debugger: run last command on presssing enter

PR-URL: https://github.com/nodejs/node/pull/6090
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: bnoordhuis - Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Myles Borins <myles.borins@gmail.com>
Reviewed-By: Claudio Rodriguez <cjrodr@yahoo.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Fixes: https://github.com/nodejs/node/issues/2895

2 files changed, 26 insertions, 23 deletions

diff --git a/lib/_debugger.js b/lib/_debugger.js
index e7e24d32a1..7b3abec27d 100644
--- a/lib/_debugger.js
+++ b/lib/_debugger.js
@@ -674,6 +674,9 @@ var helpMessage = 'Commands: ' + commands.map(function(group) {
   return group.join(', ');
 }).join(',\n');
 
+// Previous command received. Initialize to empty command.
+var lastCommand = '\n';
+
 
 function SourceUnderline(sourceText, position, repl) {
   if (!sourceText) return '';
@@ -945,10 +948,10 @@ Interface.prototype.requireConnection = function() {
 Interface.prototype.controlEval = function(code, context, filename, callback) {
   try {
     // Repeat last command if empty line are going to be evaluated
-    if (this.repl.rli.history && this.repl.rli.history.length > 0) {
-      if (code === '\n') {
-        code = this.repl.rli.history[0] + '\n';
-      }
+    if (code === '\n') {
+      code = lastCommand;
+    } else {
+      lastCommand = code;
     }
 
     // exec process.title => exec("process.title");
diff --git a/lib/repl.js b/lib/repl.js
index 3a96eea136..82555497eb 100644
--- a/lib/repl.js
+++ b/lib/repl.js
@@ -224,6 +224,10 @@ function REPLServer(prompt,
   function defaultEval(code, context, file, cb) {
     var err, result, retry = false, input = code, wrappedErr;
     // first, create the Script object to check the syntax
+
+    if (code === '\n')
+      return cb(null);
+
     while (true) {
       try {
         if (!/^\s*$/.test(code) &&
@@ -421,28 +425,24 @@ function REPLServer(prompt,
       }
     }
 
-    if (cmd || self.bufferedCommand) {
-      var evalCmd = self.bufferedCommand + cmd;
-      if (/^\s*\{/.test(evalCmd) && /\}\s*$/.test(evalCmd)) {
-        // It's confusing for `{ a : 1 }` to be interpreted as a block
-        // statement rather than an object literal.  So, we first try
-        // to wrap it in parentheses, so that it will be interpreted as
-        // an expression.
-        evalCmd = '(' + evalCmd + ')\n';
-        self.wrappedCmd = true;
-      } else {
-        // otherwise we just append a \n so that it will be either
-        // terminated, or continued onto the next expression if it's an
-        // unexpected end of input.
-        evalCmd = evalCmd + '\n';
-      }
-
-      debug('eval %j', evalCmd);
-      self.eval(evalCmd, self.context, 'repl', finish);
+    var evalCmd = self.bufferedCommand + cmd;
+    if (/^\s*\{/.test(evalCmd) && /\}\s*$/.test(evalCmd)) {
+      // It's confusing for `{ a : 1 }` to be interpreted as a block
+      // statement rather than an object literal.  So, we first try
+      // to wrap it in parentheses, so that it will be interpreted as
+      // an expression.
+      evalCmd = '(' + evalCmd + ')\n';
+      self.wrappedCmd = true;
     } else {
-      finish(null);
+      // otherwise we just append a \n so that it will be either
+      // terminated, or continued onto the next expression if it's an
+      // unexpected end of input.
+      evalCmd = evalCmd + '\n';
     }
 
+    debug('eval %j', evalCmd);
+    self.eval(evalCmd, self.context, 'repl', finish);
+
     function finish(e, ret) {
       debug('finish', e, ret);
       self.memory(cmd);