additional handlers config

Author: nick-lvov-dev

index.ts

@@ -1,61 +1,61 @@
-export type TypedPathKey = string | symbol | number;
+function pathToString(path: string[]): string {
+    return path.reduce((current, next) => {
+        if (+next === +next) {
+            current += `[${next}]`;
+        } else {
+            current += current === '' ? `${next}` : `.${next}`;
+        }
 
-export type TypedPathNode<T> = {
-    $path: string;
-    $raw: TypedPathKey[];
-};
+        return current;
+    }, '');
+}
+
+export type TypedPathKey = string | symbol | number;
 
 export type TypedPathFunction<T> = (...args: any[]) => T;
 
-export type TypedPathWrapper<T> = (T extends Array<infer Z>
+export type TypedPathHandlersConfig = Record<string, <T extends TypedPathHandlersConfig = Record<never, never>>(path: string[], additionalHandlers?: T) => any>;
+
+const defaultHandlersConfig = {
+    $path: (path: string[]) => pathToString(path),
+    $raw: (path: string[]) => path,
+    toString: (path: string[]) => () => pathToString(path),
+    [Symbol.toStringTag]: (path: string[]) => () => pathToString(path),
+    valueOf: (path: string[]) => () => pathToString(path),
+}
+
+export type TypedPathHandlers<T extends TypedPathHandlersConfig> = {
+    [key in keyof T]: ReturnType<T[key]>;
+};
+
+export type TypedPathWrapper<T, TPH extends TypedPathHandlers<Record<never, never>>> = (T extends Array<infer Z>
     ? {
-        [index: number]: TypedPathWrapper<Z>;
+        [index: number]: TypedPathWrapper<Z, TPH>;
     }
     : T extends TypedPathFunction<infer RET>
         ? {
-            (): TypedPathWrapper<RET>;
+            (): TypedPathWrapper<RET, TPH>;
         } & {
-            [P in keyof RET]: TypedPathWrapper<RET[P]>;
+            [P in keyof RET]: TypedPathWrapper<RET[P], TPH>;
         }
         : {
-            [P in keyof T]: TypedPathWrapper<T[P]>;
+            [P in keyof T]: TypedPathWrapper<T[P], TPH>;
         }
-    ) & TypedPathNode<T>;
-
-const toStringMethods: (string | symbol | number)[] = [
-    'toString',
-    Symbol.toStringTag,
-    'valueOf'
-];
+    ) & TypedPathHandlers<TPH>;
 
-function pathToString(path: string[]): string {
-    return path.reduce((current, next) => {
-        if (+next === +next) {
-            current += `[${next}]`;
-        } else {
-            current += current === '' ? `${next}` : `.${next}`;
-        }
-
-        return current;
-    }, '');
-}
-
-export function typedPath<T>(path: string[] = []): TypedPathWrapper<T> {
-    return <TypedPathWrapper<T>>new Proxy({}, {
+export function typedPath<T, K extends TypedPathHandlersConfig = Record<never, never>>(path: string[] = [], additionalHandlers?: K): TypedPathWrapper<T, K & typeof defaultHandlersConfig> {
+    return <TypedPathWrapper<T, K & typeof defaultHandlersConfig>>new Proxy({}, {
         get(target: T, name: TypedPathKey) {
-            if (name === '$path') {
-                return pathToString(path);
-            }
-
-            if (name === '$raw') {
-                return path;
-            }
+            const handlersConfig: TypedPathHandlersConfig = { ...(additionalHandlers ?? {}), ...defaultHandlersConfig };
 
-            if (toStringMethods.includes(name)) {
-                return () => pathToString(path);
+            const keys: (keyof typeof handlersConfig)[] = Object.keys(handlersConfig);
+            for (const key of keys) {
+                if (key === name) {
+                    return handlersConfig[key](path, additionalHandlers);
+                }
             }
 
-            return typedPath([...path, name.toString()]);
+            return typedPath([...path, name.toString()], additionalHandlers);
         }
     });
 }