Function withMock

withMock<TArgs extends unknown[], TReturn>(
fn: (...args: TArgs) => TReturn,
mockFn: (...args: TArgs) => TReturn,
): (...args: TArgs) => TReturn & { mocked: (...args: TArgs) => TReturn }
Wraps a function and attaches a mock version. The returned function calls the original, and .mocked() calls the mock.
Type Parameters
- TArgs extends unknown[]
  Argument types of the function.
- TReturn
  Return type of the function.
Parameters
- fn: (...args: TArgs) => TReturn
  Original function.
- mockFn: (...args: TArgs) => TReturn
  Mock implementation.
Returns (...args: TArgs) => TReturn & { mocked: (...args: TArgs) => TReturn }
Function with attached .mocked() method.
Example
```
const realFn = (x: number) => x * 2;
const mockFn = (x: number) => 42;
const wrapped = withMock(realFn, mockFn);

wrapped(3); // 6
wrapped.mocked(3); // 42
```
Source
```
export function withMock<TArgs extends unknown[], TReturn>(
  fn: (...args: TArgs) => TReturn,
  mockFn: (...args: TArgs) => TReturn
): ((...args: TArgs) => TReturn) & { mocked: (...args: TArgs) => TReturn } {
  return Object.assign(fn, { mocked: mockFn });
}
```