Split strings by separator

#[test]
fn t1() {
    let start = std::time::Instant::now();
    let val = Solution::split_words_by_separator(vec!["one.two.three".to_string(), "four.five".to_string(), "six".to_string()], '.');
    let expected = vec!["one".to_string(), "two".to_string(), "three".to_string(), "four".to_string(), "five".to_string(), "six".to_string()];
    log_result!(val == expected, "t1", start, &expected, &val);
    assert_eq!(val, expected);
}

#[test]
fn t2() {
    let start = std::time::Instant::now();
    let val = Solution::split_words_by_separator(vec!["$easy$".to_string(), "$problem$".to_string()], '$');
    let expected = vec!["easy".to_string(), "problem".to_string()];
    log_result!(val == expected, "t2", start, &expected, &val);
    assert_eq!(val, expected);
}

#[test]
fn t4() {
    let start = std::time::Instant::now();
    let val = Solution::split_words_by_separator(vec!["abc".to_string()], '.');
    let expected = vec!["abc".to_string()];
    log_result!(val == expected, "t4", start, &expected, &val);
    assert_eq!(val, expected);
}

#[test]
fn t5() {
    let start = std::time::Instant::now();
    let val = Solution::split_words_by_separator(vec![",a,b,".to_string()], ',');
    let expected = vec!["a".to_string(), "b".to_string()];
    log_result!(val == expected, "t5", start, &expected, &val);
    assert_eq!(val, expected);
}

#[test]
fn t6() {
    let start = std::time::Instant::now();
    let val = Solution::split_words_by_separator(vec!["a|b".to_string()], '|');
    let expected = vec!["a".to_string(), "b".to_string()];
    log_result!(val == expected, "t6", start, &expected, &val);
    assert_eq!(val, expected);
}