feat(api): added composite API

CHANGES.md

@@ -0,0 +1,5 @@
+# Changes Logs
+
+## v0.2.0
+
+- feat(api): added `composite` API.

docs/zh-CN/API.md

@@ -2,6 +2,22 @@
 
 ## API 篇
 
+### composite
+
+```ts
+function composite<
+    T extends IGeneralDecorator | IClassDecorator | IMethodParameterDecorator |
+              IMethodDecorator | IConstructorParameterDecorator | IStaticMethodDecorator |
+              IStaticMethodParameterDecorator | IPropertyDecorator | IStaticPropertyDecorator
+>(decorators: T[]): T;
+```
+
+这个方法用于将多个同类装饰器合成一个装饰器。
+
+> 多个装饰器，按数组排序顺序执行。
+
+参考示例：[00-ClassDecorator.ts](../../src/examples/00-ClassDecorator.ts)、[01-MemberMethodDecorator.ts](../../src/examples/01-MemberMethodDecorator.ts)。
+
 ### createAccessorDecorator
 
 ```ts

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@litert/decorator",
-  "version": "0.1.0",
+  "version": "0.2.0",
   "description": "The utility set of decorators.",
   "main": "./lib/index.js",
   "scripts": {

src/examples/00-ClassDecorator.ts

@@ -16,9 +16,34 @@
 
 import $Decorators from '../lib';
 
-@$Decorators.createClassDecorator((ctor) => console.log(`Decorated class ${ctor.name}`))
+
+@$Decorators.composite([
+    $Decorators.createClassDecorator((ctor) => console.log(`3. Class name before secord decorated: ${ctor.name}`)),
+    $Decorators.createClassDecorator((ctor) => (class Test2 extends ctor {
+
+        public name: string = 'Mick';
+
+        public printName(): void {
+
+            console.log(this.name);
+        }
+    })),
+    $Decorators.createClassDecorator((ctor) => console.log(`4. Class name after secord decorated: ${ctor.name}`)),
+    $Decorators.createClassDecorator((ctor) => console.log(Object.getOwnPropertyNames(ctor.prototype))),
+])
+@$Decorators.createClassDecorator((ctor) => console.log(`2. Class name after first decorated: ${ctor.name}`))
+@$Decorators.createClassDecorator((ctor) => (class Test1 extends ctor {
+
+    public age: number = 312;
+
+    public printAge(): void {
+
+        console.log(this.age);
+    }
+}))
+@$Decorators.createClassDecorator((ctor) => console.log(`1. Class name before decorated: ${ctor.name}`))
 class DemoClassDecorator {
 
 }
 
-new DemoClassDecorator();
+console.log(`Final class: ${DemoClassDecorator.name}`);

src/examples/01-MemberMethodDecorator.ts

@@ -18,10 +18,58 @@ import $Decorators from '../lib';
 
 class DemoMemberMethodDecorator {
 
-    @$Decorators.createMethodDecorator(function(proto, name) {
-        console.log(`Decorated method ${proto.constructor.name}::${name as string}`);
+    @$Decorators.createMethodDecorator(function(proto, name, dtr) {
+        console.log('test1: After decorated:')
+        console.log(`test1:   configurable: ${dtr.configurable}`);
+        console.log(`test1:   value: ${dtr.value}`);
     })
-    public test(): void {}
+    @$Decorators.createMethodDecorator(function(proto, name, dtr) {
+        console.log('test1: Before decorated:')
+        console.log(`test1:   configurable: ${dtr.configurable}`);
+        console.log(`test1:   value: ${dtr.value}`);
+
+        dtr.value = function hello() { console.log('this is test 1 hello'); };
+        dtr.configurable = false;
+    })
+    @$Decorators.createMethodDecorator(function(proto, name, dtr) {
+        console.log(`test1: Decorated method ${proto.constructor.name}::${name as string}`);
+    })
+    public test1(): void {
+
+        console.log('this is test 1');
+    }
+
+    @$Decorators.composite([
+
+        $Decorators.createMethodDecorator(function(proto, name, dtr) {
+            console.log(`test2: Decorated method ${proto.constructor.name}::${name as string}`);
+        }),
+        $Decorators.createMethodDecorator(function(proto, name, dtr) {
+            console.log('test2: Before decorated:')
+            console.log(`test2:   configurable: ${dtr.configurable}`);
+            console.log(`test2:   value: ${dtr.value}`);
+
+            dtr.value = function go() { console.log('this is test 2 go'); };
+            dtr.configurable = false;
+        }),
+        $Decorators.createMethodDecorator(function(proto, name, dtr) {
+            console.log('test2: After decorated:')
+            console.log(`test2:   configurable: ${dtr.configurable}`);
+            console.log(`test2:   value: ${dtr.value}`);
+        })
+    ])
+    public test2(): void {
+        console.log('this is test 2');
+    }
 }
 
-new DemoMemberMethodDecorator();
+console.log('test1: Final:')
+console.log(`test1:   configurable: ${Object.getOwnPropertyDescriptor(DemoMemberMethodDecorator.prototype, 'test1')!.configurable}`);
+console.log(`test1:   value: ${DemoMemberMethodDecorator.prototype.test1}`);
+
+console.log('test2: Final:')
+console.log(`test2:   configurable: ${Object.getOwnPropertyDescriptor(DemoMemberMethodDecorator.prototype, 'test2')!.configurable}`);
+console.log(`test2:   value: ${DemoMemberMethodDecorator.prototype.test2}`);
+
+new DemoMemberMethodDecorator().test1();
+new DemoMemberMethodDecorator().test2();

src/lib/Common.ts

@@ -175,8 +175,8 @@ export type IConstructorParameterDecoratorProcessor = (ctor: IClassCtor, index:
  * Signature of any decorator.
  */
 export interface IGeneralDecorator {
-    (target: IClassCtor): void;
-    (target: IObject, propertyKey: string | symbol, index?: any): void;
+    (target: IClassCtor): any;
+    (target: IObject, propertyKey: string | symbol, index?: any): any;
 }
 
 export interface IGeneralDecoratorProcessorSet {
@@ -530,4 +530,17 @@ export interface IDecoratorUtility {
      * @param name  The name of static member in class.
      */
     isStaticAccessor(ctor: IClassCtor, name: string | symbol): boolean;
+
+    /**
+     * Composite multiple same-type decorator into a one.
+     *
+     * > The decorators will be applied in order of the decorator array.
+     *
+     * @param decorators The decorators list.
+     */
+    composite<
+        T extends IGeneralDecorator | IClassDecorator | IMethodParameterDecorator |
+        IMethodDecorator | IConstructorParameterDecorator | IStaticMethodDecorator |
+        IStaticMethodParameterDecorator | IPropertyDecorator | IStaticPropertyDecorator
+    >(decorators: T[]): T;
 }

src/lib/DecoratorUtility.ts

@@ -687,4 +687,36 @@ export class DecoratorUtility implements C.IDecoratorUtility {
 
         this._hookNativeReflectMetadata = true;
     }
+
+    public composite(decorators: any[]): any {
+
+        return function(a: any, b: any, c: any): any {
+
+            for (const d of (decorators as Array<(...args: any[]) => any>)) {
+
+                if (typeof c === 'object') {
+
+                    c = d(a, b, c) ?? c;
+                }
+                else if (b === undefined && c === undefined) {
+
+                    a = d(a, b, c) ?? a;
+                }
+                else {
+
+                    d(a, b, c);
+                }
+            }
+
+            if (typeof c === 'object') {
+
+                return c;
+            }
+            else if (b === undefined && c === undefined) {
+
+                return a;
+            }
+
+        } as any;
+    }
 }