address Discussion/#96: ensure correct mixin resolution order

Author: yyx990803

src/util/merge-option.js

@@ -234,25 +234,22 @@ module.exports = function mergeOptions (parent, child, vm) {
   guardComponents(child.components)
   var options = {}
   var key
+  if (child.mixins) {
+    for (var i = 0, l = child.mixins.length; i < l; i++) {
+      parent = mergeOptions(parent, child.mixins[i], vm)
+    }
+  }
   for (key in parent) {
-    merge(parent[key], child[key], key)
+    merge(key)
   }
   for (key in child) {
     if (!(parent.hasOwnProperty(key))) {
-      merge(parent[key], child[key], key)
-    }
-  }
-  var mixins = child.mixins
-  if (mixins) {
-    for (var i = 0, l = mixins.length; i < l; i++) {
-      for (key in mixins[i]) {
-        merge(options[key], mixins[i][key], key)
-      }
+      merge(key)
     }
   }
-  function merge (parentVal, childVal, key) {
+  function merge (key) {
     var strat = strats[key] || defaultStrat
-    options[key] = strat(parentVal, childVal, vm, key)
+    options[key] = strat(parent[key], child[key], vm, key)
   }
   return options
 }

test/unit/specs/util/merge-option_spec.js

@@ -255,18 +255,26 @@ describe('Util - Option merging', function () {
 
   it('mixins', function () {
     var a = {}, b = {}, c = {}, d = {}
-    var mixinA = { a: 1, directives: { a: a } }
-    var mixinB = { b: 1, directives: { b: b } }
+    var f1 = function () {}
+    var f2 = function () {}
+    var f3 = function () {}
+    var f4 = function () {}
+    var mixinA = { a: 1, directives: { a: a }, created: f2 }
+    var mixinB = { b: 1, directives: { b: b }, created: f3 }
     var res = merge(
-      { a: 2, directives: { c: c } },
-      { directives: { d: d }, mixins: [mixinA, mixinB] }
+      { a: 2, directives: { c: c }, created: [f1] },
+      { directives: { d: d }, mixins: [mixinA, mixinB], created: f4 }
     )
     expect(res.a).toBe(1)
     expect(res.b).toBe(1)
     expect(res.directives.a).toBe(a)
     expect(res.directives.b).toBe(b)
     expect(res.directives.c).toBe(c)
     expect(res.directives.d).toBe(d)
+    expect(res.created[0]).toBe(f1)
+    expect(res.created[1]).toBe(f2)
+    expect(res.created[2]).toBe(f3)
+    expect(res.created[3]).toBe(f4)
   })
 
 })