From 86f8a37930b5610d06929dc8cd22989ee6c96f7b Mon Sep 17 00:00:00 2001
From: Bruno Garcia <brunoely.gc@gmail.com>
Date: Wed, 11 Mar 2026 21:19:30 -0300
Subject: [PATCH] operators: when creating one mutant per line, prioritize
 hardest operators

---
 src/operators.rs | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/src/operators.rs b/src/operators.rs
index 090afb0..db7bbc1 100644
--- a/src/operators.rs
+++ b/src/operators.rs
@@ -32,14 +32,19 @@ pub fn get_regex_operators() -> Result<Vec<MutationOperator>, regex::Error> {
         ("true", "false"),
         ("false", "true"),
         (r" / ", " * "),
-        (r" > ", " < "),
+        // Boundary (off-by-one) mutations first — hardest to kill
+        (r" >= ", " > "),
+        (r" <= ", " < "),
         (r" > ", " >= "),
-        (r" > ", " <= "),
-        (r" < ", " > "),
         (r" < ", " <= "),
-        (r" < ", " >= "),
+        // Direction flips — easier to detect
         (r" >= ", " <= "),
-        (r" >= ", " > "),
+        (r" <= ", " >= "),
+        (r" > ", " < "),
+        (r" < ", " > "),
+        // Cross-boundary
+        (r" > ", " <= "),
+        (r" < ", " >= "),
         (r"&&", "||"),
         (r"\|\|", "&&"),
         (r" == ", " != "),