Fix scoreboard division overflow for minimum integer

Co-Authored-By: Codex gpt-6-astra <[email protected]>

crates/horizon-client/src/scoreboard_cmd.rs

@@ -776,7 +776,7 @@ fn players(id: &str, ctx: &Context, env: &mut dyn Env) -> CmdResult<i32> {
     }
 }
 
-/// `OperationArgument`: the new (target, source) values.
+/// `OperationArgument.getSimpleOperation`: the new (target, source) values.
 pub fn apply_operation(op: &str, a: i32, b: i32) -> CmdResult<(i32, i32)> {
     let div0 = || err("arguments.operation.div0", &[]);
     Ok(match op {
@@ -789,7 +789,7 @@ pub fn apply_operation(op: &str, a: i32, b: i32) -> CmdResult<(i32, i32)> {
                 return Err(div0());
             }
             (
-                a.wrapping_div(b) - i32::from((a % b != 0) && ((a < 0) != (b < 0))),
+                a.wrapping_div(b) - i32::from((a.wrapping_rem(b) != 0) && ((a < 0) != (b < 0))),
                 b,
             )
         }

crates/horizon-client/src/scoreboard_cmd_tests.rs

@@ -189,6 +189,27 @@ fn operations_use_floor_semantics() {
     assert_eq!(apply_operation("*=", i32::MAX, 2).unwrap().0, -2);
 }
 
+#[test]
+fn division_wraps_minimum_integer_by_negative_one() {
+    let mut m = mock();
+    run(&mut m, "scoreboard objectives add poc dummy").unwrap();
+    run(&mut m, "scoreboard players set target poc -2147483648").unwrap();
+    run(&mut m, "scoreboard players set divisor poc -1").unwrap();
+    run(
+        &mut m,
+        "scoreboard players operation target poc /= divisor poc",
+    )
+    .unwrap();
+    assert_eq!(
+        run(&mut m, "scoreboard players get target poc").unwrap(),
+        i32::MIN
+    );
+    assert_eq!(
+        run(&mut m, "scoreboard players get divisor poc").unwrap(),
+        -1
+    );
+}
+
 #[test]
 fn triggers() {
     let mut m = mock();