fix :class binding array syntax cleanup (fix vuejs#1458)

yyx990803 · yyx990803 · commit d7d73db6680b · 2015-10-22T16:41:57.000-04:00
diff --git a/src/directives/class.js b/src/directives/class.js
@@ -57,15 +57,15 @@ module.exports = {
         addClass(this.el, value[i])
       }
     }
-    this.prevKeys = value
+    this.prevKeys = value.slice()
   },
 
   cleanup: function (value) {
     if (this.prevKeys) {
       var i = this.prevKeys.length
       while (i--) {
         var key = this.prevKeys[i]
-        if (!value || !contains(value, key)) {
+        if (key && (!value || !contains(value, key))) {
           removeClass(this.el, key)
         }
       }
diff --git a/test/unit/specs/directives/class_spec.js b/test/unit/specs/directives/class_spec.js
@@ -59,8 +59,14 @@ if (_.inBrowser) {
       expect(el.className).toBe('a c d')
       dir.update()
       expect(el.className).toBe('a')
-      dir.update(['e', ''])
+      // test mutating array
+      var arr = ['e', '']
+      dir.update(arr)
       expect(el.className).toBe('a e')
+      arr.length = 0
+      arr.push('f')
+      dir.update(arr)
+      expect(el.className).toBe('a f')
     })
 
   })

Original file line number	Diff line number	Diff line change
`@@ -57,15 +57,15 @@ module.exports = {`
`57`	`57`	`addClass(this.el, value[i])`
`58`	`58`	`}`
`59`	`59`	`}`
`60`		`- this.prevKeys = value`
	`60`	`+ this.prevKeys = value.slice()`
`61`	`61`	`},`
`62`	`62`
`63`	`63`	`cleanup: function (value) {`
`64`	`64`	`if (this.prevKeys) {`
`65`	`65`	`var i = this.prevKeys.length`
`66`	`66`	`while (i--) {`
`67`	`67`	`var key = this.prevKeys[i]`
`68`		`- if (!value \|\| !contains(value, key)) {`
	`68`	`+ if (key && (!value \|\| !contains(value, key))) {`
`69`	`69`	`removeClass(this.el, key)`
`70`	`70`	`}`
`71`	`71`	`}`