event order for 'on'

now if you have a nested 'on' declaration I will enforce the nested order.

Author: seebees

lib/vows.js

@@ -57,7 +57,8 @@ var Suite = require('./vows/suite').Suite;
 //
 function addVow(vow) {
     var batch = vow.batch,
-        event = vow.binding.context.event || 'success';
+        event = vow.binding.context.event || 'success'
+        self = this;
 
     batch.total ++;
     batch.vows.push(vow);
@@ -66,8 +67,8 @@ function addVow(vow) {
     this.on(event, function () {
         var args = Array.prototype.slice.call(arguments);
         // If the vow is a sub-event then we know it is an
-        // emited event.  So I don't muck with the arguments
-        // However the legacey behavior:
+        // emitted event.  So I don't muck with the arguments
+        // However the legacy behavior:
         // If the callback is expecting two or more arguments,
         // pass the error as the first (null) and the result after.
         if (!(this.ctx && this.ctx.isEvent) &&
@@ -95,7 +96,6 @@ function addVow(vow) {
         this._vowsEmitedEvents.hasOwnProperty(event)) {
         // make sure no one is messing with me
         if (Array.isArray(this._vowsEmitedEvents[event])) {
-            var self = this;
             // I don't think I need to optimize for one event,
             // I think it is more important to make sure I check the vow n times
             self._vowsEmitedEvents[event].forEach(function(args) {
@@ -115,6 +115,17 @@ function addVow(vow) {
             return output('pending');
         }
 
+        if (vow.binding.context.isEvent && vow.binding.context.after) {
+            var after = vow.binding.context.after;
+            // only need to check order.  I won't get here if the after event
+            // has never been emitted
+            if (self._vowsEmitedEventsOrder.indexOf(after) > 
+                self._vowsEmitedEventsOrder.indexOf(event)) {
+                output('broken', event + ' emitted before ' + after);
+                return;
+            }
+        }
+
         // Run the test, and try to catch `AssertionError`s and other exceptions;
         // increment counters accordingly.
         try {
@@ -210,6 +221,7 @@ vows.describe = function (subject) {
     // just in case someone emit's before I get to it
     this.options.Emitter.prototype.emit = function (event) {
         this._vowsEmitedEvents = this._vowsEmitedEvents || {};
+        this._vowsEmitedEventsOrder = this._vowsEmitedEventsOrder || [];
         // slice off the event
         var args = Array.prototype.slice.call(arguments, 1);
         // if multiple events are fired, add or push
@@ -218,6 +230,9 @@ vows.describe = function (subject) {
         } else {
             this._vowsEmitedEvents[event] = [args];
         }
+
+        // push the event onto a stack so I have an order
+        this._vowsEmitedEventsOrder.push(event);
         return oldEmit.apply(this, arguments);
     }
     this.suites.push(suite);

lib/vows/context.js

@@ -52,9 +52,17 @@ this.Context = function (vow, ctx, env) {
       this.name = vow.description = 'on';
     }
 
+    // if this is a sub-event context AND it's context was an event,
+    // then I must enforce event order.
+    // this will not do a good job of handling pin-pong events
+    if (this.name === 'on' && ctx.isEvent) {
+        this.after = ctx.name;
+    }
+
     if (ctx.name === 'on') {
         this.isEvent = true;
         this.event = this.name;
+        this.after = ctx.after;
     } else {
         this.isEvent = false;
         this.event = 'success';

test/vows-test.js

@@ -407,9 +407,12 @@ vows.describe("Vows with sub events").addBatch({
                     assert.strictEqual(ret, 'request_data');
                 },
                 on: {
-                    "end": {
-                        "will catch end, even if it is in empty nested in 'request'": function (ret) {
-                            assert.strictEqual(ret, 'end_data')
+                    on: {
+                        "end": {
+                            "will require that 'end' is emitted after 'request'": function (ret) {
+                                assert.strictEqual(ret, 'end_data');
+                                // TODO need a test that fails to prove this works
+                            }
                         }
                     }
                 }