refactor: tidy up compiler

src/compiler/codegen/index.ts

@@ -477,13 +477,13 @@ function hash(str) {
 }
 
 function containsSlotChild(el: ASTNode): boolean {
-  if (el.type === 1) {
-    if (el.tag === 'slot') {
-      return true
-    }
-    return el.children.some(containsSlotChild)
+  if (el.type !== 1) {
+    return false
+  }
+  if (el.tag === 'slot') {
+    return true
   }
-  return false
+  return el.children.some(containsSlotChild)
 }
 
 function genScopedSlot(el: ASTElement, state: CodegenState): string {
@@ -518,30 +518,31 @@ export function genChildren(
   altGenNode?: Function
 ): string | void {
   const children = el.children
-  if (children.length) {
-    const el: any = children[0]
-    // optimize single v-for
-    if (
-      children.length === 1 &&
-      el.for &&
-      el.tag !== 'template' &&
-      el.tag !== 'slot'
-    ) {
-      const normalizationType = checkSkip
-        ? state.maybeComponent(el)
-          ? `,1`
-          : `,0`
-        : ``
-      return `${(altGenElement || genElement)(el, state)}${normalizationType}`
-    }
-    const normalizationType = checkSkip
-      ? getNormalizationType(children, state.maybeComponent)
-      : 0
-    const gen = altGenNode || genNode
-    return `[${children.map(c => gen(c, state)).join(',')}]${
-      normalizationType ? `,${normalizationType}` : ''
-    }`
+  if (!children.length) {
+    return
   }
+  const child: any = children[0]
+  // optimize single v-for
+  if (
+    children.length === 1 &&
+    child.for &&
+    child.tag !== 'template' &&
+    child.tag !== 'slot'
+  ) {
+    const normalizationType = checkSkip
+      ? state.maybeComponent(child)
+        ? `,1`
+        : `,0`
+      : ``
+    return `${(altGenElement || genElement)(child, state)}${normalizationType}`
+  }
+  const normalizationType = checkSkip
+    ? getNormalizationType(children, state.maybeComponent)
+    : 0
+  const gen = altGenNode || genNode
+  return `[${children.map(c => gen(c, state)).join(',')}]${
+    normalizationType ? `,${normalizationType}` : ''
+  }`
 }
 
 // determine the normalization needed for the children array.

src/compiler/optimizer.ts

@@ -70,32 +70,33 @@ function markStatic(node: ASTNode) {
 }
 
 function markStaticRoots(node: ASTNode, isInFor: boolean) {
-  if (node.type === 1) {
-    if (node.static || node.once) {
-      node.staticInFor = isInFor
-    }
-    // For a node to qualify as a static root, it should have children that
-    // are not just static text. Otherwise the cost of hoisting out will
-    // outweigh the benefits and it's better off to just always render it fresh.
-    if (
-      node.static &&
-      node.children.length &&
-      !(node.children.length === 1 && node.children[0].type === 3)
-    ) {
-      node.staticRoot = true
-      return
-    } else {
-      node.staticRoot = false
-    }
-    if (node.children) {
-      for (let i = 0, l = node.children.length; i < l; i++) {
-        markStaticRoots(node.children[i], isInFor || !!node.for)
-      }
+  if (node.type !== 1) {
+    return
+  }
+  if (node.static || node.once) {
+    node.staticInFor = isInFor
+  }
+  // For a node to qualify as a static root, it should have children that
+  // are not just static text. Otherwise the cost of hoisting out will
+  // outweigh the benefits and it's better off to just always render it fresh.
+  if (
+    node.static &&
+    node.children.length &&
+    !(node.children.length === 1 && node.children[0].type === 3)
+  ) {
+    node.staticRoot = true
+    return
+  } else {
+    node.staticRoot = false
+  }
+  if (node.children) {
+    for (let i = 0, l = node.children.length; i < l; i++) {
+      markStaticRoots(node.children[i], isInFor || !!node.for)
     }
-    if (node.ifConditions) {
-      for (let i = 1, l = node.ifConditions.length; i < l; i++) {
-        markStaticRoots(node.ifConditions[i].block, isInFor)
-      }
+  }
+  if (node.ifConditions) {
+    for (let i = 1, l = node.ifConditions.length; i < l; i++) {
+      markStaticRoots(node.ifConditions[i].block, isInFor)
     }
   }
 }