Number of segments in a string

#[test]
fn test_empty() {
    let start = std::time::Instant::now();
    let val = Solution::count_segments("".to_string());
    let expected = 0;
    log_result!(val == expected, "test_empty", start, &expected, &val);
    assert_eq!(val, expected);
}

#[test]
fn test_example_1() {
    let start = std::time::Instant::now();
    let val = Solution::count_segments("Hello, my name is John".to_string());
    let expected = 5;
    log_result!(val == expected, "test_example_1", start, &expected, &val);
    assert_eq!(val, expected);
}

#[test]
fn test_example_2() {
    let start = std::time::Instant::now();
    let val = Solution::count_segments("Hello".to_string());
    let expected = 1;
    log_result!(val == expected, "test_example_2", start, &expected, &val);
    assert_eq!(val, expected);
}

#[test]
fn test_leading_trailing_spaces() {
    let start = std::time::Instant::now();
    let val = Solution::count_segments("  hello  world  ".to_string());
    let expected = 2;
    log_result!(val == expected, "test_leading_trailing_spaces", start, &expected, &val);
    assert_eq!(val, expected);
}

#[test]
fn test_spaces_only() {
    let start = std::time::Instant::now();
    let val = Solution::count_segments("    ".to_string());
    let expected = 0;
    log_result!(val == expected, "test_spaces_only", start, &expected, &val);
    assert_eq!(val, expected);
}