Allow for two streams in REPL

Towards windows compatibility.

lib/repl.js

@@ -52,10 +52,19 @@ function REPLServer(prompt, stream) {
   self.context = context;
   self.bufferedCommand = '';
 
-  self.stream = stream || process.openStdin();
+  if (stream) {
+    // We're given a duplex socket
+    self.outputStream = stream;
+    self.inputStream = stream;
+  } else {
+    self.outputStream = process.stdout;
+    self.inputStream = process.stdin;
+    process.stdin.resume();
+  }
+
   self.prompt = prompt || '> ';
 
-  var rli = self.rli = rl.createInterface(self.stream, function(text) {
+  var rli = self.rli = rl.createInterface(self.outputStream, function(text) {
     return self.complete(text);
   });
 
@@ -81,7 +90,7 @@ function REPLServer(prompt, stream) {
     }
   });
 
-  self.stream.addListener('data', function(chunk) {
+  self.inputStream.addListener('data', function(chunk) {
     rli.write(chunk);
   });
 
@@ -98,7 +107,7 @@ function REPLServer(prompt, stream) {
       if (self.parseREPLKeyword(keyword, rest) === true) {
         return;
       } else {
-        self.stream.write('Invalid REPL keyword\n');
+        self.outputStream.write('Invalid REPL keyword\n');
         skipCatchall = true;
       }
     }
@@ -132,7 +141,7 @@ function REPLServer(prompt, stream) {
 
           if (ret !== undefined) {
             context._ = ret;
-            self.stream.write(exports.writer(ret) + '\n');
+            self.outputStream.write(exports.writer(ret) + '\n');
           }
 
           self.bufferedCommand = '';
@@ -151,9 +160,9 @@ function REPLServer(prompt, stream) {
       } catch (e) {
         // On error: Print the error and clear the buffer
         if (e.stack) {
-          self.stream.write(e.stack + '\n');
+          self.outputStream.write(e.stack + '\n');
         } else {
-          self.stream.write(e.toString() + '\n');
+          self.outputStream.write(e.toString() + '\n');
         }
         self.bufferedCommand = '';
       }
@@ -163,7 +172,7 @@ function REPLServer(prompt, stream) {
   });
 
   rli.addListener('close', function() {
-    self.stream.destroy();
+    self.inputStream.destroy();
   });
 
   self.displayPrompt();
@@ -465,7 +474,7 @@ function defineDefaultCommands(repl) {
   repl.defineCommand('clear', {
     help: 'Break, and also clear the local context',
     action: function() {
-      this.stream.write('Clearing context...\n');
+      this.outputStream.write('Clearing context...\n');
       this.bufferedCommand = '';
       resetContext();
       this.displayPrompt();
@@ -485,7 +494,7 @@ function defineDefaultCommands(repl) {
       var self = this;
       Object.keys(this.commands).sort().forEach(function(name) {
         var cmd = self.commands[name];
-        self.stream.write(name + '\t' + (cmd.help || '') + '\n');
+        self.outputStream.write(name + '\t' + (cmd.help || '') + '\n');
       });
       this.displayPrompt();
     }