Fix to prevent an options validator being added on every step submission

This is an initial fix for issue #42. For 'options' fields the form controller adds a validator to check that the chosen option is one of the defined set of options for the field. Rather than adding this validator on each form submission, this change adds it once on start up.

- Moves the equality validator on 'options' outside of the function return
- Unit test added for the updated code, and others cleaned up slightly.

lib/validation/index.js

@@ -30,6 +30,24 @@ function applyValidator(validator, value, key) {
 }
 
 function validator(fields) {
+
+    _.each(fields, function (field, key) {
+        fields[key].validate = fields[key].validate || [];
+
+        if (typeof fields[key].validate === 'string') {
+            fields[key].validate = [fields[key].validate];
+        }
+
+        if (fields[key].options) {
+            fields[key].validate.push({
+                type: 'equal',
+                arguments: _.map(fields[key].options, function (o) {
+                    return typeof o === 'string' ? o : o.value;
+                })
+            });
+        }
+    });
+
     return function (key, value, values, emptyValue) {
         emptyValue = emptyValue === undefined ? '' : emptyValue;
 
@@ -50,25 +68,9 @@ function validator(fields) {
         }
 
         if (fields[key]) {
-            fields[key].validate = fields[key].validate || [];
             if (shouldValidate()) {
-                var f = fields[key].validate;
-
-                if (typeof f === 'string') {
-                    f = [f];
-                }
-
-                if (fields[key].options) {
-                    f.push({
-                        type: 'equal',
-                        arguments: _.map(fields[key].options, function (o) {
-                            return typeof o === 'string' ? o : o.value;
-                        })
-                    });
-                }
-
                 debug('Applying validation on field %s with %s', key, value);
-                return _.reduce(f, function (err, validator) {
+                return _.reduce(fields[key].validate, function (err, validator) {
                     return err || applyValidator(validator, value, key);
                 }, null);
             } else {

test/spec/spec.form.js

@@ -21,13 +21,20 @@ describe('Form Controller', function () {
         form.should.be.an.instanceOf(EventEmitter);
     });
 
-    it('throws if both template is undefined', function () {
+    it('throws if template is undefined', function () {
         var fn = function () {
             return new Form({});
         };
         fn.should.throw();
     });
 
+    it('throws if options are undefined', function () {
+        var fn = function () {
+            return new Form();
+        };
+        fn.should.throw();
+    });
+
     it('has `get` and `post` methods', function () {
         var form = new Form({ template: 'index' });
         form.get.should.be.a('function');
@@ -303,7 +310,7 @@ describe('Form Controller', function () {
             cb.should.have.been.calledWithExactly(new Error('Undefined validator:unknown'));
         });
 
-        it('ignores an unkown formatter', function () {
+        it('ignores an unknown formatter', function () {
             var form = new Form({
                 template: 'index',
                 fields: {
@@ -332,7 +339,7 @@ describe('Form Controller', function () {
             form.setErrors.should.have.been.calledWithExactly(null, req, res);
         });
 
-        it('call callback with error if _process fails', function () {
+        it('calls callback with error if _process fails', function () {
             var cb = sinon.stub();
             sinon.stub(form, '_process').yields('error');
             form.post(req, res, cb);
@@ -383,6 +390,17 @@ describe('Form Controller', function () {
             validators.equal.should.have.been.calledWith('number', 'one', 'two', 'three');
         });
 
+        it('does not keep adding equality validators if one already exists', function () {
+            req.body = {
+                options: 'number'
+            };
+            form.post(req, res, cb);
+            validators.equal.should.have.been.calledOnce;
+            form.post(req, res, cb);
+            validators.equal.should.have.been.calledTwice;
+            form.options.fields['options'].validate.length.should.equal(1);
+        });
+
         it('calls out to form.validate', function () {
             form.post(req, res, cb);
             form.validate.should.have.been.calledWith(req, res);