fix(runtime-core): force evalutating SetupContext type (fix vuejs#2362)

sapphi-red · Dec 14, 2020 · 1383f6e · 1383f6e
1 parent 3ca7336
commit 1383f6e
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Showing 2 changed files with 20 additions and 7 deletions.
diff --git a/packages/runtime-core/src/component.ts b/packages/runtime-core/src/component.ts
@@ -167,12 +167,15 @@ export const enum LifecycleHooks {
   ERROR_CAPTURED = 'ec'
 }
 
-export interface SetupContext<E = EmitsOptions> {
-  attrs: Data
-  slots: Slots
-  emit: EmitFn<E>
-  expose: (exposed: Record<string, any>) => void
-}
+// use `E extends any` to force evaluating type to fix #2362
+export type SetupContext<E = EmitsOptions> = E extends any
+  ? {
+      attrs: Data
+      slots: Slots
+      emit: EmitFn<E>
+      expose: (exposed: Record<string, any>) => void
+    }
+  : never
 
 /**
  * @internal

diff --git a/test-dts/component.test-d.ts b/test-dts/component.test-d.ts
@@ -9,7 +9,9 @@ import {
   expectType,
   ShallowUnwrapRef,
   FunctionalComponent,
-  ComponentPublicInstance
+  ComponentPublicInstance,
+  SetupContext,
+  expectAssignable
 } from './index'
 
 declare function extractComponentOptions<Props, RawBindings>(
@@ -423,3 +425,11 @@ describe('class', () => {
 
   expectType<number>(props.foo)
 })
+
+describe('SetupContext', () => {
+  describe('can assign', () => {
+    const wider: SetupContext<{ a: () => true; b: () => true }> = {} as any
+
+    expectAssignable<SetupContext<{ b: () => true }>>(wider)
+  })
+})