Make a square with the same color

#[test]
fn t1() {
    let start = std::time::Instant::now();
    // Example 1: change [0][2] to B -> top-right 2x2 = [W,B] [W,W] still not same...
    // Actually can_make_square should return true
    let val = Solution::can_make_square(g(&["BWB","BWW","BWB"]));
    let expected = true;
    log_result!(val == expected, "t1", start, &expected, &val);
    assert!(val);
}

#[test]
fn t2() {
    let start = std::time::Instant::now();
    // Example 2: checkerboard pattern
    let val = Solution::can_make_square(g(&["BWB","WBW","BWB"]));
    let expected = false;
    log_result!(val == expected, "t2", start, &expected, &val);
    assert!(!val);
}

#[test]
fn t3() {
    let start = std::time::Instant::now();
    // Example 3: already has 2x2 same color
    let val = Solution::can_make_square(g(&["BWB","BWW","BWW"]));
    let expected = true;
    log_result!(val == expected, "t3", start, &expected, &val);
    assert!(val);
}

#[test]
fn t4() {
    let start = std::time::Instant::now();
    // All B: top-left 2x2 has 4 B -> true
    let val = Solution::can_make_square(g(&["BBB","BBB","BBB"]));
    let expected = true;
    log_result!(val == expected, "t4", start, &expected, &val);
    assert!(val);
}

#[test]
fn t5() {
    let start = std::time::Instant::now();
    // All W
    let val = Solution::can_make_square(g(&["WWW","WWW","WWW"]));
    let expected = true;
    log_result!(val == expected, "t5", start, &expected, &val);
    assert!(val);
}

#[test]
fn t6() {
    let start = std::time::Instant::now();
    // 3 B in top-left -> can make 2x2
    let val = Solution::can_make_square(g(&["BBW","BBW","WWW"]));
    let expected = true;
    log_result!(val == expected, "t6", start, &expected, &val);
    assert!(val);
}

#[test]
fn t7() {
    // 2B 2W in each 2x2 -> can't fix with 1 change -> false
    assert!(!Solution::can_make_square(g(&["BWB","WBW","BWB"])));
}