fix[once]: preserve this context

src/compat/function/once.spec.ts

@@ -30,4 +30,15 @@ describe('once', () => {
     expect(resultFunc).toThrow();
     expect(resultFunc).not.toThrow();
   });
+
+  it('should preserve this context', () => {
+    const object = {
+      value: 42,
+      getValue: once(function (this: { value: number }) {
+        return this.value;
+      }),
+    };
+
+    expect(object.getValue()).toBe(42);
+  });
 });

src/function/once.spec.ts

@@ -32,4 +32,15 @@ describe('once', () => {
     expect(onceFunc()).toBeUndefined();
     expect(func).toHaveBeenCalledTimes(1);
   });
+
+  it('should preserve this context', () => {
+    const object = {
+      value: 42,
+      getValue: once(function (this: { value: number }) {
+        return this.value;
+      }),
+    };
+
+    expect(object.getValue()).toBe(42);
+  });
 });

src/function/once.ts

@@ -12,7 +12,7 @@
  * initialize();
  * // => `createApplication` is invoked once
  */
 export function once<F extends (...args: any[]) => any>(func: F): F;
 
 /**
  * Creates a function that is restricted to invoking the provided function `func` once.
@@ -31,14 +31,14 @@
  * initialize(); // Logs: 'Initialized!' and returns true
  * initialize(); // Returns true without logging
  */
 export function once<F extends (() => any) | ((...args: any[]) => void)>(func: F): F {
   let called = false;
   let cache: ReturnType<F>;
 
-  return function (...args: Parameters<F>): ReturnType<F> {
+  return function (this: unknown, ...args: Parameters<F>): ReturnType<F> {
     if (!called) {
       called = true;
-      cache = func(...args);
+      cache = func.apply(this, args);
     }
 
     return cache;