independant fuzz tests of and without pos

Author: Amxx

test/utils/Bytes.t.sol

@@ -11,7 +11,20 @@ contract BytesTest is Test {
 
     // INDEX OF
     function testIndexOf(bytes memory buffer, bytes1 s) public pure {
-        testIndexOf(buffer, s, 0);
+        uint256 result = Bytes.indexOf(buffer, s);
+
+        if (buffer.length == 0) {
+            // Case 0: buffer is empty
+            assertEq(result, type(uint256).max);
+        } else if (result == type(uint256).max) {
+            // Case 1: search value could not be found
+            for (uint256 i = 0; i < buffer.length; ++i) assertNotEq(buffer[i], s);
+        } else {
+            // Case 2: search value was found
+            assertEq(buffer[result], s);
+            // search value is not present anywhere before the found location
+            for (uint256 i = 0; i < result; ++i) assertNotEq(buffer[i], s);
+        }
     }
 
     function testIndexOf(bytes memory buffer, bytes1 s, uint256 pos) public pure {
@@ -32,7 +45,20 @@ contract BytesTest is Test {
     }
 
     function testLastIndexOf(bytes memory buffer, bytes1 s) public pure {
-        testLastIndexOf(buffer, s, 0);
+        uint256 result = Bytes.lastIndexOf(buffer, s);
+
+        if (buffer.length == 0) {
+            // Case 0: buffer is empty
+            assertEq(result, type(uint256).max);
+        } else if (result == type(uint256).max) {
+            // Case 1: search value could not be found
+            for (uint256 i = 0; i < buffer.length; ++i) assertNotEq(buffer[i], s);
+        } else {
+            // Case 2: search value was found
+            assertEq(buffer[result], s);
+            // search value is not present anywhere after the found location
+            for (uint256 i = result + 1; i < buffer.length; ++i) assertNotEq(buffer[i], s);
+        }
     }
 
     function testLastIndexOf(bytes memory buffer, bytes1 s, uint256 pos) public pure {