allow data to be undefined

src/compiler/codegen/index.js

@@ -23,7 +23,7 @@ function genElement (el) {
     // if the element is potentially a component,
     // wrap its children as a thunk.
     const children = genChildren(el, !isReservedTag(el.tag))
-    return `__h__('${el.tag}', ${genData(el)}, ${children})`
+    return `__h__('${el.tag}', ${genData(el)}, ${children}, ${el.svg})`
   }
 }
 
@@ -52,7 +52,7 @@ function genFor (el) {
 
 function genData (el) {
   if (el.plain) {
-    return el.svg ? '{svg:true}' : '{}'
+    return 'undefined'
   }
 
   let data = '{'
@@ -63,11 +63,6 @@ function genData (el) {
     let dirs = genDirectives(el)
     if (dirs) data += dirs + ','
   }
-
-  // svg
-  if (el.svg) {
-    data += 'svg:true,'
-  }
   // pre
   if (el.pre) {
     data += 'pre:true,'

src/compiler/parser/index.js

@@ -64,7 +64,6 @@ export function parse (template, options) {
       tag = tag.toLowerCase()
       const element = {
         tag,
-        plain: !attrs.length,
         attrsList: attrs,
         attrsMap: makeAttrsMap(attrs),
         parent: currentParent,
@@ -91,6 +90,9 @@ export function parse (template, options) {
       } else {
         processFor(element)
         processIf(element)
+        // determine whether this is a plain element after
+        // removing if/for attributes
+        element.plain = !attrs.length
         processRender(element)
         processSlot(element)
         processComponent(element)

src/runtime/dom/modules/class.js

@@ -10,11 +10,12 @@ function updateClass (oldVnode, vnode) {
 
   // check if this is a component container node
   // or a child component root node
-  if (vnode.child) {
-    data = mergeClassData(vnode.child._vnode.data, data)
+  let i
+  if ((i = vnode.child) && (i = i._vnode.data)) {
+    data = mergeClassData(i, data)
   }
-  if (vnode.parent) {
-    data = mergeClassData(data, vnode.parent.data)
+  if ((i = vnode.parent) && (i = i.data)) {
+    data = mergeClassData(data, i)
   }
 
   let cls = genClass(data)

src/runtime/vdom/create-component.js

@@ -40,6 +40,8 @@ export function createComponent (Ctor, data, parent, children) {
     }
   }
 
+  data = data || {}
+
   // merge component management hooks onto the placeholder node
   mergeHooks(data)
 

src/runtime/vdom/create-element.js

@@ -4,19 +4,18 @@ import { flatten } from './helpers'
 import { renderState } from '../instance/render'
 import { warn, isReservedTag, isUnknownElement, resolveAsset } from '../util/index'
 
-export default function createElement (tag, data, children) {
-  data = data || {}
+export default function createElement (tag, data, children, svg) {
   const context = this
   const parent = renderState.activeInstance
   if (typeof tag === 'string') {
     let Ctor
     if (isReservedTag(tag)) {
-      return VNode(tag, data, flatten(children))
+      return VNode(tag, data, flatten(children), undefined, undefined, svg)
     } else if ((Ctor = resolveAsset(context.$options, 'components', tag))) {
       return createComponent(Ctor, data, parent, children)
     } else {
       if (process.env.NODE_ENV !== 'production') {
-        if (!data.svg && isUnknownElement(tag)) {
+        if (!svg && isUnknownElement(tag)) {
           warn(
             'Unknown custom element: <' + tag + '> - did you ' +
             'register the component correctly? For recursive components, ' +
@@ -24,7 +23,7 @@ export default function createElement (tag, data, children) {
           )
         }
       }
-      return VNode(tag, data, flatten(children && children()))
+      return VNode(tag, data, flatten(children && children()), undefined, undefined, svg)
     }
   } else {
     return createComponent(tag, data, parent, children)

src/runtime/vdom/patch.js

@@ -52,14 +52,18 @@ export default function createPatchFunction (backend) {
   function createRmCb (childElm, listeners) {
     function remove () {
       if (--remove.listeners === 0) {
-        const parent = nodeOps.parentNode(childElm)
-        nodeOps.removeChild(parent, childElm)
+        removeElement(childElm)
       }
     }
     remove.listeners = listeners
     return remove
   }
 
+  function removeElement (el) {
+    const parent = nodeOps.parentNode(el)
+    nodeOps.removeChild(parent, el)
+  }
+
   function createElm (vnode, insertedVnodeQueue) {
     let i, elm
     const data = vnode.data
@@ -77,7 +81,7 @@ export default function createPatchFunction (backend) {
     const children = vnode.children
     const tag = vnode.tag
     if (isDef(tag)) {
-      elm = vnode.elm = isDef(data) && data.svg
+      elm = vnode.elm = vnode.svg
         ? nodeOps.createSVGElement(tag)
         : nodeOps.createElement(tag)
       if (Array.isArray(children)) {
@@ -87,7 +91,9 @@ export default function createPatchFunction (backend) {
       } else if (isPrimitive(vnode.text)) {
         nodeOps.appendChild(elm, nodeOps.createTextNode(vnode.text))
       }
-      invokeCreateHooks(vnode, insertedVnodeQueue)
+      if (isDef(data)) {
+        invokeCreateHooks(vnode, insertedVnodeQueue)
+      }
     } else {
       elm = vnode.elm = nodeOps.createTextNode(vnode.text)
     }
@@ -134,7 +140,7 @@ export default function createPatchFunction (backend) {
       if (isDef(ch)) {
         if (isDef(ch.tag)) {
           invokeDestroyHook(ch)
-          invokeRemoveHook(ch)
+          removeAndInvokeRemoveHook(ch)
         } else { // Text node
           nodeOps.removeChild(parentElm, ch.elm)
         }
@@ -142,28 +148,31 @@ export default function createPatchFunction (backend) {
     }
   }
 
-  function invokeRemoveHook (vnode, rm) {
-    let i
-    let listeners = cbs.remove.length + 1
-    if (!rm) {
-      // directly removing
-      rm = createRmCb(vnode.elm, listeners)
-    } else {
-      // we have a recursively passed down rm callback
-      // increase the listeners count
-      rm.listeners += listeners
-    }
-    // recursively invoke hooks on child component nodes
-    if (isDef(i = vnode.child)) {
-      invokeRemoveHook(i._vnode, rm)
-    }
-    for (i = 0; i < cbs.remove.length; ++i) {
-      cbs.remove[i](vnode, rm)
-    }
-    if (isDef(i = vnode.data) && isDef(i = i.hook) && isDef(i = i.remove)) {
-      i(vnode, rm)
+  function removeAndInvokeRemoveHook (vnode, rm) {
+    if (rm || isDef(vnode.data)) {
+      let listeners = cbs.remove.length + 1
+      if (!rm) {
+        // directly removing
+        rm = createRmCb(vnode.elm, listeners)
+      } else {
+        // we have a recursively passed down rm callback
+        // increase the listeners count
+        rm.listeners += listeners
+      }
+      // recursively invoke hooks on child component root node
+      if (isDef(i = vnode.child) && isDef(i = i._vnode) && isDef(i.data)) {
+        removeAndInvokeRemoveHook(i, rm)
+      }
+      for (i = 0; i < cbs.remove.length; ++i) {
+        cbs.remove[i](vnode, rm)
+      }
+      if (isDef(i = vnode.data.hook) && isDef(i = i.remove)) {
+        i(vnode, rm)
+      } else {
+        rm()
+      }
     } else {
-      rm()
+      removeElement(vnode.elm)
     }
   }
 

src/runtime/vdom/vnode.js

@@ -1,10 +1,11 @@
-export default function VNode (tag, data, children, text, elm) {
+export default function VNode (tag, data, children, text, elm, svg) {
   return {
     tag,
     data,
     children,
     text,
     elm,
+    svg,
     key: data && data.key
   }
 }