You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: ffi_util.rs
    path of file: ./repos/rust-rocksdb/src
    
    the code of the file until where you have to start completion: // Copyright 2016 Alex Regueiro
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file
    
fn test_c_str_like_into() {
    fn test<S: CStrLike>(value: S) -> Result<CString, S::Error> {
        value.into_c_string()
    }

    let want = CString::new("foo").unwrap();

    assert_eq!(Ok(want.clone()), test("foo")); // &str
    assert_eq!(Ok(want.clone()), test(&String::from("foo"))); // &String
    assert_eq!(
        Ok(want.clone()),
        test(CString::new("foo").unwrap().as_ref())
    ); // &CStr
    assert_eq!(Ok(want.clone()), test(&CString::new("foo").unwrap())); // &CString
    assert_eq!(Ok(want), test(CString::new("foo").unwrap())); // CString

    assert_eq!(3, test("foo\0bar").err().unwrap().nul_position());
}