fix bug in LibFractions reference function

contracts/exchange-libs/src/reference_functions.ts

@@ -129,7 +129,7 @@ export const LibFractions = {
     normalize: (
         numerator: BigNumber,
         denominator: BigNumber,
-        maxValue: BigNumber = new BigNumber(2 ** 127),
+        maxValue: BigNumber = new BigNumber(2).exponentiatedBy(127),
     ): [BigNumber, BigNumber] => {
         if (numerator.isGreaterThan(maxValue) || denominator.isGreaterThan(maxValue)) {
             let rescaleBase = numerator.isGreaterThanOrEqualTo(denominator) ? numerator : denominator;

contracts/integrations/test/framework/assertions/finalizePool.ts

@@ -179,13 +179,7 @@ export function validFinalizePoolAssertion(
                 beforeInfo.poolStats.membersStake,
             );
             [numerator, denominator] = ReferenceFunctions.LibFractions.normalize(numerator, denominator);
-            // There's a bug in our reference functions, probably due to the fact that safeDiv in
-            // Solidity truncates in bits, whereas the safeDiv reference function truncates in base 10.
-            assertRoughlyEquals(
-                mostRecentCumulativeRewards.numerator.dividedBy(mostRecentCumulativeRewards.denominator),
-                numerator.dividedBy(denominator),
-                PRECISION,
-            );
+            expect(mostRecentCumulativeRewards).to.deep.equal({ numerator, denominator });
 
             // Check that aggregated stats have been updated
             const aggregatedStats = AggregatedStats.fromArray(