public function testWithLibFunction() { $lib = function ($function, $parameter1, $parameter2) { switch ($function) { case '+': return $parameter1 + $parameter2; } return null; }; $function = function ($lib, $parameter1, $parameter2) { return $lib('+', $parameter1, $parameter2); }; $resultFunction = LJSON::withLib($lib, $function); $this->assertEquals(3, $resultFunction(1, 2)); $this->assertEquals(13, $resultFunction(5, 8)); $this->assertEquals(-12, $resultFunction(0, -12)); }