#33

packages/monster/source/data/transformer.js

@@ -6,7 +6,8 @@
 
 import {Monster} from '../namespace.js';
 import {Base} from '../types/base.js';
-import {validateString, validatePrimitive, validateFunction, validateInteger} from '../types/validate.js';
+import {getGlobal} from "../types/global.js";
+import {validateString, validatePrimitive, validateFunction, validateInteger, validateObject} from '../types/validate.js';
 import {isObject, isString, isArray} from '../types/is.js';
 import {ID} from '../types/id.js';
 import {clone} from "../util/clone.js";
@@ -138,14 +139,24 @@ class Transformer extends Base {
      *
      * @param {string} name
      * @param {function} callback
+     * @param {object} context
      * @returns {Transformer}
      * @throws {TypeError} value is not a string
      * @throws {TypeError} value is not a function
      */
-    setCallback(name, callback) {
+    setCallback(name, callback, context) {
         validateString(name)
         validateFunction(callback)
-        this.callbacks.set(name, callback);
+        
+        if(context!==undefined) {
+            validateObject(context);
+        }
+        
+        this.callbacks.set(name, {
+            callback: callback,
+            context: context,
+        });
+        
         return this;
     }
 
@@ -297,18 +308,21 @@ function transform(value) {
 
             let callback;
             let callbackName = args.shift();
+            let context = getGlobal();
 
             if (isObject(value) && value.hasOwnProperty(callbackName)) {
                 callback = value[callbackName];
             } else if (this.callbacks.has(callbackName)) {
-                callback = this.callbacks.get(callbackName);
+                let s = this.callbacks.get(callbackName);
+                callback = s?.['callback'];
+                context = s?.['context'];
             } else if (typeof window === 'object' && window.hasOwnProperty(callbackName)) {
                 callback = window[callbackName];
             }
             validateFunction(callback);
 
             args.unshift(value);
-            return callback(...args);
+            return callback.call(context, ...args);
 
         case  'plain':
         case  'plaintext':