Changes in sixel module to be compatible with oldstable.

- Reimplement abs_diff().
- Use positional arguments to format the error message in assert_color!().

1 files changed, 15 insertions, 4 deletions

diff --git a/alacritty_terminal/src/graphics/sixel.rs b/alacritty_terminal/src/graphics/sixel.rs
index acad29c8..b3953a93 100644
--- a/alacritty_terminal/src/graphics/sixel.rs
+++ b/alacritty_terminal/src/graphics/sixel.rs
@@ -643,16 +643,27 @@ mod tests {
         // We allow some difference between each component to ignore rounding
         // errors.
 
+        // Reimplement abs_diff to be compatible with rustc before 1.60.
+        fn abs_diff(x: u8, y: u8) -> u8 {
+            if x > y {
+                x - y
+            } else {
+                y - x
+            }
+        }
+
         macro_rules! assert_color {
             ($h:expr, $l:expr, $s:expr => $r:expr, $g:expr, $b:expr) => {
                 let left = hls_to_rgb($h, $l, $s);
                 let right = rgb($r, $g, $b, 255);
 
                 assert!(
-                    left.r.abs_diff(right.r) < 4
-                        && left.g.abs_diff(right.g) < 4
-                        && left.b.abs_diff(right.b) < 4,
-                    "Expected {right:?} Found {left:?}"
+                    abs_diff(left.r, right.r) < 4
+                        && abs_diff(left.g, right.g) < 4
+                        && abs_diff(left.b, right.b) < 4,
+                    "Expected {:?} Found {:?}",
+                    right,
+                    left,
                 );
             };
         }