refactor(core): CORE-01 migrate utility contracts to TypeScript

packages/artplayer/src/utils/property.ts

@@ -0,0 +1,35 @@
+export const def = Object.defineProperty
+
+const { hasOwnProperty } = Object.prototype
+export function has(obj: object, name: PropertyKey): boolean {
+  return hasOwnProperty.call(obj, name)
+}
+
+export function get(obj: object, name: PropertyKey): PropertyDescriptor | undefined {
+  return Object.getOwnPropertyDescriptor(obj, name)
+}
+
+export function mergeDeep<T extends object[]>(...objects: T): T[number] {
+  const isObject = (item: unknown): item is Record<string, unknown> => !!item && typeof item === 'object' && !Array.isArray(item)
+  const result = objects.reduce<Record<string, unknown>>((prev, obj) => {
+    Object.keys(obj).forEach((key) => {
+      const pVal = prev[key]
+      const oVal: unknown = (obj as Record<string, unknown>)[key]
+      let value: unknown
+      if (Array.isArray(pVal) && Array.isArray(oVal)) {
+        value = pVal.concat(...oVal)
+      }
+      else if (isObject(pVal) && isObject(oVal)) {
+        value = mergeDeep(pVal, oVal)
+      }
+      else {
+        value = oVal
+      }
+      // Treat keys as data rather than invoking inherited setters such as __proto__.
+      def(prev, key, { value, enumerable: true, configurable: true, writable: true })
+    })
+    return prev
+  }, {})
+  // Preserve the existing generic API; dynamic keys are handled only inside this boundary.
+  return result as T[number]
+}