refactor(reactivity): adjust APIs

BREAKING CHANGE: Reactivity APIs adjustments:

- `readonly` is now non-tracking if called on plain objects.
  `lock` and `unlock` have been removed. A `readonly` proxy can no
  longer be directly mutated. However, it can still wrap an already
  reactive object and track changes to the source reactive object.

- `isReactive` now only returns true for proxies created by `reactive`,
   or a `readonly` proxy that wraps a `reactive` proxy.

- A new utility `isProxy` is introduced, which returns true for both
  reactive or readonly proxies.

- `markNonReactive` has been renamed to `markRaw`.

packages/reactivity/src/index.ts

@@ -11,13 +11,14 @@ export {
 } from './ref'
 export {
   reactive,
-  isReactive,
-  shallowReactive,
   readonly,
+  isReactive,
   isReadonly,
+  isProxy,
+  shallowReactive,
   shallowReadonly,
-  toRaw,
-  markNonReactive
+  markRaw,
+  toRaw
 } from './reactive'
 export {
   computed,

packages/reactivity/src/reactive.ts

@@ -20,7 +20,7 @@ const readonlyToRaw = new WeakMap<any, any>()
 
 // WeakSets for values that are marked readonly or non-reactive during
 // observable creation.
-const nonReactiveValues = new WeakSet<any>()
+const rawValues = new WeakSet<any>()
 
 const collectionTypes = new Set<Function>([Set, Map, WeakMap, WeakSet])
 const isObservableType = /*#__PURE__*/ makeMap(
@@ -32,7 +32,7 @@ const canObserve = (value: any): boolean => {
     !value._isVue &&
     !value._isVNode &&
     isObservableType(toRawType(value)) &&
-    !nonReactiveValues.has(value) &&
+    !rawValues.has(value) &&
     !Object.isFrozen(value)
   )
 }
@@ -132,19 +132,24 @@ function createReactiveObject(
 }
 
 export function isReactive(value: unknown): boolean {
-  return reactiveToRaw.has(value) || readonlyToRaw.has(value)
+  value = readonlyToRaw.get(value) || value
+  return reactiveToRaw.has(value)
 }
 
 export function isReadonly(value: unknown): boolean {
   return readonlyToRaw.has(value)
 }
 
+export function isProxy(value: unknown): boolean {
+  return readonlyToRaw.has(value) || reactiveToRaw.has(value)
+}
+
 export function toRaw<T>(observed: T): T {
   observed = readonlyToRaw.get(observed) || observed
   return reactiveToRaw.get(observed) || observed
 }
 
-export function markNonReactive<T extends object>(value: T): T {
-  nonReactiveValues.add(value)
+export function markRaw<T extends object>(value: T): T {
+  rawValues.add(value)
   return value
 }

packages/reactivity/src/ref.ts

@@ -1,7 +1,7 @@
 import { track, trigger } from './effect'
 import { TrackOpTypes, TriggerOpTypes } from './operations'
 import { isObject } from '@vue/shared'
-import { reactive, isReactive } from './reactive'
+import { reactive, isProxy } from './reactive'
 import { ComputedRef } from './computed'
 import { CollectionTypes } from './collectionHandlers'
 
@@ -98,7 +98,7 @@ export function customRef<T>(factory: CustomRefFactory<T>): Ref<T> {
 export function toRefs<T extends object>(
   object: T
 ): { [K in keyof T]: Ref<T[K]> } {
-  if (__DEV__ && !isReactive(object)) {
+  if (__DEV__ && !isProxy(object)) {
     console.warn(`toRefs() expects a reactive object but received a plain one.`)
   }
   const ret: any = {}