util');
+const{ promisify, inspect}=require('util');
 constdelay=promisify(setTimeout);
 
 // The globals are defined.
@@ -541,3 +541,32 @@ let asyncTest = Promise.resolve();
 et.addEventListener('foo',listener);
 et.dispatchEvent(newEvent('foo'));
 }
+
+{
+constev=newEvent('test');
+constevConstructorName=inspect(ev,{
+depth: -1
+});
+strictEqual(evConstructorName,'Event');
+
+constinspectResult=inspect(ev,{
+depth: 1
+});
+ok(inspectResult.includes('Event'));
+}
+
+{
+constet=newEventTarget();
+constinspectResult=inspect(et,{
+depth: 1
+});
+ok(inspectResult.includes('EventTarget'));
+}
+
+{
+constev=newEvent('test');
+strictEqual(ev.constructor.name,'Event');
+
+constet=newEventTarget();
+strictEqual(et.constructor.name,'EventTarget');
+}