feat(runtime-vapor): implement setupContext (#157)

packages/runtime-vapor/src/apiRender.ts

@@ -1,15 +1,22 @@
-import { isArray, isFunction, isObject } from '@vue/shared'
 import {
   type ComponentInternalInstance,
   componentKey,
+  createSetupContext,
   setCurrentInstance,
 } from './component'
 import { insert, querySelector, remove } from './dom/element'
 import { flushPostFlushCbs, queuePostRenderEffect } from './scheduler'
-import { proxyRefs } from '@vue/reactivity'
 import { invokeLifecycle } from './componentLifecycle'
 import { VaporLifecycleHooks } from './apiLifecycle'
+import {
+  pauseTracking,
+  proxyRefs,
+  resetTracking,
+  shallowReadonly,
+} from '@vue/reactivity'
+import { isArray, isFunction, isObject } from '@vue/shared'
 import { fallThroughAttrs } from './componentAttrs'
+import { VaporErrorCodes, callWithErrorHandling } from './errorHandling'
 
 export const fragmentKey = Symbol(__DEV__ ? `fragmentKey` : ``)
 
@@ -26,11 +33,22 @@ export function setupComponent(
 ): void {
   const reset = setCurrentInstance(instance)
   instance.scope.run(() => {
-    const { component, props, emit, attrs } = instance
+    const { component, props } = instance
-    const ctx = { expose: () => {}, emit, attrs }
 
     const setupFn = isFunction(component) ? component : component.setup
-    const stateOrNode = setupFn && setupFn(props, ctx)
+    let stateOrNode: Block | undefined
+    if (setupFn) {
+      const setupContext = (instance.setupContext =
+        setupFn && setupFn.length > 1 ? createSetupContext(instance) : null)
+      pauseTracking()
+      stateOrNode = callWithErrorHandling(
+        setupFn,
+        instance,
+        VaporErrorCodes.SETUP_FUNCTION,
+        [__DEV__ ? shallowReadonly(props) : props, setupContext],
+      )
+      resetTracking()
+    }
 
     let block: Block | undefined
 

packages/runtime-vapor/src/component.ts

@@ -1,5 +1,5 @@
 import { EffectScope } from '@vue/reactivity'
-import { EMPTY_OBJ, isFunction } from '@vue/shared'
+import { EMPTY_OBJ, NOOP, isFunction } from '@vue/shared'
 import type { Block } from './apiRender'
 import type { DirectiveBinding } from './directives'
 import {
@@ -20,12 +20,48 @@ import {
 import { VaporLifecycleHooks } from './apiLifecycle'
 
 import type { Data } from '@vue/shared'
+import { warn } from './warning'
 
 export type Component = FunctionalComponent | ObjectComponent
 
-export type SetupFn = (props: any, ctx: any) => Block | Data | void
+export type SetupFn = (props: any, ctx: SetupContext) => Block | Data | void
 export type FunctionalComponent = SetupFn & Omit<ObjectComponent, 'setup'>
 
+export type SetupContext<E = EmitsOptions> = E extends any
+  ? {
+      attrs: Data
+      emit: EmitFn<E>
+      expose: (exposed?: Record<string, any>) => void
+      // TODO slots
+    }
+  : never
+
+export function createSetupContext(
+  instance: ComponentInternalInstance,
+): SetupContext {
+  if (__DEV__) {
+    // We use getters in dev in case libs like test-utils overwrite instance
+    // properties (overwrites should not be done in prod)
+    return Object.freeze({
+      get attrs() {
+        return getAttrsProxy(instance)
+      },
+      get emit() {
+        return (event: string, ...args: any[]) => instance.emit(event, ...args)
+      },
+      expose: NOOP,
+    })
+  } else {
+    return {
+      get attrs() {
+        return getAttrsProxy(instance)
+      },
+      emit: instance.emit,
+      expose: NOOP,
+    }
+  }
+}
+
 export interface ObjectComponent {
   props?: ComponentPropsOptions
   inheritAttrs?: boolean
@@ -59,12 +95,15 @@ export interface ComponentInternalInstance {
 
   // state
   setupState: Data
+  setupContext: SetupContext | null
   props: Data
   emit: EmitFn
   emitted: Record<string, boolean> | null
   attrs: Data
   refs: Data
 
+  attrsProxy: Data | null
+
   // lifecycle
   isMounted: boolean
   isUnmounted: boolean
@@ -169,12 +208,15 @@ export function createComponentInstance(
 
     // state
     setupState: EMPTY_OBJ,
+    setupContext: null,
     props: EMPTY_OBJ,
     emit: null!,
     emitted: null,
     attrs: EMPTY_OBJ,
     refs: EMPTY_OBJ,
 
+    attrsProxy: null,
+
     // lifecycle
     isMounted: false,
     isUnmounted: false,
@@ -234,3 +276,31 @@ export function createComponentInstance(
 
   return instance
 }
+
+function getAttrsProxy(instance: ComponentInternalInstance): Data {
+  return (
+    instance.attrsProxy ||
+    (instance.attrsProxy = new Proxy(
+      instance.attrs,
+      __DEV__
+        ? {
+            get(target, key: string) {
+              return target[key]
+            },
+            set() {
+              warn(`setupContext.attrs is readonly.`)
+              return false
+            },
+            deleteProperty() {
+              warn(`setupContext.attrs is readonly.`)
+              return false
+            },
+          }
+        : {
+            get(target, key: string) {
+              return target[key]
+            },
+          },
+    ))
+  )
+}