test: refactor event-emitter-remove-all-listeners

Use common.mustNotCall() to confirm that listener handles never run (as no events are emitted). PR-URL: #13165 Reviewed-By: Luigi Pinca <[email protected]> Reviewed-By: Colin Ihrig <[email protected]>

Author: Trott

test/parallel/test-event-emitter-remove-all-listeners.js

@@ -38,24 +38,25 @@ function expect(expected){
 
 {
 constee=newevents.EventEmitter();
-ee.on('foo',common.noop);
-ee.on('bar',common.noop);
-ee.on('baz',common.noop);
-ee.on('baz',common.noop);
+constnoop=common.mustNotCall();
+ee.on('foo',noop);
+ee.on('bar',noop);
+ee.on('baz',noop);
+ee.on('baz',noop);
 constfooListeners=ee.listeners('foo');
 constbarListeners=ee.listeners('bar');
 constbazListeners=ee.listeners('baz');
 ee.on('removeListener',expect(['bar','baz','baz']));
 ee.removeAllListeners('bar');
 ee.removeAllListeners('baz');
-assert.deepStrictEqual(ee.listeners('foo'),[common.noop]);
+assert.deepStrictEqual(ee.listeners('foo'),[noop]);
 assert.deepStrictEqual(ee.listeners('bar'),[]);
 assert.deepStrictEqual(ee.listeners('baz'),[]);
 // After calling removeAllListeners(),
 // the old listeners array should stay unchanged.
-assert.deepStrictEqual(fooListeners,[common.noop]);
-assert.deepStrictEqual(barListeners,[common.noop]);
-assert.deepStrictEqual(bazListeners,[common.noop,common.noop]);
+assert.deepStrictEqual(fooListeners,[noop]);
+assert.deepStrictEqual(barListeners,[noop]);
+assert.deepStrictEqual(bazListeners,[noop,noop]);
 // After calling removeAllListeners(),
 // new listeners arrays is different from the old.
 assert.notStrictEqual(ee.listeners('bar'),barListeners);
@@ -64,8 +65,8 @@ function expect(expected){
 
 {
 constee=newevents.EventEmitter();
-ee.on('foo',common.noop);
-ee.on('bar',common.noop);
+ee.on('foo',common.mustNotCall());
+ee.on('bar',common.mustNotCall());
 // Expect LIFO order
 ee.on('removeListener',expect(['foo','bar','removeListener']));
 ee.on('removeListener',expect(['foo','bar']));
@@ -76,7 +77,7 @@ function expect(expected){
 
 {
 constee=newevents.EventEmitter();
-ee.on('removeListener',common.noop);
+ee.on('removeListener',common.mustNotCall());
 // Check for regression where removeAllListeners() throws when
 // there exists a 'removeListener' listener, but there exists
 // no listeners for the provided event type.
@@ -89,9 +90,9 @@ function expect(expected){
 ee.on('removeListener',function(name,noop){
 assert.strictEqual(expectLength--,this.listeners('baz').length);
 });
-ee.on('baz',common.noop);
-ee.on('baz',common.noop);
-ee.on('baz',common.noop);
+ee.on('baz',common.mustNotCall());
+ee.on('baz',common.mustNotCall());
+ee.on('baz',common.mustNotCall());
 assert.strictEqual(ee.listeners('baz').length,expectLength+1);
 ee.removeAllListeners('baz');
 assert.strictEqual(ee.listeners('baz').length,0);