wip-update

Author: aditya520

target_chains/ethereum/contracts/forge-test/utils/PythTestUtils.t.sol

@@ -438,6 +438,11 @@ contract PythUtilsTest is Test, WormholeTestUtils, PythTestUtils, IPythEvents {
 
         // Price with 4 decimals and exponent 5
         assertEq(PythUtils.convertToUint(100, 1, 2), 100_000); // 100 with 3 zeros  
+
+
+        // Edge Cases
+        assertEq(PythUtils.convertToUint(100, -255, 18), 0);
+        // assertEq(PythUtils.convertToUint(100, 255, 18), 100_00_000_000_000_000_000_000_000);
     }
 
     function testCombinePrices() public {

target_chains/ethereum/sdk/solidity/Math.sol

@@ -174,4 +174,35 @@ library Math {
         }
     }
 
+    /**
+     * @dev Returns the multiplication of two unsigned integers, with a success flag (no overflow).
+     */
+    function tryMul(uint256 a, uint256 b) internal pure returns (bool success, uint256 result) {
+        unchecked {
+            uint256 c = a * b;
+             /// @solidity memory-safe-assembly
+            assembly {
+                // Only true when the multiplication doesn't overflow
+                // (c / a == b) || (a == 0)
+                success := or(eq(div(c, a), b), iszero(a))
+            }
+            // equivalent to: success ? c : 0
+            result = c * toUint(success);
+        }
+    }
+
+    /**
+     * @dev Returns the division of two unsigned integers, with a success flag (no division by zero).
+     */
+    function tryDiv(uint256 a, uint256 b) internal pure returns (bool success, uint256 result) {
+        unchecked {
+            success = b > 0;
+             /// @solidity memory-safe-assembly
+            assembly {
+                // The `DIV` opcode returns zero when the denominator is 0.
+                result := div(a, b)
+            }
+        }
+    }
+
 }

target_chains/ethereum/sdk/solidity/PythUtils.sol

@@ -29,12 +29,24 @@ library PythUtils {
             revert PythErrors.InvalidInputExpo();
         }
 
-        int256 combinedExpo = int32(int8(targetDecimals)) + int32(int8(uint8(uint32(expo))));
+        int256 combinedExpo = int32(int8(targetDecimals)) + expo;
+        console.log("combinedExpo", combinedExpo);
 
         if (combinedExpo > 0) {
-            return uint(uint64(price)) * 10 ** uint32(int32(combinedExpo));
+            (bool success, uint256 result) = Math.tryMul(uint64(price), 10 ** uint(uint32(int32(combinedExpo))));
+            if (!success) {
+                revert PythErrors.CombinedPriceOverflow();
+            }
+            return result;
         } else {
-            return uint(uint64(price)) / 10 ** uint32(Math.abs(combinedExpo));
+            console.log("combinedExpo < 0");
+            console.log("price", price);
+            console.log("Math.abs(combinedExpo)", Math.abs(combinedExpo));
+            (bool success, uint256 result) = Math.tryDiv(uint64(price), 10 ** uint(Math.abs(combinedExpo)));
+            if (!success) {
+                revert PythErrors.CombinedPriceOverflow();
+            }
+            return result;
         }
     }