Always wrap BigNumbers returned by web3 with our own version and add comment

2 files changed, 11 insertions, 5 deletions

diff --git a/src/contract_wrappers/exchange_wrapper.ts b/src/contract_wrappers/exchange_wrapper.ts
index 8b20d2b4d..2894c5a9f 100644
--- a/src/contract_wrappers/exchange_wrapper.ts
+++ b/src/contract_wrappers/exchange_wrapper.ts
@@ -70,7 +70,9 @@ export class ExchangeWrapper extends ContractWrapper {
         assert.isValidOrderHash('orderHashHex', orderHashHex);
 
         const exchangeContract = await this.getExchangeContractAsync();
-        const unavailableAmountInBaseUnits = await exchangeContract.getUnavailableValueT.call(orderHashHex);
+        let unavailableAmountInBaseUnits = await exchangeContract.getUnavailableValueT.call(orderHashHex);
+        // Wrap BigNumbers returned from web3 with our own (later) version of BigNumber
+        unavailableAmountInBaseUnits = new BigNumber(unavailableAmountInBaseUnits);
         return unavailableAmountInBaseUnits;
     }
     /**
@@ -80,7 +82,9 @@ export class ExchangeWrapper extends ContractWrapper {
         assert.isValidOrderHash('orderHashHex', orderHashHex);
 
         const exchangeContract = await this.getExchangeContractAsync();
-        const fillAmountInBaseUnits = await exchangeContract.filled.call(orderHashHex);
+        let fillAmountInBaseUnits = await exchangeContract.filled.call(orderHashHex);
+        // Wrap BigNumbers returned from web3 with our own (later) version of BigNumber
+        fillAmountInBaseUnits = new BigNumber(fillAmountInBaseUnits);
         return fillAmountInBaseUnits;
     }
     /**
@@ -90,7 +94,9 @@ export class ExchangeWrapper extends ContractWrapper {
         assert.isValidOrderHash('orderHashHex', orderHashHex);
 
         const exchangeContract = await this.getExchangeContractAsync();
-        const cancelledAmountInBaseUnits = await exchangeContract.cancelled.call(orderHashHex);
+        let cancelledAmountInBaseUnits = await exchangeContract.cancelled.call(orderHashHex);
+        // Wrap BigNumbers returned from web3 with our own (later) version of BigNumber
+        cancelledAmountInBaseUnits = new BigNumber(cancelledAmountInBaseUnits);
         return cancelledAmountInBaseUnits;
     }
     /**
diff --git a/src/contract_wrappers/token_wrapper.ts b/src/contract_wrappers/token_wrapper.ts
index cedbfbdae..69bcc9024 100644
--- a/src/contract_wrappers/token_wrapper.ts
+++ b/src/contract_wrappers/token_wrapper.ts
@@ -28,8 +28,7 @@ export class TokenWrapper extends ContractWrapper {
 
         const tokenContract = await this.getTokenContractAsync(tokenAddress);
         let balance = await tokenContract.balanceOf.call(ownerAddress);
-        // The BigNumber instance returned by Web3 is of a much older version then our own, we therefore
-        // should always re-instantiate the returned BigNumber after retrieval.
+        // Wrap BigNumbers returned from web3 with our own (later) version of BigNumber
         balance = new BigNumber(balance);
         return balance;
     }
@@ -44,6 +43,7 @@ export class TokenWrapper extends ContractWrapper {
         const tokenContract = await this.getTokenContractAsync(tokenAddress);
         const proxyAddress = await this.getProxyAddressAsync();
         let allowanceInBaseUnits = await tokenContract.allowance.call(ownerAddress, proxyAddress);
+        // Wrap BigNumbers returned from web3 with our own (later) version of BigNumber
         allowanceInBaseUnits = new BigNumber(allowanceInBaseUnits);
         return allowanceInBaseUnits;
     }