chore: minor tweaks

Author: yyx990803

packages/reactivity/src/watch.ts

@@ -50,10 +50,13 @@ export interface WatchOptions<Immediate = boolean> extends DebuggerOptions {
   scheduler?: WatchScheduler
   onWarn?: (msg: string, ...args: any[]) => void
   /**
+   * Augment callback as scheduler job for special handling in core scheduler
    * @internal
    */
   augmentJob?: (job: (...args: any[]) => void) => void
   /**
+   * Call a user-provided callback with error handling
+   * runtime-core will pass `callWithAsyncErrorHandling` with instance
    * @internal
    */
   call?: (
@@ -137,9 +140,9 @@ export function watch(
   }
 
   let effect: ReactiveEffect
-  let boundCleanup: typeof onWatcherCleanup
   let getter: () => any
   let cleanup: (() => void) | undefined
+  let boundCleanup: typeof onWatcherCleanup // `onCleanup` passed to callbacks
   let forceTrigger = false
   let isMultiSource = false
 
@@ -277,12 +280,9 @@ export function watch(
   }
 
   effect = new ReactiveEffect(getter)
-  boundCleanup = fn => onWatcherCleanup(fn, false, effect)
-  if (scheduler) {
-    effect.scheduler = () => scheduler(job, false)
-  } else {
-    effect.scheduler = job as EffectScheduler
-  }
+  effect.scheduler = scheduler
+    ? () => scheduler(job, false)
+    : (job as EffectScheduler)
 
   cleanup = effect.onStop = () => {
     const cleanups = cleanupMap.get(effect)
@@ -296,6 +296,8 @@ export function watch(
     }
   }
 
+  boundCleanup = fn => onWatcherCleanup(fn, false, effect)
+
   if (__DEV__) {
     effect.onTrack = options.onTrack
     effect.onTrigger = options.onTrigger

packages/runtime-core/src/apiWatch.ts

@@ -172,7 +172,9 @@ function doWatch(
 
   const baseWatchOptions: BaseWatchOptions = extend({}, options)
 
-  if (__DEV__) baseWatchOptions.onWarn = warn
+  if (__DEV__) {
+    baseWatchOptions.onWarn = warn
+  }
 
   let ssrCleanup: (() => void)[] | undefined
   if (__SSR__ && isInSSRComponentSetup) {