From 1b09cfb5a8ba644443a7f087f5dbf5e023f41255 Mon Sep 17 00:00:00 2001
From: pikax <carlos@hypermob.co.uk>
Date: Thu, 15 Apr 2021 10:00:15 +0100
Subject: [PATCH 1/2] fix(type): infer parent as `this` on `nextTick` function

---
 packages/runtime-core/src/scheduler.ts |  6 +++---
 test-dts/defineComponent.test-d.tsx    | 19 +++++++++++++++++++
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/packages/runtime-core/src/scheduler.ts b/packages/runtime-core/src/scheduler.ts
index 372866c8093..b46353da38f 100644
--- a/packages/runtime-core/src/scheduler.ts
+++ b/packages/runtime-core/src/scheduler.ts
@@ -49,9 +49,9 @@ let currentPreFlushParentJob: SchedulerJob | null = null
 const RECURSION_LIMIT = 100
 type CountMap = Map<SchedulerJob | SchedulerCb, number>
 
-export function nextTick(
-  this: ComponentPublicInstance | void,
-  fn?: () => void
+export function nextTick<T = void>(
+  this: T,
+  fn?: (this: T) => void
 ): Promise<void> {
   const p = currentFlushPromise || resolvedPromise
   return fn ? p.then(this ? fn.bind(this) : fn) : p
diff --git a/test-dts/defineComponent.test-d.tsx b/test-dts/defineComponent.test-d.tsx
index ff04a0d6f3f..d7c35d8910e 100644
--- a/test-dts/defineComponent.test-d.tsx
+++ b/test-dts/defineComponent.test-d.tsx
@@ -893,6 +893,25 @@ describe('emits', () => {
       expectError(this.$emit('input'))
       //  @ts-expect-error
       expectError(this.$emit('input', 1))
+    },
+    mounted() {
+      // #3599
+      this.$nextTick(function() {
+        // this should be bound to this instance
+
+        this.$emit('click', 1)
+        this.$emit('input', 'foo')
+        //  @ts-expect-error
+        expectError(this.$emit('nope'))
+        //  @ts-expect-error
+        expectError(this.$emit('click'))
+        //  @ts-expect-error
+        expectError(this.$emit('click', 'foo'))
+        //  @ts-expect-error
+        expectError(this.$emit('input'))
+        //  @ts-expect-error
+        expectError(this.$emit('input', 1))
+      })
     }
   })
 

From 5063676771a0dafe5ad6fe2b5c84735b61e20fbb Mon Sep 17 00:00:00 2001
From: pikax <carlos@hypermob.co.uk>
Date: Thu, 15 Apr 2021 10:03:30 +0100
Subject: [PATCH 2/2] chore: remove unused import

---
 packages/runtime-core/src/scheduler.ts | 1 -
 1 file changed, 1 deletion(-)

diff --git a/packages/runtime-core/src/scheduler.ts b/packages/runtime-core/src/scheduler.ts
index b46353da38f..aa2d9f26e9d 100644
--- a/packages/runtime-core/src/scheduler.ts
+++ b/packages/runtime-core/src/scheduler.ts
@@ -1,6 +1,5 @@
 import { ErrorCodes, callWithErrorHandling } from './errorHandling'
 import { isArray } from '@vue/shared'
-import { ComponentPublicInstance } from './componentPublicInstance'
 
 export interface SchedulerJob {
   (): void