How do I pass a variable to a function that then changes the variable depending on an if statement?

Question

I do not understand how to properly set up this line of logic without my variables going out of scope. I am trying to create the below function chunk_file. My first if statement ensures that the passed file does exist and that it is to be chunked by more than 0 bytes. The second if statement is checking that the file was passed from the directory I want all files to originate from and if it doesn't then I want it to change the Path and move the file to the correct directory. The issue is that no matter where I place the temp variable it's lifetime is dropped and cannot be borrowed but I see no other way to redefine src_path with the new path.

let test = Path::new(r"C:\\temp\\files\\test.txt");

fn main () {
    chunk_file(src_path: test, constant::CHUNK_SIZE_8MB);

}

fn chunk_file(mut src_path: &Path, chunk_size: u32) -> bool {
    let result = false;
    let file_directory: &Path = constant::FILE_DIRECTORY.as_ref();

    if src_path.exists() && chunk_size > 0 {
        if src_path.parent().unwrap() != file_directory {
            let mut temp: String = String::from("");
            temp.push_str(string: file_directory.to_str().unwrap());
            temp.push_str(string: src_path.file_name().unwrap().to_str().unwrap());
            match fs::rename(from: src_path, to: &temp) {
                Ok(_) => {}
                Err(e: Error) => println!("Error in file rename => {:?}", e) 
            }
            src_path = Path::new(&temp) 
        }
        else {
            src_path = src_path
        }
    }

result
}

I have placed temp inside the innermost if statement, inside the outermost if statement, in the main function, outside of the main function and I either get a temp gets dropped error or that I need to make the function a variable [ let chunk_file = || { \code } ] which is not at all what I need as it needs to be a function. I have tried dereferencing and get the error you cannot dereference a &mut variable. I have tried making a [ let src_check = if \logic { \code } variable and then doing src_path = Path::new(&src_check) ] and this still returns a &src_check is dropped while still borrowed.