fix: do not deep merge array data (#604)

Author: lchanmann

Diff for: packages/test-utils/src/wrapper.js

@@ -421,7 +421,8 @@ export default class Wrapper implements BaseWrapper {
     }
 
     Object.keys(data).forEach((key) => {
-      if (typeof data[key] === 'object' && data[key] !== null) {
+      if (typeof data[key] === 'object' && data[key] !== null &&
+						!Array.isArray(data[key])) {
         // $FlowIgnore : Problem with possibly null this.vm
         const newObj = merge(this.vm[key], data[key])
         // $FlowIgnore : Problem with possibly null this.vm

Diff for: test/specs/wrapper/setData.spec.js

@@ -178,4 +178,17 @@ describeWithShallowAndMount('setData', (mountingMethod) => {
     expect(wrapper.vm.anObject.propA.prop1).to.equal('a')
     expect(wrapper.vm.anObject.propA.prop2).to.equal('b')
   })
+
+  it('sets array data properly', () => {
+    const TestComponent = {
+      data: () => ({
+        items: [1, 2]
+      })
+    }
+    const wrapper = mountingMethod(TestComponent)
+    wrapper.setData({
+      items: [3]
+    })
+    expect(wrapper.vm.items).to.deep.equal([3])
+  })
 })