feat(compiler-vapor): support v-on for component (#175)

Co-authored-by: Kevin Deng 三咲智子 <sxzz@sxzz.moe>

packages/compiler-vapor/__tests__/generators/__snapshots__/component.spec.ts.snap

@@ -1,5 +1,20 @@
 // Vitest Snapshot v1, https://vitest.dev/guide/snapshot.html
 
+exports[`generate component > generate component with emits 1`] = `
+"import { toHandlerKey as _toHandlerKey } from 'vue';
+import { resolveComponent as _resolveComponent, createComponent as _createComponent } from 'vue/vapor';
+
+export function render(_ctx) {
+  const n0 = _createComponent(_resolveComponent("Comp"), [{
+    onClick: () => (fn)
+  }])
+  const n1 = _createComponent(_resolveComponent("Comp"), [{
+    [_toHandlerKey(eventName)]: () => (fn)
+  }])
+  return [n0, n1]
+}"
+`;
+
 exports[`generate component > generate multi root component 1`] = `
 "import { resolveComponent as _resolveComponent, createComponent as _createComponent, template as _template } from 'vue/vapor';
 const t0 = _template("123")

packages/compiler-vapor/__tests__/generators/component.spec.ts

@@ -20,4 +20,12 @@ describe('generate component', () => {
     const { code } = compile(`<div><Comp/></div>`)
     expect(code).toMatchSnapshot()
   })
+
+  test('generate component with emits', () => {
+    const { code } = compile(`
+    <Comp @click="fn" />
+    <Comp @[eventName]="fn" />
+    `)
+    expect(code).toMatchSnapshot()
+  })
 })

packages/compiler-vapor/src/generators/prop.ts

@@ -86,7 +86,7 @@ function genLiteralObjectProps(
 }
 
 export function genPropKey(
-  { key: node, runtimeCamelize, modifier }: IRProp,
+  { key: node, modifier, runtimeCamelize, runtimeHandler }: IRProp,
   context: CodegenContext,
 ): CodeFragment[] {
   const { helper } = context
@@ -104,13 +104,14 @@ export function genPropKey(
     ]
   }
 
-  const key = genExpression(node, context)
-  return [
-    '[',
-    modifier && `${JSON.stringify(modifier)} + `,
-    ...(runtimeCamelize ? genCall(helper('camelize'), key) : key),
-    ']',
-  ]
+  let key = genExpression(node, context)
+  if (runtimeCamelize) {
+    key = genCall(helper('camelize'), key)
+  }
+  if (runtimeHandler) {
+    key = genCall(helper('toHandlerKey'), key)
+  }
+  return ['[', modifier && `${JSON.stringify(modifier)} + `, ...key, ']']
 }
 
 function genPropValue(values: SimpleExpressionNode[], context: CodegenContext) {

packages/compiler-vapor/src/transform.ts

@@ -43,6 +43,7 @@ export interface DirectiveTransformResult {
   value: SimpleExpressionNode
   modifier?: '.' | '^'
   runtimeCamelize?: boolean
+  runtimeHandler?: boolean
 }
 
 // A structural directive transform is technically also a NodeTransform;

packages/compiler-vapor/src/transforms/vOn.ts

@@ -1,9 +1,14 @@
-import { ErrorCodes, createCompilerError } from '@vue/compiler-dom'
+import {
+  ElementTypes,
+  ErrorCodes,
+  createCompilerError,
+} from '@vue/compiler-dom'
 import type { DirectiveTransform } from '../transform'
 import { IRNodeTypes, type KeyOverride, type SetEventIRNode } from '../ir'
 import { resolveModifiers } from '@vue/compiler-dom'
-import { extend, makeMap } from '@vue/shared'
+import { extend, makeMap, toHandlerKey } from '@vue/shared'
 import { resolveExpression } from '../utils'
+import { EMPTY_EXPRESSION } from './utils'
 
 const delegatedEvents = /*#__PURE__*/ makeMap(
   'beforeinput,click,dblclick,contextmenu,focusin,focusout,input,keydown,' +
@@ -14,6 +19,8 @@ const delegatedEvents = /*#__PURE__*/ makeMap(
 
 export const transformVOn: DirectiveTransform = (dir, node, context) => {
   let { arg, exp, loc, modifiers } = dir
+  const isComponent = node.tagType === ElementTypes.COMPONENT
+
   if (!exp && (!modifiers.length || !arg)) {
     context.options.onError(
       createCompilerError(ErrorCodes.X_V_ON_NO_EXPRESSION, loc),
@@ -70,6 +77,18 @@ export const transformVOn: DirectiveTransform = (dir, node, context) => {
     }
   }
 
+  if (isComponent) {
+    if (arg.isStatic) {
+      arg = extend({}, arg, { content: toHandlerKey(arg.content) })
+    }
+    const handler = exp || EMPTY_EXPRESSION
+    return {
+      key: arg,
+      value: handler,
+      runtimeHandler: !arg.isStatic,
+    }
+  }
+
   const operation: SetEventIRNode = {
     type: IRNodeTypes.SET_EVENT,
     element: context.reference(),