add isPlainES6Map()

mobxjs · Jun 28, 2024 · 103d4b0 · 103d4b0
1 parent 5881536
commit 103d4b0
Show file tree

Hide file tree

Showing 2 changed files with 9 additions and 1 deletion.
diff --git a/packages/mobx/src/types/observablemap.ts b/packages/mobx/src/types/observablemap.ts
@@ -16,6 +16,7 @@ import {
     hasListeners,
     interceptChange,
     isES6Map,
+    isPlainES6Map,
     isPlainObject,
     isSpyEnabled,
     makeIterable,
@@ -351,7 +352,7 @@ export class ObservableMap<K = any, V = any>
             } else if (Array.isArray(other)) {
                 other.forEach(([key, value]) => this.set(key, value))
             } else if (isES6Map(other)) {
-                if (other.constructor.name !== "Map") {
+                if (!isPlainES6Map(other)) {
                     die(19, other)
                 }
                 other.forEach((value, key) => this.set(key, value))

diff --git a/packages/mobx/src/utils/utils.ts b/packages/mobx/src/utils/utils.ts
@@ -144,6 +144,13 @@ export function isES6Map(thing: any): thing is Map<any, any> {
     return thing != null && Object.prototype.toString.call(thing) === "[object Map]"
 }
 
+export function isPlainES6Map(thing: Map<any, any>): boolean {
+    const mapProto = Object.getPrototypeOf(thing)
+    const objectProto = Object.getPrototypeOf(mapProto)
+    const nullProto = Object.getPrototypeOf(objectProto)
+    return nullProto === null
+}
+
 export function isES6Set(thing: any): thing is Set<any> {
     return thing != null && Object.prototype.toString.call(thing) === "[object Set]"
 }