vue3-core/packages/compiler-ssr/src/transforms/ssrInjectFallthroughAttrs.ts

91 lines
2.4 KiB
TypeScript

import {
NodeTransform,
NodeTypes,
ElementTypes,
locStub,
createSimpleExpression,
RootNode,
TemplateChildNode,
ParentNode,
findDir,
isBuiltInType
} from '@vue/compiler-dom'
const filterChild = (node: ParentNode) =>
node.children.filter(n => n.type !== NodeTypes.COMMENT)
const hasSingleChild = (node: ParentNode): boolean =>
filterChild(node).length === 1
export const ssrInjectFallthroughAttrs: NodeTransform = (node, context) => {
// _attrs is provided as a function argument.
// mark it as a known identifier so that it doesn't get prefixed by
// transformExpression.
if (node.type === NodeTypes.ROOT) {
context.identifiers._attrs = 1
}
if (
node.type === NodeTypes.ELEMENT &&
node.tagType === ElementTypes.COMPONENT &&
(isBuiltInType(node.tag, 'Transition') ||
isBuiltInType(node.tag, 'KeepAlive'))
) {
const rootChildren = filterChild(context.root)
if (rootChildren.length === 1 && rootChildren[0] === node) {
if (hasSingleChild(node)) {
injectFallthroughAttrs(node.children[0])
}
return
}
}
const parent = context.parent
if (!parent || parent.type !== NodeTypes.ROOT) {
return
}
if (node.type === NodeTypes.IF_BRANCH && hasSingleChild(node)) {
// detect cases where the parent v-if is not the only root level node
let hasEncounteredIf = false
for (const c of filterChild(parent)) {
if (
c.type === NodeTypes.IF ||
(c.type === NodeTypes.ELEMENT && findDir(c, 'if'))
) {
// multiple root v-if
if (hasEncounteredIf) return
hasEncounteredIf = true
} else if (
// node before v-if
!hasEncounteredIf ||
// non else nodes
!(c.type === NodeTypes.ELEMENT && findDir(c, /else/, true))
) {
return
}
}
injectFallthroughAttrs(node.children[0])
} else if (hasSingleChild(parent)) {
injectFallthroughAttrs(node)
}
}
function injectFallthroughAttrs(node: RootNode | TemplateChildNode) {
if (
node.type === NodeTypes.ELEMENT &&
(node.tagType === ElementTypes.ELEMENT ||
node.tagType === ElementTypes.COMPONENT) &&
!findDir(node, 'for')
) {
node.props.push({
type: NodeTypes.DIRECTIVE,
name: 'bind',
arg: undefined,
exp: createSimpleExpression(`_attrs`, false),
modifiers: [],
loc: locStub
})
}
}