fix: child data cannot sync to parent in some case

dist/regular.js

@@ -880,7 +880,7 @@ return /******/ (function(modules) { // webpackBootstrap
 	  }
 	  return paramObj;
 	}
-	_.eventReg = /^on-(\w[-\w]+)$/;
+	_.eventReg = /^on-(\w[-\w]*)$/;
 
 	_.toText = function(obj){
 	  return obj == null ? "": "" + obj;
@@ -4906,12 +4906,16 @@ return /******/ (function(modules) { // webpackBootstrap
 	      value = self._touchExpr(value);
 	      // use bit operate to control scope
 	      if( !(isolate & 2) )
+	        // sync data from parent to child
 	        this.$watch(value, (function(name, val){
 	          this.data[name] = val;
 	        }).bind(component, name), OPTIONS.SYNC)
 	      if( value.set && !(isolate & 1 ) )
-	        // sync the data. it force the component don't trigger attr.name's first dirty echeck
-	        component.$watch(name, self.$update.bind(self, value), OPTIONS.INIT);
+	        // sync data from child to parent. it force the component don't trigger attr.name's first dirty echeck
+	        component.$watch(name, self.$update.bind(self, value), {
+	          init: true,
+	          last: this.data[ name ]
+	        });
 	    }
 	  }
 	  if(is && is.type === 'expression'  ){

lib/walkers.js

@@ -713,12 +713,16 @@ walkers.component = function(ast, options){
       value = self._touchExpr(value);
       // use bit operate to control scope
       if( !(isolate & 2) )
+        // sync data from parent to child
         this.$watch(value, (function(name, val){
           this.data[name] = val;
         }).bind(component, name), OPTIONS.SYNC)
       if( value.set && !(isolate & 1 ) )
-        // sync the data. it force the component don't trigger attr.name's first dirty echeck
-        component.$watch(name, self.$update.bind(self, value), OPTIONS.INIT);
+        // sync data from child to parent. it force the component don't trigger attr.name's first dirty echeck
+        component.$watch(name, self.$update.bind(self, value), {
+          init: true,
+          last: this.data[ name ]
+        });
     }
   }
   if(is && is.type === 'expression'  ){

test/spec/browser-bugfix.js

@@ -1433,4 +1433,50 @@ it('bugfix #50', function(){
     })
   })
 
+  describe("M 0.6.3", function(){
+    it('bugfix#235 - should sync data from child to parent with string', function(){
+      var Child = Regular.extend({
+        template: '{ foo }',
+        init: function() {
+          this.data.foo = 'changed'
+        },
+      });
+
+      var Parent = Regular.extend({
+        template: '{foo}\n<Child foo="{ foo }"></Child>',
+        config: function() {
+          this.data.foo = 'bar'
+        }
+      });
+
+      Parent.component('Child', Child);
+
+      var parent = new Parent();
+
+      expect(parent.data.foo).to.equal('changed');
+    })
+
+    it('bugfix#235 - should sync data from child to parent with undefined', function(){
+      var Child = Regular.extend({
+        template: '{ foo }',
+        init: function() {
+          this.data.foo = undefined
+        },
+      });
+
+      var Parent = Regular.extend({
+        template: '{foo}\n<Child foo="{ foo }"></Child>',
+        config: function() {
+          this.data.foo = 'bar'
+        }
+      });
+
+      Parent.component('Child', Child);
+
+      var parent = new Parent()
+
+      expect(parent.data.foo).to.equal(undefined);
+    })
+  })
+
 })