events: make sure console functions exist

If there's no global console cached, initialize it. Fixes: #4467 PR-URL: #4479 Reviewed-By: Roman Reiss <[email protected]> Reviewed-By: James M Snell <[email protected]>

Author: Dave

lib/events.js

@@ -18,7 +18,20 @@ EventEmitter.prototype._maxListeners = undefined;
 
 // By default EventEmitters will print a warning if more than 10 listeners are
 // added to it. This is a useful default which helps finding memory leaks.
-EventEmitter.defaultMaxListeners=10;
+vardefaultMaxListeners=10;
+
+Object.defineProperty(EventEmitter,'defaultMaxListeners',{
+enumerable: true,
+get: function(){
+returndefaultMaxListeners;
+},
+set: function(arg){
+// force global console to be compiled.
+// see https://github.com/nodejs/node/issues/4467
+console;
+defaultMaxListeners=arg;
+}
+});
 
 EventEmitter.init=function(){
 this.domain=null;

test/parallel/test-global-console-exists.js

@@ -0,0 +1,36 @@
+/* eslint-disable required-modules */
+// ordinarily test files must require('common') but that action causes
+// the global console to be compiled, defeating the purpose of this test
+
+'use strict';
+
+constassert=require('assert');
+constEventEmitter=require('events');
+constleak_warning=/EventEmittermemoryleakdetected\.2hellolisteners/;
+
+varwrite_calls=0;
+process.stderr.write=function(data){
+if(write_calls===0)
+assert.ok(data.match(leak_warning));
+elseif(write_calls===1)
+assert.ok(data.match(/Trace/));
+else
+assert.ok(false,'stderr.write should be called only twice');
+
+write_calls++;
+};
+
+constold_default=EventEmitter.defaultMaxListeners;
+EventEmitter.defaultMaxListeners=1;
+
+conste=newEventEmitter();
+e.on('hello',function(){});
+e.on('hello',function(){});
+
+// TODO: figure out how to validate console. Currently,
+// there is no obvious way of validating that console
+// exists here exactly when it should.
+
+assert.equal(write_calls,2);
+
+EventEmitter.defaultMaxListeners=old_default;