feat: class inherit method

packages/x6/src/util/object/inherit.ts

@@ -0,0 +1,83 @@
+/**
+ * @see https://www.typescriptlang.org/docs/handbook/mixins.html
+ */
+export function applyMixins(derivedCtor: any, ...baseCtors: any[]) {
+  baseCtors.forEach(baseCtor => {
+    Object.getOwnPropertyNames(baseCtor.prototype).forEach(name => {
+      Object.defineProperty(
+        derivedCtor.prototype,
+        name,
+        Object.getOwnPropertyDescriptor(baseCtor.prototype, name)!,
+      )
+    })
+  })
+}
+
+const extendStatics =
+  Object.setPrototypeOf ||
+  ({ __proto__: [] } instanceof Array &&
+    function(d, b) {
+      d.__proto__ = b
+    }) ||
+  function(d, b) {
+    for (const p in b) {
+      if (b.hasOwnProperty(p)) {
+        d[p] = (b as any)[p]
+      }
+    }
+  }
+
+/**
+ * @see https://github.com/microsoft/TypeScript/blob/5c85febb0ce9d6088cbe9b09cb42f73f9ee8ea05/src/compiler/transformers/es2015.ts#L4309
+ */
+export function inherit(cls: Function, base: Function) {
+  extendStatics(cls, base)
+  function tmp() {
+    this.constructor = cls
+  }
+  cls.prototype =
+    base === null
+      ? Object.create(base)
+      : ((tmp.prototype = base.prototype), new (tmp as any)())
+}
+
+let seed = 0
+const classIdMap = new WeakMap<Function, string>()
+function getClassId(c: Function) {
+  let id = classIdMap.get(c)
+  if (id == null) {
+    id = `c${seed}`
+    seed += 1
+    classIdMap.set(c, id)
+  }
+  return id
+}
+
+function cacheClass(c: Function) {
+  const win = window as any
+  const key = '__x6_class__'
+  let cache = win[key]
+  if (cache == null) {
+    cache = win[key] = {}
+  }
+
+  const id = getClassId(c)
+  if (cache[id] == null) {
+    cache[id] = c
+  }
+
+  return `window['${key}']['${id}']`
+}
+
+/**
+ * Extends class with specified class name.
+ */
+export function createClass<T>(className: string, base: Function): T {
+  const fn = cacheClass(base)
+  // tslint:disable-next-line
+  const cls = new Function(
+    `return function ${className}() { return ${fn}.apply(this, arguments) }`,
+  )()
+  inherit(cls, base)
+  return cls as T
+}

packages/x6/src/util/object/object.ts

@@ -12,22 +12,9 @@ export {
   extend,
 } from 'lodash'
 
-import { has, isPlainObject } from 'lodash'
+export * from './inherit'
 
-/**
- * @see https://www.typescriptlang.org/docs/handbook/mixins.html
- */
-export function applyMixins(derivedCtor: any, ...baseCtors: any[]) {
-  baseCtors.forEach(baseCtor => {
-    Object.getOwnPropertyNames(baseCtor.prototype).forEach(name => {
-      Object.defineProperty(
-        derivedCtor.prototype,
-        name,
-        Object.getOwnPropertyDescriptor(baseCtor.prototype, name)!,
-      )
-    })
-  })
-}
+import { has, isPlainObject } from 'lodash'
 
 export function ensure<T>(value: T | null | undefined, defaultValue: T) {
   return value != null ? value : defaultValue!