repl: avoid using forEach

PR-URL: #11582
Reviewed-By: Matteo Collina <[email protected]>
Reviewed-By: Colin Ihrig <[email protected]>

Author: jasnell

lib/repl.js

@@ -47,7 +47,10 @@ const GLOBAL_OBJECT_PROPERTIES = [
   'ReferenceError', 'SyntaxError', 'TypeError', 'URIError', 'Math', 'JSON'
 ];
 const GLOBAL_OBJECT_PROPERTY_MAP = {};
-GLOBAL_OBJECT_PROPERTIES.forEach((p) => GLOBAL_OBJECT_PROPERTY_MAP[p] = p);
+for (var n = 0; n < GLOBAL_OBJECT_PROPERTIES.length; n++) {
+  GLOBAL_OBJECT_PROPERTY_MAP[GLOBAL_OBJECT_PROPERTIES[n]] =
+    GLOBAL_OBJECT_PROPERTIES[n];
+}
 
 try {
   // hack for require.resolve("./relative") to work properly.
@@ -692,13 +695,17 @@ REPLServer.prototype.createContext = function() {
       enumerable: true,
       get: () => _console
     });
-    Object.getOwnPropertyNames(global).filter((name) => {
-      if (name === 'console' || name === 'global') return false;
-      return GLOBAL_OBJECT_PROPERTY_MAP[name] === undefined;
-    }).forEach((name) => {
-      Object.defineProperty(context, name,
-                            Object.getOwnPropertyDescriptor(global, name));
-    });
+
+    var names = Object.getOwnPropertyNames(global);
+    for (var n = 0; n < names.length; n++) {
+      var name = names[n];
+      if (name === 'console' || name === 'global')
+        continue;
+      if (GLOBAL_OBJECT_PROPERTY_MAP[name] === undefined) {
+        Object.defineProperty(context, name,
+                              Object.getOwnPropertyDescriptor(global, name));
+      }
+    }
   }
 
   const module = new Module('<repl>');
@@ -769,10 +776,8 @@ function ArrayStream() {
   Stream.call(this);
 
   this.run = function(data) {
-    var self = this;
-    data.forEach(function(line) {
-      self.emit('data', line + '\n');
-    });
+    for (var n = 0; n < data.length; n++)
+      this.emit('data', `${data[n]}\n`);
   };
 }
 util.inherits(ArrayStream, Stream);
@@ -816,11 +821,11 @@ function complete(line, callback) {
     var tmp = this.lines.slice();
     // Kill off all function declarations to push all local variables into
     // global scope
-    this.lines.level.forEach(function(kill) {
-      if (kill.isFunction) {
+    for (var n = 0; n < this.lines.level.length; n++) {
+      var kill = this.lines.level[n];
+      if (kill.isFunction)
         tmp[kill.line] = '';
-      }
-    });
+    }
     var flat = new ArrayStream();         // make a new "input" stream
     var magic = new REPLServer('', flat); // make a nested REPL
     replMap.set(magic, replMap.get(this));
@@ -954,9 +959,8 @@ function complete(line, callback) {
               addStandardGlobals(completionGroups, filter);
             } else if (Array.isArray(globals[0])) {
               // Add grouped globals
-              globals.forEach(function(group) {
-                completionGroups.push(group);
-              });
+              for (var n = 0; n < globals.length; n++)
+                completionGroups.push(globals[n]);
             } else {
               completionGroups.push(globals);
               addStandardGlobals(completionGroups, filter);
@@ -1264,12 +1268,13 @@ function defineDefaultCommands(repl) {
         (max, name) => Math.max(max, name.length),
         0
       );
-      names.forEach((name) => {
-        const cmd = this.commands[name];
-        const spaces = ' '.repeat(longestNameLength - name.length + 3);
-        const line = '.' + name + (cmd.help ? spaces + cmd.help : '') + '\n';
+      for (var n = 0; n < names.length; n++) {
+        var name = names[n];
+        var cmd = this.commands[name];
+        var spaces = ' '.repeat(longestNameLength - name.length + 3);
+        var line = `.${name}${cmd.help ? spaces + cmd.help : ''}\n`;
         this.outputStream.write(line);
-      });
+      }
       this.displayPrompt();
     }
   });
@@ -1293,15 +1298,13 @@ function defineDefaultCommands(repl) {
       try {
         var stats = fs.statSync(file);
         if (stats && stats.isFile()) {
-          var self = this;
           var data = fs.readFileSync(file, 'utf8');
           var lines = data.split('\n');
           this.displayPrompt();
-          lines.forEach(function(line) {
-            if (line) {
-              self.write(line + '\n');
-            }
-          });
+          for (var n = 0; n < lines.length; n++) {
+            if (lines[n])
+              this.write(`${lines[n]}\n`);
+          }
         } else {
           this.outputStream.write('Failed to load:' + file +
                                   ' is not a valid file\n');