more fuzzing

test/utils/math/Math.t.sol

@@ -56,7 +56,7 @@ contract MathTest is Test {
     }
 
     // INV
-    function testInv(uint256 seed) public {
+    function testInv1(uint256 seed) public {
         uint256 p;
         uint256 value;
         uint256 inverse;
@@ -80,6 +80,13 @@ contract MathTest is Test {
         assertEq(mulmod(value, inverse, p), 1);
     }
 
+    function testInv2(uint256 value, uint256 p) public {
+        uint256 inverse = Math.inv(value, p);
+        if (inverse != 0) {
+            assertEq(mulmod(value, inverse, p), 1);
+        }
+    }
+
     // LOG2
     function testLog2(uint256 input, uint8 r) public {
         Math.Rounding rounding = _asRounding(r);