Updating nexpect to emit events. Fixes nodejitsu#14

This allows nexpect to work with conditional branching. It will
emit 'wait' right now, and the data will be the line of output
which matches the expected output. From there, you can re-test the data
and call sendline, expect, or wait again. Note that the user MUST
call wait BEFORE the end of the stackframe on which the child was spawned.

README.md

@@ -129,6 +129,25 @@ Lets take a look at some sample usage:
              console.log(err)
            }
          });
+
+  emitter = nexpect.spawn("node --interactive")
+         .run(function (err) {
+           if (!err) {
+             console.log("node process started, console logged, process exited");
+           }
+           else {
+             console.log(err)
+           }
+         });
+         emitter.expect(">");
+         emitter.on('wait',function(data){
+           if(data === '>'){
+             emitter.sendline("console.log('testing')")
+             .expect("testing")
+           } else if(data === 'testing') {
+             emitter.sendline("process.exit()")
+           }
+         });
 ```
 
 If you are looking for more examples take a look at the [examples][2], and [tests][3].

lib/nexpect.js

@@ -8,6 +8,7 @@
 var spawn = require('child_process').spawn;
 var util = require('util');
 var AssertionError = require('assert').AssertionError;
+var EventEmitter = require('events').EventEmitter;
 
 function chain (context) {
   return {
@@ -36,6 +37,9 @@ function chain (context) {
       context.queue.push(_wait);
       return chain(context);
     },
+    on: function() {
+        context.on.apply(this, arguments);
+    },
     sendline: function (line) {
       var _sendline = function _sendline () {
         context.process.stdin.write(line + '\n');
@@ -146,6 +150,7 @@ function chain (context) {
           // If this is an `_expect` function, then evaluate it and attempt
           // to evaluate the next function (in case it is a `_sendline` function).
           //
+          context.emit('expect');
           return currentFn(data) === true ?
             evalContext(data, '_expect') :
             onError(createExpectationError(currentFn.expectation, data), true);
@@ -156,6 +161,7 @@ function chain (context) {
           // then evaluate the function (in case it is a `_sendline` function).
           //
           if (currentFn(data) === true) {
+            context.emit('wait',data);
             context.queue.shift();
             evalContext(data, '_expect');
           }
@@ -295,7 +301,7 @@ function chain (context) {
         callback(null, stdout, signal || code);
       });
 
-      return context.process;
+      return context;
     }
   };
 }
@@ -366,6 +372,14 @@ function nspawn (command, params, options) {
     stripColors: options.stripColors,
     verbose: options.verbose
   };
+  _emitter = new EventEmitter();
+  context._emitter = _emitter;
+  context.on = function(){
+    _emitter.on.apply(_emitter,arguments);
+  };
+  context.emit = function(){
+    _emitter.emit.apply(_emitter,arguments);
+  };
 
   return chain(context);
 }

test/nexpect-test.js

@@ -61,6 +61,23 @@ vows.describe('nexpect').addBatch({
               .expect("testing")
               .sendline("process.exit()")
       ),
+      "and using the event driven method": {
+          "should respond with no error": function () {
+            child = nexpect.spawn('node', ['--interactive']);
+            child.run(function(err,stdout,exitcode){
+                assert.isTrue(!err);
+                assert.isArray(stdout);
+            });
+            child.on('wait',function(data){
+                if(data === '>'){
+                    child.sendline('console.log("testing")').wait('testing');
+                } else if (data === 'testing'){
+                    child.sendline('process.exit()');
+                }
+            });
+            child.wait('>');
+        }
+      },
       "and using the expect() method": {
         "when RegExp expectation is met": assertSpawn(
           nexpect.spawn("echo", ["hello"])