Introduce SignedOrder class and remove type assertions

9 files changed, 365 insertions, 324 deletions

diff --git a/packages/contracts/test/exchange/core.ts b/packages/contracts/test/exchange/core.ts
index 7a654b2df..4c3c1dd93 100644
--- a/packages/contracts/test/exchange/core.ts
+++ b/packages/contracts/test/exchange/core.ts
@@ -22,6 +22,7 @@ import { crypto } from '../../util/crypto';
 import { ExchangeWrapper } from '../../util/exchange_wrapper';
 import { Order } from '../../util/order';
 import { OrderFactory } from '../../util/order_factory';
+import { SignedOrder } from '../../util/signed_order';
 import { BalancesByOwner, ContractName, ExchangeContractErrs } from '../../util/types';
 import { chaiSetup } from '../utils/chai_setup';
 import { deployer } from '../utils/deployer';
@@ -46,7 +47,7 @@ describe('Exchange', () => {
     let exchange: ExchangeContract;
     let tokenTransferProxy: TokenTransferProxyContract;
 
-    let order: Order;
+    let signedOrder: SignedOrder;
     let balances: BalancesByOwner;
     let exWrapper: ExchangeWrapper;
     let dmyBalances: Balances;
@@ -147,85 +148,85 @@ describe('Exchange', () => {
     describe('fillOrder', () => {
         beforeEach(async () => {
             balances = await dmyBalances.getAsync();
-            order = await orderFactory.newSignedOrderAsync();
+            signedOrder = await orderFactory.newSignedOrderAsync();
         });
 
         it('should create an unfillable order', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 makerTokenAmount: new BigNumber(1001),
                 takerTokenAmount: new BigNumber(3),
             });
 
             const filledTakerTokenAmountBefore = await zeroEx.exchange.getFilledTakerAmountAsync(
-                order.getOrderHashHex(),
+                signedOrder.getOrderHashHex(),
             );
             expect(filledTakerTokenAmountBefore).to.be.bignumber.equal(0);
 
             const fillTakerTokenAmount1 = new BigNumber(2);
-            await exWrapper.fillOrderAsync(order, taker, {
+            await exWrapper.fillOrderAsync(signedOrder, taker, {
                 fillTakerTokenAmount: fillTakerTokenAmount1,
             });
 
             const filledTakerTokenAmountAfter1 = await zeroEx.exchange.getFilledTakerAmountAsync(
-                order.getOrderHashHex(),
+                signedOrder.getOrderHashHex(),
             );
             expect(filledTakerTokenAmountAfter1).to.be.bignumber.equal(fillTakerTokenAmount1);
 
             const fillTakerTokenAmount2 = new BigNumber(1);
-            await exWrapper.fillOrderAsync(order, taker, {
+            await exWrapper.fillOrderAsync(signedOrder, taker, {
                 fillTakerTokenAmount: fillTakerTokenAmount2,
             });
 
             const filledTakerTokenAmountAfter2 = await zeroEx.exchange.getFilledTakerAmountAsync(
-                order.getOrderHashHex(),
+                signedOrder.getOrderHashHex(),
             );
             expect(filledTakerTokenAmountAfter2).to.be.bignumber.equal(filledTakerTokenAmountAfter1);
         });
 
         it('should transfer the correct amounts when makerTokenAmount === takerTokenAmount', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 makerTokenAmount: ZeroEx.toBaseUnitAmount(new BigNumber(100), 18),
                 takerTokenAmount: ZeroEx.toBaseUnitAmount(new BigNumber(100), 18),
             });
 
             const filledTakerTokenAmountBefore = await zeroEx.exchange.getFilledTakerAmountAsync(
-                order.getOrderHashHex(),
+                signedOrder.getOrderHashHex(),
             );
             expect(filledTakerTokenAmountBefore).to.be.bignumber.equal(0);
 
-            const fillTakerTokenAmount = order.params.takerTokenAmount.div(2);
-            await exWrapper.fillOrderAsync(order, taker, { fillTakerTokenAmount });
+            const fillTakerTokenAmount = signedOrder.params.takerTokenAmount.div(2);
+            await exWrapper.fillOrderAsync(signedOrder, taker, { fillTakerTokenAmount });
 
             const filledTakerTokenAmountAfter = await zeroEx.exchange.getFilledTakerAmountAsync(
-                order.getOrderHashHex(),
+                signedOrder.getOrderHashHex(),
             );
             expect(filledTakerTokenAmountAfter).to.be.bignumber.equal(fillTakerTokenAmount);
 
             const newBalances = await dmyBalances.getAsync();
 
             const fillMakerTokenAmount = fillTakerTokenAmount
-                .times(order.params.makerTokenAmount)
-                .dividedToIntegerBy(order.params.takerTokenAmount);
-            const paidMakerFee = order.params.makerFee
+                .times(signedOrder.params.makerTokenAmount)
+                .dividedToIntegerBy(signedOrder.params.takerTokenAmount);
+            const paidMakerFee = signedOrder.params.makerFee
                 .times(fillMakerTokenAmount)
-                .dividedToIntegerBy(order.params.makerTokenAmount);
-            const paidTakerFee = order.params.takerFee
+                .dividedToIntegerBy(signedOrder.params.makerTokenAmount);
+            const paidTakerFee = signedOrder.params.takerFee
                 .times(fillMakerTokenAmount)
-                .dividedToIntegerBy(order.params.makerTokenAmount);
-            expect(newBalances[maker][order.params.makerToken]).to.be.bignumber.equal(
-                balances[maker][order.params.makerToken].minus(fillMakerTokenAmount),
+                .dividedToIntegerBy(signedOrder.params.makerTokenAmount);
+            expect(newBalances[maker][signedOrder.params.makerToken]).to.be.bignumber.equal(
+                balances[maker][signedOrder.params.makerToken].minus(fillMakerTokenAmount),
             );
-            expect(newBalances[maker][order.params.takerToken]).to.be.bignumber.equal(
-                balances[maker][order.params.takerToken].add(fillTakerTokenAmount),
+            expect(newBalances[maker][signedOrder.params.takerToken]).to.be.bignumber.equal(
+                balances[maker][signedOrder.params.takerToken].add(fillTakerTokenAmount),
             );
             expect(newBalances[maker][zrx.address]).to.be.bignumber.equal(
                 balances[maker][zrx.address].minus(paidMakerFee),
             );
-            expect(newBalances[taker][order.params.takerToken]).to.be.bignumber.equal(
-                balances[taker][order.params.takerToken].minus(fillTakerTokenAmount),
+            expect(newBalances[taker][signedOrder.params.takerToken]).to.be.bignumber.equal(
+                balances[taker][signedOrder.params.takerToken].minus(fillTakerTokenAmount),
             );
-            expect(newBalances[taker][order.params.makerToken]).to.be.bignumber.equal(
-                balances[taker][order.params.makerToken].add(fillMakerTokenAmount),
+            expect(newBalances[taker][signedOrder.params.makerToken]).to.be.bignumber.equal(
+                balances[taker][signedOrder.params.makerToken].add(fillMakerTokenAmount),
             );
             expect(newBalances[taker][zrx.address]).to.be.bignumber.equal(
                 balances[taker][zrx.address].minus(paidTakerFee),
@@ -236,49 +237,49 @@ describe('Exchange', () => {
         });
 
         it('should transfer the correct amounts when makerTokenAmount > takerTokenAmount', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 makerTokenAmount: ZeroEx.toBaseUnitAmount(new BigNumber(200), 18),
                 takerTokenAmount: ZeroEx.toBaseUnitAmount(new BigNumber(100), 18),
             });
 
             const filledTakerTokenAmountBefore = await zeroEx.exchange.getFilledTakerAmountAsync(
-                order.getOrderHashHex(),
+                signedOrder.getOrderHashHex(),
             );
             expect(filledTakerTokenAmountBefore).to.be.bignumber.equal(0);
 
-            const fillTakerTokenAmount = order.params.takerTokenAmount.div(2);
-            await exWrapper.fillOrderAsync(order, taker, { fillTakerTokenAmount });
+            const fillTakerTokenAmount = signedOrder.params.takerTokenAmount.div(2);
+            await exWrapper.fillOrderAsync(signedOrder, taker, { fillTakerTokenAmount });
 
             const filledTakerTokenAmountAfter = await zeroEx.exchange.getFilledTakerAmountAsync(
-                order.getOrderHashHex(),
+                signedOrder.getOrderHashHex(),
             );
             expect(filledTakerTokenAmountAfter).to.be.bignumber.equal(fillTakerTokenAmount);
 
             const newBalances = await dmyBalances.getAsync();
 
             const fillMakerTokenAmount = fillTakerTokenAmount
-                .times(order.params.makerTokenAmount)
-                .dividedToIntegerBy(order.params.takerTokenAmount);
-            const paidMakerFee = order.params.makerFee
+                .times(signedOrder.params.makerTokenAmount)
+                .dividedToIntegerBy(signedOrder.params.takerTokenAmount);
+            const paidMakerFee = signedOrder.params.makerFee
                 .times(fillMakerTokenAmount)
-                .dividedToIntegerBy(order.params.makerTokenAmount);
-            const paidTakerFee = order.params.takerFee
+                .dividedToIntegerBy(signedOrder.params.makerTokenAmount);
+            const paidTakerFee = signedOrder.params.takerFee
                 .times(fillMakerTokenAmount)
-                .dividedToIntegerBy(order.params.makerTokenAmount);
-            expect(newBalances[maker][order.params.makerToken]).to.be.bignumber.equal(
-                balances[maker][order.params.makerToken].minus(fillMakerTokenAmount),
+                .dividedToIntegerBy(signedOrder.params.makerTokenAmount);
+            expect(newBalances[maker][signedOrder.params.makerToken]).to.be.bignumber.equal(
+                balances[maker][signedOrder.params.makerToken].minus(fillMakerTokenAmount),
             );
-            expect(newBalances[maker][order.params.takerToken]).to.be.bignumber.equal(
-                balances[maker][order.params.takerToken].add(fillTakerTokenAmount),
+            expect(newBalances[maker][signedOrder.params.takerToken]).to.be.bignumber.equal(
+                balances[maker][signedOrder.params.takerToken].add(fillTakerTokenAmount),
             );
             expect(newBalances[maker][zrx.address]).to.be.bignumber.equal(
                 balances[maker][zrx.address].minus(paidMakerFee),
             );
-            expect(newBalances[taker][order.params.takerToken]).to.be.bignumber.equal(
-                balances[taker][order.params.takerToken].minus(fillTakerTokenAmount),
+            expect(newBalances[taker][signedOrder.params.takerToken]).to.be.bignumber.equal(
+                balances[taker][signedOrder.params.takerToken].minus(fillTakerTokenAmount),
             );
-            expect(newBalances[taker][order.params.makerToken]).to.be.bignumber.equal(
-                balances[taker][order.params.makerToken].add(fillMakerTokenAmount),
+            expect(newBalances[taker][signedOrder.params.makerToken]).to.be.bignumber.equal(
+                balances[taker][signedOrder.params.makerToken].add(fillMakerTokenAmount),
             );
             expect(newBalances[taker][zrx.address]).to.be.bignumber.equal(
                 balances[taker][zrx.address].minus(paidTakerFee),
@@ -289,49 +290,49 @@ describe('Exchange', () => {
         });
 
         it('should transfer the correct amounts when makerTokenAmount < takerTokenAmount', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 makerTokenAmount: ZeroEx.toBaseUnitAmount(new BigNumber(100), 18),
                 takerTokenAmount: ZeroEx.toBaseUnitAmount(new BigNumber(200), 18),
             });
 
             const filledTakerTokenAmountBefore = await zeroEx.exchange.getFilledTakerAmountAsync(
-                order.getOrderHashHex(),
+                signedOrder.getOrderHashHex(),
             );
             expect(filledTakerTokenAmountBefore).to.be.bignumber.equal(0);
 
-            const fillTakerTokenAmount = order.params.takerTokenAmount.div(2);
-            await exWrapper.fillOrderAsync(order, taker, { fillTakerTokenAmount });
+            const fillTakerTokenAmount = signedOrder.params.takerTokenAmount.div(2);
+            await exWrapper.fillOrderAsync(signedOrder, taker, { fillTakerTokenAmount });
 
             const filledTakerTokenAmountAfter = await zeroEx.exchange.getFilledTakerAmountAsync(
-                order.getOrderHashHex(),
+                signedOrder.getOrderHashHex(),
             );
             expect(filledTakerTokenAmountAfter).to.be.bignumber.equal(fillTakerTokenAmount);
 
             const newBalances = await dmyBalances.getAsync();
 
             const fillMakerTokenAmount = fillTakerTokenAmount
-                .times(order.params.makerTokenAmount)
-                .dividedToIntegerBy(order.params.takerTokenAmount);
-            const paidMakerFee = order.params.makerFee
+                .times(signedOrder.params.makerTokenAmount)
+                .dividedToIntegerBy(signedOrder.params.takerTokenAmount);
+            const paidMakerFee = signedOrder.params.makerFee
                 .times(fillMakerTokenAmount)
-                .dividedToIntegerBy(order.params.makerTokenAmount);
-            const paidTakerFee = order.params.takerFee
+                .dividedToIntegerBy(signedOrder.params.makerTokenAmount);
+            const paidTakerFee = signedOrder.params.takerFee
                 .times(fillMakerTokenAmount)
-                .dividedToIntegerBy(order.params.makerTokenAmount);
-            expect(newBalances[maker][order.params.makerToken]).to.be.bignumber.equal(
-                balances[maker][order.params.makerToken].minus(fillMakerTokenAmount),
+                .dividedToIntegerBy(signedOrder.params.makerTokenAmount);
+            expect(newBalances[maker][signedOrder.params.makerToken]).to.be.bignumber.equal(
+                balances[maker][signedOrder.params.makerToken].minus(fillMakerTokenAmount),
             );
-            expect(newBalances[maker][order.params.takerToken]).to.be.bignumber.equal(
-                balances[maker][order.params.takerToken].add(fillTakerTokenAmount),
+            expect(newBalances[maker][signedOrder.params.takerToken]).to.be.bignumber.equal(
+                balances[maker][signedOrder.params.takerToken].add(fillTakerTokenAmount),
             );
             expect(newBalances[maker][zrx.address]).to.be.bignumber.equal(
                 balances[maker][zrx.address].minus(paidMakerFee),
             );
-            expect(newBalances[taker][order.params.takerToken]).to.be.bignumber.equal(
-                balances[taker][order.params.takerToken].minus(fillTakerTokenAmount),
+            expect(newBalances[taker][signedOrder.params.takerToken]).to.be.bignumber.equal(
+                balances[taker][signedOrder.params.takerToken].minus(fillTakerTokenAmount),
             );
-            expect(newBalances[taker][order.params.makerToken]).to.be.bignumber.equal(
-                balances[taker][order.params.makerToken].add(fillMakerTokenAmount),
+            expect(newBalances[taker][signedOrder.params.makerToken]).to.be.bignumber.equal(
+                balances[taker][signedOrder.params.makerToken].add(fillMakerTokenAmount),
             );
             expect(newBalances[taker][zrx.address]).to.be.bignumber.equal(
                 balances[taker][zrx.address].minus(paidTakerFee),
@@ -342,22 +343,22 @@ describe('Exchange', () => {
         });
 
         it('should transfer the correct amounts when taker is specified and order is claimed by taker', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 taker,
                 makerTokenAmount: ZeroEx.toBaseUnitAmount(new BigNumber(100), 18),
                 takerTokenAmount: ZeroEx.toBaseUnitAmount(new BigNumber(200), 18),
             });
 
             const filledTakerTokenAmountBefore = await zeroEx.exchange.getFilledTakerAmountAsync(
-                order.getOrderHashHex(),
+                signedOrder.getOrderHashHex(),
             );
             expect(filledTakerTokenAmountBefore).to.be.bignumber.equal(0);
 
-            const fillTakerTokenAmount = order.params.takerTokenAmount.div(2);
-            await exWrapper.fillOrderAsync(order, taker, { fillTakerTokenAmount });
+            const fillTakerTokenAmount = signedOrder.params.takerTokenAmount.div(2);
+            await exWrapper.fillOrderAsync(signedOrder, taker, { fillTakerTokenAmount });
 
             const filledTakerTokenAmountAfter = await zeroEx.exchange.getFilledTakerAmountAsync(
-                order.getOrderHashHex(),
+                signedOrder.getOrderHashHex(),
             );
             const expectedFillAmountTAfter = fillTakerTokenAmount.add(filledTakerTokenAmountBefore);
             expect(filledTakerTokenAmountAfter).to.be.bignumber.equal(expectedFillAmountTAfter);
@@ -365,28 +366,28 @@ describe('Exchange', () => {
             const newBalances = await dmyBalances.getAsync();
 
             const fillMakerTokenAmount = fillTakerTokenAmount
-                .times(order.params.makerTokenAmount)
-                .dividedToIntegerBy(order.params.takerTokenAmount);
-            const paidMakerFee = order.params.makerFee
+                .times(signedOrder.params.makerTokenAmount)
+                .dividedToIntegerBy(signedOrder.params.takerTokenAmount);
+            const paidMakerFee = signedOrder.params.makerFee
                 .times(fillMakerTokenAmount)
-                .dividedToIntegerBy(order.params.makerTokenAmount);
-            const paidTakerFee = order.params.takerFee
+                .dividedToIntegerBy(signedOrder.params.makerTokenAmount);
+            const paidTakerFee = signedOrder.params.takerFee
                 .times(fillMakerTokenAmount)
-                .dividedToIntegerBy(order.params.makerTokenAmount);
-            expect(newBalances[maker][order.params.makerToken]).to.be.bignumber.equal(
-                balances[maker][order.params.makerToken].minus(fillMakerTokenAmount),
+                .dividedToIntegerBy(signedOrder.params.makerTokenAmount);
+            expect(newBalances[maker][signedOrder.params.makerToken]).to.be.bignumber.equal(
+                balances[maker][signedOrder.params.makerToken].minus(fillMakerTokenAmount),
             );
-            expect(newBalances[maker][order.params.takerToken]).to.be.bignumber.equal(
-                balances[maker][order.params.takerToken].add(fillTakerTokenAmount),
+            expect(newBalances[maker][signedOrder.params.takerToken]).to.be.bignumber.equal(
+                balances[maker][signedOrder.params.takerToken].add(fillTakerTokenAmount),
             );
             expect(newBalances[maker][zrx.address]).to.be.bignumber.equal(
                 balances[maker][zrx.address].minus(paidMakerFee),
             );
-            expect(newBalances[taker][order.params.takerToken]).to.be.bignumber.equal(
-                balances[taker][order.params.takerToken].minus(fillTakerTokenAmount),
+            expect(newBalances[taker][signedOrder.params.takerToken]).to.be.bignumber.equal(
+                balances[taker][signedOrder.params.takerToken].minus(fillTakerTokenAmount),
             );
-            expect(newBalances[taker][order.params.makerToken]).to.be.bignumber.equal(
-                balances[taker][order.params.makerToken].add(fillMakerTokenAmount),
+            expect(newBalances[taker][signedOrder.params.makerToken]).to.be.bignumber.equal(
+                balances[taker][signedOrder.params.makerToken].add(fillMakerTokenAmount),
             );
             expect(newBalances[taker][zrx.address]).to.be.bignumber.equal(
                 balances[taker][zrx.address].minus(paidTakerFee),
@@ -397,141 +398,141 @@ describe('Exchange', () => {
         });
 
         it('should fill remaining value if fillTakerTokenAmount > remaining takerTokenAmount', async () => {
-            const fillTakerTokenAmount = order.params.takerTokenAmount.div(2);
-            await exWrapper.fillOrderAsync(order, taker, { fillTakerTokenAmount });
+            const fillTakerTokenAmount = signedOrder.params.takerTokenAmount.div(2);
+            await exWrapper.fillOrderAsync(signedOrder, taker, { fillTakerTokenAmount });
 
-            const res = await exWrapper.fillOrderAsync(order, taker, {
-                fillTakerTokenAmount: order.params.takerTokenAmount,
+            const res = await exWrapper.fillOrderAsync(signedOrder, taker, {
+                fillTakerTokenAmount: signedOrder.params.takerTokenAmount,
             });
             const log = res.logs[0] as LogWithDecodedArgs<LogFillContractEventArgs>;
             expect(log.args.filledTakerTokenAmount).to.be.bignumber.equal(
-                order.params.takerTokenAmount.minus(fillTakerTokenAmount),
+                signedOrder.params.takerTokenAmount.minus(fillTakerTokenAmount),
             );
             const newBalances = await dmyBalances.getAsync();
 
-            expect(newBalances[maker][order.params.makerToken]).to.be.bignumber.equal(
-                balances[maker][order.params.makerToken].minus(order.params.makerTokenAmount),
+            expect(newBalances[maker][signedOrder.params.makerToken]).to.be.bignumber.equal(
+                balances[maker][signedOrder.params.makerToken].minus(signedOrder.params.makerTokenAmount),
             );
-            expect(newBalances[maker][order.params.takerToken]).to.be.bignumber.equal(
-                balances[maker][order.params.takerToken].add(order.params.takerTokenAmount),
+            expect(newBalances[maker][signedOrder.params.takerToken]).to.be.bignumber.equal(
+                balances[maker][signedOrder.params.takerToken].add(signedOrder.params.takerTokenAmount),
             );
             expect(newBalances[maker][zrx.address]).to.be.bignumber.equal(
-                balances[maker][zrx.address].minus(order.params.makerFee),
+                balances[maker][zrx.address].minus(signedOrder.params.makerFee),
             );
-            expect(newBalances[taker][order.params.takerToken]).to.be.bignumber.equal(
-                balances[taker][order.params.takerToken].minus(order.params.takerTokenAmount),
+            expect(newBalances[taker][signedOrder.params.takerToken]).to.be.bignumber.equal(
+                balances[taker][signedOrder.params.takerToken].minus(signedOrder.params.takerTokenAmount),
             );
-            expect(newBalances[taker][order.params.makerToken]).to.be.bignumber.equal(
-                balances[taker][order.params.makerToken].add(order.params.makerTokenAmount),
+            expect(newBalances[taker][signedOrder.params.makerToken]).to.be.bignumber.equal(
+                balances[taker][signedOrder.params.makerToken].add(signedOrder.params.makerTokenAmount),
             );
             expect(newBalances[taker][zrx.address]).to.be.bignumber.equal(
-                balances[taker][zrx.address].minus(order.params.takerFee),
+                balances[taker][zrx.address].minus(signedOrder.params.takerFee),
             );
             expect(newBalances[feeRecipient][zrx.address]).to.be.bignumber.equal(
-                balances[feeRecipient][zrx.address].add(order.params.makerFee.add(order.params.takerFee)),
+                balances[feeRecipient][zrx.address].add(signedOrder.params.makerFee.add(signedOrder.params.takerFee)),
             );
         });
 
         it('should log 1 event with the correct arguments when order has a feeRecipient', async () => {
             const divisor = 2;
-            const res = await exWrapper.fillOrderAsync(order, taker, {
-                fillTakerTokenAmount: order.params.takerTokenAmount.div(divisor),
+            const res = await exWrapper.fillOrderAsync(signedOrder, taker, {
+                fillTakerTokenAmount: signedOrder.params.takerTokenAmount.div(divisor),
             });
             expect(res.logs).to.have.length(1);
 
             const logArgs = (res.logs[0] as LogWithDecodedArgs<LogFillContractEventArgs>).args;
-            const expectedFilledMakerTokenAmount = order.params.makerTokenAmount.div(divisor);
-            const expectedFilledTakerTokenAmount = order.params.takerTokenAmount.div(divisor);
-            const expectedFeeMPaid = order.params.makerFee.div(divisor);
-            const expectedFeeTPaid = order.params.takerFee.div(divisor);
-            const tokensHashBuff = crypto.solSHA3([order.params.makerToken, order.params.takerToken]);
+            const expectedFilledMakerTokenAmount = signedOrder.params.makerTokenAmount.div(divisor);
+            const expectedFilledTakerTokenAmount = signedOrder.params.takerTokenAmount.div(divisor);
+            const expectedFeeMPaid = signedOrder.params.makerFee.div(divisor);
+            const expectedFeeTPaid = signedOrder.params.takerFee.div(divisor);
+            const tokensHashBuff = crypto.solSHA3([signedOrder.params.makerToken, signedOrder.params.takerToken]);
             const expectedTokens = ethUtil.bufferToHex(tokensHashBuff);
 
-            expect(order.params.maker).to.be.equal(logArgs.maker);
+            expect(signedOrder.params.maker).to.be.equal(logArgs.maker);
             expect(taker).to.be.equal(logArgs.taker);
-            expect(order.params.feeRecipient).to.be.equal(logArgs.feeRecipient);
-            expect(order.params.makerToken).to.be.equal(logArgs.makerToken);
-            expect(order.params.takerToken).to.be.equal(logArgs.takerToken);
+            expect(signedOrder.params.feeRecipient).to.be.equal(logArgs.feeRecipient);
+            expect(signedOrder.params.makerToken).to.be.equal(logArgs.makerToken);
+            expect(signedOrder.params.takerToken).to.be.equal(logArgs.takerToken);
             expect(expectedFilledMakerTokenAmount).to.be.bignumber.equal(logArgs.filledMakerTokenAmount);
             expect(expectedFilledTakerTokenAmount).to.be.bignumber.equal(logArgs.filledTakerTokenAmount);
             expect(expectedFeeMPaid).to.be.bignumber.equal(logArgs.paidMakerFee);
             expect(expectedFeeTPaid).to.be.bignumber.equal(logArgs.paidTakerFee);
             expect(expectedTokens).to.be.equal(logArgs.tokens);
-            expect(order.getOrderHashHex()).to.be.equal(logArgs.orderHash);
+            expect(signedOrder.getOrderHashHex()).to.be.equal(logArgs.orderHash);
         });
 
         it('should log 1 event with the correct arguments when order has no feeRecipient', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 feeRecipient: ZeroEx.NULL_ADDRESS,
             });
             const divisor = 2;
-            const res = await exWrapper.fillOrderAsync(order, taker, {
-                fillTakerTokenAmount: order.params.takerTokenAmount.div(divisor),
+            const res = await exWrapper.fillOrderAsync(signedOrder, taker, {
+                fillTakerTokenAmount: signedOrder.params.takerTokenAmount.div(divisor),
             });
             expect(res.logs).to.have.length(1);
 
             const logArgs = (res.logs[0] as LogWithDecodedArgs<LogFillContractEventArgs>).args;
-            const expectedFilledMakerTokenAmount = order.params.makerTokenAmount.div(divisor);
-            const expectedFilledTakerTokenAmount = order.params.takerTokenAmount.div(divisor);
+            const expectedFilledMakerTokenAmount = signedOrder.params.makerTokenAmount.div(divisor);
+            const expectedFilledTakerTokenAmount = signedOrder.params.takerTokenAmount.div(divisor);
             const expectedFeeMPaid = new BigNumber(0);
             const expectedFeeTPaid = new BigNumber(0);
-            const tokensHashBuff = crypto.solSHA3([order.params.makerToken, order.params.takerToken]);
+            const tokensHashBuff = crypto.solSHA3([signedOrder.params.makerToken, signedOrder.params.takerToken]);
             const expectedTokens = ethUtil.bufferToHex(tokensHashBuff);
 
-            expect(order.params.maker).to.be.equal(logArgs.maker);
+            expect(signedOrder.params.maker).to.be.equal(logArgs.maker);
             expect(taker).to.be.equal(logArgs.taker);
-            expect(order.params.feeRecipient).to.be.equal(logArgs.feeRecipient);
-            expect(order.params.makerToken).to.be.equal(logArgs.makerToken);
-            expect(order.params.takerToken).to.be.equal(logArgs.takerToken);
+            expect(signedOrder.params.feeRecipient).to.be.equal(logArgs.feeRecipient);
+            expect(signedOrder.params.makerToken).to.be.equal(logArgs.makerToken);
+            expect(signedOrder.params.takerToken).to.be.equal(logArgs.takerToken);
             expect(expectedFilledMakerTokenAmount).to.be.bignumber.equal(logArgs.filledMakerTokenAmount);
             expect(expectedFilledTakerTokenAmount).to.be.bignumber.equal(logArgs.filledTakerTokenAmount);
             expect(expectedFeeMPaid).to.be.bignumber.equal(logArgs.paidMakerFee);
             expect(expectedFeeTPaid).to.be.bignumber.equal(logArgs.paidTakerFee);
             expect(expectedTokens).to.be.equal(logArgs.tokens);
-            expect(order.getOrderHashHex()).to.be.equal(logArgs.orderHash);
+            expect(signedOrder.getOrderHashHex()).to.be.equal(logArgs.orderHash);
         });
 
         it('should throw when taker is specified and order is claimed by other', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 taker: feeRecipient,
                 makerTokenAmount: ZeroEx.toBaseUnitAmount(new BigNumber(100), 18),
                 takerTokenAmount: ZeroEx.toBaseUnitAmount(new BigNumber(200), 18),
             });
 
-            return expect(exWrapper.fillOrderAsync(order, taker)).to.be.rejectedWith(constants.REVERT);
+            return expect(exWrapper.fillOrderAsync(signedOrder, taker)).to.be.rejectedWith(constants.REVERT);
         });
 
         it('should throw if signature is invalid', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 makerTokenAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
             });
 
-            order.params.r = ethUtil.bufferToHex(ethUtil.sha3('invalidR'));
-            order.params.s = ethUtil.bufferToHex(ethUtil.sha3('invalidS'));
-            return expect(exWrapper.fillOrderAsync(order, taker)).to.be.rejectedWith(constants.REVERT);
+            signedOrder.params.r = ethUtil.bufferToHex(ethUtil.sha3('invalidR'));
+            signedOrder.params.s = ethUtil.bufferToHex(ethUtil.sha3('invalidS'));
+            return expect(exWrapper.fillOrderAsync(signedOrder, taker)).to.be.rejectedWith(constants.REVERT);
         });
 
         it('should throw if makerTokenAmount is 0', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 makerTokenAmount: new BigNumber(0),
             });
 
-            return expect(exWrapper.fillOrderAsync(order, taker)).to.be.rejectedWith(constants.REVERT);
+            return expect(exWrapper.fillOrderAsync(signedOrder, taker)).to.be.rejectedWith(constants.REVERT);
         });
 
         it('should throw if takerTokenAmount is 0', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 takerTokenAmount: new BigNumber(0),
             });
 
-            return expect(exWrapper.fillOrderAsync(order, taker)).to.be.rejectedWith(constants.REVERT);
+            return expect(exWrapper.fillOrderAsync(signedOrder, taker)).to.be.rejectedWith(constants.REVERT);
         });
 
         it('should throw if fillTakerTokenAmount is 0', async () => {
-            order = await orderFactory.newSignedOrderAsync();
+            signedOrder = await orderFactory.newSignedOrderAsync();
 
             return expect(
-                exWrapper.fillOrderAsync(order, taker, {
+                exWrapper.fillOrderAsync(signedOrder, taker, {
                     fillTakerTokenAmount: new BigNumber(0),
                 }),
             ).to.be.rejectedWith(constants.REVERT);
@@ -539,23 +540,23 @@ describe('Exchange', () => {
 
         it('should not change balances if maker balances are too low to fill order and \
                 shouldThrowOnInsufficientBalanceOrAllowance = false', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 makerTokenAmount: ZeroEx.toBaseUnitAmount(new BigNumber(100000), 18),
             });
 
-            await exWrapper.fillOrderAsync(order, taker);
+            await exWrapper.fillOrderAsync(signedOrder, taker);
             const newBalances = await dmyBalances.getAsync();
             expect(newBalances).to.be.deep.equal(balances);
         });
 
         it('should throw if maker balances are too low to fill order and \
                 shouldThrowOnInsufficientBalanceOrAllowance = true', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 makerTokenAmount: ZeroEx.toBaseUnitAmount(new BigNumber(100000), 18),
             });
 
             return expect(
-                exWrapper.fillOrderAsync(order, taker, {
+                exWrapper.fillOrderAsync(signedOrder, taker, {
                     shouldThrowOnInsufficientBalanceOrAllowance: true,
                 }),
             ).to.be.rejectedWith(constants.REVERT);
@@ -563,23 +564,23 @@ describe('Exchange', () => {
 
         it('should not change balances if taker balances are too low to fill order and \
                 shouldThrowOnInsufficientBalanceOrAllowance = false', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 takerTokenAmount: ZeroEx.toBaseUnitAmount(new BigNumber(100000), 18),
             });
 
-            await exWrapper.fillOrderAsync(order, taker);
+            await exWrapper.fillOrderAsync(signedOrder, taker);
             const newBalances = await dmyBalances.getAsync();
             expect(newBalances).to.be.deep.equal(balances);
         });
 
         it('should throw if taker balances are too low to fill order and \
                 shouldThrowOnInsufficientBalanceOrAllowance = true', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 takerTokenAmount: ZeroEx.toBaseUnitAmount(new BigNumber(100000), 18),
             });
 
             return expect(
-                exWrapper.fillOrderAsync(order, taker, {
+                exWrapper.fillOrderAsync(signedOrder, taker, {
                     shouldThrowOnInsufficientBalanceOrAllowance: true,
                 }),
             ).to.be.rejectedWith(constants.REVERT);
@@ -588,7 +589,7 @@ describe('Exchange', () => {
         it('should not change balances if maker allowances are too low to fill order and \
                 shouldThrowOnInsufficientBalanceOrAllowance = false', async () => {
             await rep.approve.sendTransactionAsync(tokenTransferProxy.address, new BigNumber(0), { from: maker });
-            await exWrapper.fillOrderAsync(order, taker);
+            await exWrapper.fillOrderAsync(signedOrder, taker);
             await rep.approve.sendTransactionAsync(tokenTransferProxy.address, INITIAL_ALLOWANCE, {
                 from: maker,
             });
@@ -601,7 +602,7 @@ describe('Exchange', () => {
                 shouldThrowOnInsufficientBalanceOrAllowance = true', async () => {
             await rep.approve.sendTransactionAsync(tokenTransferProxy.address, new BigNumber(0), { from: maker });
             expect(
-                exWrapper.fillOrderAsync(order, taker, {
+                exWrapper.fillOrderAsync(signedOrder, taker, {
                     shouldThrowOnInsufficientBalanceOrAllowance: true,
                 }),
             ).to.be.rejectedWith(constants.REVERT);
@@ -613,7 +614,7 @@ describe('Exchange', () => {
         it('should not change balances if taker allowances are too low to fill order and \
                 shouldThrowOnInsufficientBalanceOrAllowance = false', async () => {
             await dgd.approve.sendTransactionAsync(tokenTransferProxy.address, new BigNumber(0), { from: taker });
-            await exWrapper.fillOrderAsync(order, taker);
+            await exWrapper.fillOrderAsync(signedOrder, taker);
             await dgd.approve.sendTransactionAsync(tokenTransferProxy.address, INITIAL_ALLOWANCE, {
                 from: taker,
             });
@@ -626,7 +627,7 @@ describe('Exchange', () => {
                 shouldThrowOnInsufficientBalanceOrAllowance = true', async () => {
             await dgd.approve.sendTransactionAsync(tokenTransferProxy.address, new BigNumber(0), { from: taker });
             expect(
-                exWrapper.fillOrderAsync(order, taker, {
+                exWrapper.fillOrderAsync(signedOrder, taker, {
                     shouldThrowOnInsufficientBalanceOrAllowance: true,
                 }),
             ).to.be.rejectedWith(constants.REVERT);
@@ -638,12 +639,12 @@ describe('Exchange', () => {
         it('should not change balances if makerToken is ZRX, makerTokenAmount + makerFee > maker balance, \
                 and shouldThrowOnInsufficientBalanceOrAllowance = false', async () => {
             const makerZRXBalance = new BigNumber(balances[maker][zrx.address]);
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 makerToken: zrx.address,
                 makerTokenAmount: makerZRXBalance,
                 makerFee: new BigNumber(1),
             });
-            await exWrapper.fillOrderAsync(order, taker);
+            await exWrapper.fillOrderAsync(signedOrder, taker);
             const newBalances = await dmyBalances.getAsync();
             expect(newBalances).to.be.deep.equal(balances);
         });
@@ -651,12 +652,12 @@ describe('Exchange', () => {
         it('should not change balances if makerToken is ZRX, makerTokenAmount + makerFee > maker allowance, \
                 and shouldThrowOnInsufficientBalanceOrAllowance = false', async () => {
             const makerZRXAllowance = await zrx.allowance(maker, tokenTransferProxy.address);
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 makerToken: zrx.address,
                 makerTokenAmount: new BigNumber(makerZRXAllowance),
                 makerFee: new BigNumber(1),
             });
-            await exWrapper.fillOrderAsync(order, taker);
+            await exWrapper.fillOrderAsync(signedOrder, taker);
             const newBalances = await dmyBalances.getAsync();
             expect(newBalances).to.be.deep.equal(balances);
         });
@@ -664,12 +665,12 @@ describe('Exchange', () => {
         it('should not change balances if takerToken is ZRX, takerTokenAmount + takerFee > taker balance, \
                 and shouldThrowOnInsufficientBalanceOrAllowance = false', async () => {
             const takerZRXBalance = new BigNumber(balances[taker][zrx.address]);
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 takerToken: zrx.address,
                 takerTokenAmount: takerZRXBalance,
                 takerFee: new BigNumber(1),
             });
-            await exWrapper.fillOrderAsync(order, taker);
+            await exWrapper.fillOrderAsync(signedOrder, taker);
             const newBalances = await dmyBalances.getAsync();
             expect(newBalances).to.be.deep.equal(balances);
         });
@@ -677,12 +678,12 @@ describe('Exchange', () => {
         it('should not change balances if takerToken is ZRX, takerTokenAmount + takerFee > taker allowance, \
                 and shouldThrowOnInsufficientBalanceOrAllowance = false', async () => {
             const takerZRXAllowance = await zrx.allowance(taker, tokenTransferProxy.address);
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 takerToken: zrx.address,
                 takerTokenAmount: new BigNumber(takerZRXAllowance),
                 takerFee: new BigNumber(1),
             });
-            await exWrapper.fillOrderAsync(order, taker);
+            await exWrapper.fillOrderAsync(signedOrder, taker);
             const newBalances = await dmyBalances.getAsync();
             expect(newBalances).to.be.deep.equal(balances);
         });
@@ -694,33 +695,33 @@ describe('Exchange', () => {
                 from: taker,
             });
 
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 takerToken: maliciousToken.address,
             });
 
             return expect(
-                exWrapper.fillOrderAsync(order, taker, {
+                exWrapper.fillOrderAsync(signedOrder, taker, {
                     shouldThrowOnInsufficientBalanceOrAllowance: false,
                 }),
             ).to.be.rejectedWith(constants.REVERT);
         });
 
         it('should not change balances if an order is expired', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 expirationTimestampInSec: new BigNumber(Math.floor((Date.now() - 10000) / 1000)),
             });
-            await exWrapper.fillOrderAsync(order, taker);
+            await exWrapper.fillOrderAsync(signedOrder, taker);
 
             const newBalances = await dmyBalances.getAsync();
             expect(newBalances).to.be.deep.equal(balances);
         });
 
         it('should log an error event if an order is expired', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 expirationTimestampInSec: new BigNumber(Math.floor((Date.now() - 10000) / 1000)),
             });
 
-            const res = await exWrapper.fillOrderAsync(order, taker);
+            const res = await exWrapper.fillOrderAsync(signedOrder, taker);
             expect(res.logs).to.have.length(1);
             const log = res.logs[0] as LogWithDecodedArgs<LogErrorContractEventArgs>;
             const errCode = log.args.errorId.toNumber();
@@ -728,10 +729,10 @@ describe('Exchange', () => {
         });
 
         it('should log an error event if no value is filled', async () => {
-            order = await orderFactory.newSignedOrderAsync({});
-            await exWrapper.fillOrderAsync(order, taker);
+            signedOrder = await orderFactory.newSignedOrderAsync({});
+            await exWrapper.fillOrderAsync(signedOrder, taker);
 
-            const res = await exWrapper.fillOrderAsync(order, taker);
+            const res = await exWrapper.fillOrderAsync(signedOrder, taker);
             expect(res.logs).to.have.length(1);
             const log = res.logs[0] as LogWithDecodedArgs<LogErrorContractEventArgs>;
             const errCode = log.args.errorId.toNumber();
@@ -742,43 +743,43 @@ describe('Exchange', () => {
     describe('cancelOrder', () => {
         beforeEach(async () => {
             balances = await dmyBalances.getAsync();
-            order = await orderFactory.newSignedOrderAsync();
+            signedOrder = await orderFactory.newSignedOrderAsync();
         });
 
         it('should throw if not sent by maker', async () => {
-            return expect(exWrapper.cancelOrderAsync(order, taker)).to.be.rejectedWith(constants.REVERT);
+            return expect(exWrapper.cancelOrderAsync(signedOrder, taker)).to.be.rejectedWith(constants.REVERT);
         });
 
         it('should throw if makerTokenAmount is 0', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 makerTokenAmount: new BigNumber(0),
             });
 
-            return expect(exWrapper.cancelOrderAsync(order, maker)).to.be.rejectedWith(constants.REVERT);
+            return expect(exWrapper.cancelOrderAsync(signedOrder, maker)).to.be.rejectedWith(constants.REVERT);
         });
 
         it('should throw if takerTokenAmount is 0', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 takerTokenAmount: new BigNumber(0),
             });
 
-            return expect(exWrapper.cancelOrderAsync(order, maker)).to.be.rejectedWith(constants.REVERT);
+            return expect(exWrapper.cancelOrderAsync(signedOrder, maker)).to.be.rejectedWith(constants.REVERT);
         });
 
         it('should throw if cancelTakerTokenAmount is 0', async () => {
-            order = await orderFactory.newSignedOrderAsync();
+            signedOrder = await orderFactory.newSignedOrderAsync();
 
             return expect(
-                exWrapper.cancelOrderAsync(order, maker, {
+                exWrapper.cancelOrderAsync(signedOrder, maker, {
                     cancelTakerTokenAmount: new BigNumber(0),
                 }),
             ).to.be.rejectedWith(constants.REVERT);
         });
 
         it('should be able to cancel a full order', async () => {
-            await exWrapper.cancelOrderAsync(order, maker);
-            await exWrapper.fillOrderAsync(order, taker, {
-                fillTakerTokenAmount: order.params.takerTokenAmount.div(2),
+            await exWrapper.cancelOrderAsync(signedOrder, maker);
+            await exWrapper.fillOrderAsync(signedOrder, taker, {
+                fillTakerTokenAmount: signedOrder.params.takerTokenAmount.div(2),
             });
 
             const newBalances = await dmyBalances.getAsync();
@@ -786,43 +787,43 @@ describe('Exchange', () => {
         });
 
         it('should be able to cancel part of an order', async () => {
-            const cancelTakerTokenAmount = order.params.takerTokenAmount.div(2);
-            await exWrapper.cancelOrderAsync(order, maker, {
+            const cancelTakerTokenAmount = signedOrder.params.takerTokenAmount.div(2);
+            await exWrapper.cancelOrderAsync(signedOrder, maker, {
                 cancelTakerTokenAmount,
             });
 
-            const res = await exWrapper.fillOrderAsync(order, taker, {
-                fillTakerTokenAmount: order.params.takerTokenAmount,
+            const res = await exWrapper.fillOrderAsync(signedOrder, taker, {
+                fillTakerTokenAmount: signedOrder.params.takerTokenAmount,
             });
             const log = res.logs[0] as LogWithDecodedArgs<LogFillContractEventArgs>;
             expect(log.args.filledTakerTokenAmount).to.be.bignumber.equal(
-                order.params.takerTokenAmount.minus(cancelTakerTokenAmount),
+                signedOrder.params.takerTokenAmount.minus(cancelTakerTokenAmount),
             );
 
             const newBalances = await dmyBalances.getAsync();
             const cancelMakerTokenAmount = cancelTakerTokenAmount
-                .times(order.params.makerTokenAmount)
-                .dividedToIntegerBy(order.params.takerTokenAmount);
-            const paidMakerFee = order.params.makerFee
+                .times(signedOrder.params.makerTokenAmount)
+                .dividedToIntegerBy(signedOrder.params.takerTokenAmount);
+            const paidMakerFee = signedOrder.params.makerFee
                 .times(cancelMakerTokenAmount)
-                .dividedToIntegerBy(order.params.makerTokenAmount);
-            const paidTakerFee = order.params.takerFee
+                .dividedToIntegerBy(signedOrder.params.makerTokenAmount);
+            const paidTakerFee = signedOrder.params.takerFee
                 .times(cancelMakerTokenAmount)
-                .dividedToIntegerBy(order.params.makerTokenAmount);
-            expect(newBalances[maker][order.params.makerToken]).to.be.bignumber.equal(
-                balances[maker][order.params.makerToken].minus(cancelMakerTokenAmount),
+                .dividedToIntegerBy(signedOrder.params.makerTokenAmount);
+            expect(newBalances[maker][signedOrder.params.makerToken]).to.be.bignumber.equal(
+                balances[maker][signedOrder.params.makerToken].minus(cancelMakerTokenAmount),
             );
-            expect(newBalances[maker][order.params.takerToken]).to.be.bignumber.equal(
-                balances[maker][order.params.takerToken].add(cancelTakerTokenAmount),
+            expect(newBalances[maker][signedOrder.params.takerToken]).to.be.bignumber.equal(
+                balances[maker][signedOrder.params.takerToken].add(cancelTakerTokenAmount),
             );
             expect(newBalances[maker][zrx.address]).to.be.bignumber.equal(
                 balances[maker][zrx.address].minus(paidMakerFee),
             );
-            expect(newBalances[taker][order.params.takerToken]).to.be.bignumber.equal(
-                balances[taker][order.params.takerToken].minus(cancelTakerTokenAmount),
+            expect(newBalances[taker][signedOrder.params.takerToken]).to.be.bignumber.equal(
+                balances[taker][signedOrder.params.takerToken].minus(cancelTakerTokenAmount),
             );
-            expect(newBalances[taker][order.params.makerToken]).to.be.bignumber.equal(
-                balances[taker][order.params.makerToken].add(cancelMakerTokenAmount),
+            expect(newBalances[taker][signedOrder.params.makerToken]).to.be.bignumber.equal(
+                balances[taker][signedOrder.params.makerToken].add(cancelMakerTokenAmount),
             );
             expect(newBalances[taker][zrx.address]).to.be.bignumber.equal(
                 balances[taker][zrx.address].minus(paidTakerFee),
@@ -834,32 +835,32 @@ describe('Exchange', () => {
 
         it('should log 1 event with correct arguments', async () => {
             const divisor = 2;
-            const res = await exWrapper.cancelOrderAsync(order, maker, {
-                cancelTakerTokenAmount: order.params.takerTokenAmount.div(divisor),
+            const res = await exWrapper.cancelOrderAsync(signedOrder, maker, {
+                cancelTakerTokenAmount: signedOrder.params.takerTokenAmount.div(divisor),
             });
             expect(res.logs).to.have.length(1);
 
             const log = res.logs[0] as LogWithDecodedArgs<LogCancelContractEventArgs>;
             const logArgs = log.args;
-            const expectedCancelledMakerTokenAmount = order.params.makerTokenAmount.div(divisor);
-            const expectedCancelledTakerTokenAmount = order.params.takerTokenAmount.div(divisor);
-            const tokensHashBuff = crypto.solSHA3([order.params.makerToken, order.params.takerToken]);
+            const expectedCancelledMakerTokenAmount = signedOrder.params.makerTokenAmount.div(divisor);
+            const expectedCancelledTakerTokenAmount = signedOrder.params.takerTokenAmount.div(divisor);
+            const tokensHashBuff = crypto.solSHA3([signedOrder.params.makerToken, signedOrder.params.takerToken]);
             const expectedTokens = ethUtil.bufferToHex(tokensHashBuff);
 
-            expect(order.params.maker).to.be.equal(logArgs.maker);
-            expect(order.params.feeRecipient).to.be.equal(logArgs.feeRecipient);
-            expect(order.params.makerToken).to.be.equal(logArgs.makerToken);
-            expect(order.params.takerToken).to.be.equal(logArgs.takerToken);
+            expect(signedOrder.params.maker).to.be.equal(logArgs.maker);
+            expect(signedOrder.params.feeRecipient).to.be.equal(logArgs.feeRecipient);
+            expect(signedOrder.params.makerToken).to.be.equal(logArgs.makerToken);
+            expect(signedOrder.params.takerToken).to.be.equal(logArgs.takerToken);
             expect(expectedCancelledMakerTokenAmount).to.be.bignumber.equal(logArgs.cancelledMakerTokenAmount);
             expect(expectedCancelledTakerTokenAmount).to.be.bignumber.equal(logArgs.cancelledTakerTokenAmount);
             expect(expectedTokens).to.be.equal(logArgs.tokens);
-            expect(order.getOrderHashHex()).to.be.equal(logArgs.orderHash);
+            expect(signedOrder.getOrderHashHex()).to.be.equal(logArgs.orderHash);
         });
 
         it('should not log events if no value is cancelled', async () => {
-            await exWrapper.cancelOrderAsync(order, maker);
+            await exWrapper.cancelOrderAsync(signedOrder, maker);
 
-            const res = await exWrapper.cancelOrderAsync(order, maker);
+            const res = await exWrapper.cancelOrderAsync(signedOrder, maker);
             expect(res.logs).to.have.length(1);
             const log = res.logs[0] as LogWithDecodedArgs<LogErrorContractEventArgs>;
             const errCode = log.args.errorId.toNumber();
@@ -867,11 +868,11 @@ describe('Exchange', () => {
         });
 
         it('should not log events if order is expired', async () => {
-            order = await orderFactory.newSignedOrderAsync({
+            signedOrder = await orderFactory.newSignedOrderAsync({
                 expirationTimestampInSec: new BigNumber(Math.floor((Date.now() - 10000) / 1000)),
             });
 
-            const res = await exWrapper.cancelOrderAsync(order, maker);
+            const res = await exWrapper.cancelOrderAsync(signedOrder, maker);
             expect(res.logs).to.have.length(1);
             const log = res.logs[0] as LogWithDecodedArgs<LogErrorContractEventArgs>;
             const errCode = log.args.errorId.toNumber();
diff --git a/packages/contracts/test/exchange/helpers.ts b/packages/contracts/test/exchange/helpers.ts
index e2e35ece8..263a74911 100644
--- a/packages/contracts/test/exchange/helpers.ts
+++ b/packages/contracts/test/exchange/helpers.ts
@@ -10,6 +10,7 @@ import { constants } from '../../util/constants';
 import { ExchangeWrapper } from '../../util/exchange_wrapper';
 import { Order } from '../../util/order';
 import { OrderFactory } from '../../util/order_factory';
+import { SignedOrder } from '../../util/signed_order';
 import { ContractName } from '../../util/types';
 import { chaiSetup } from '../utils/chai_setup';
 import { deployer } from '../utils/deployer';
@@ -25,7 +26,7 @@ describe('Exchange', () => {
     let maker: string;
     let feeRecipient: string;
 
-    let order: Order;
+    let signedOrder: SignedOrder;
     let exchangeWrapper: ExchangeWrapper;
     let orderFactory: OrderFactory;
 
@@ -59,7 +60,7 @@ describe('Exchange', () => {
             takerFee: ZeroEx.toBaseUnitAmount(new BigNumber(1), 18),
         };
         orderFactory = new OrderFactory(web3Wrapper, defaultOrderParams);
-        order = await orderFactory.newSignedOrderAsync();
+        signedOrder = await orderFactory.newSignedOrderAsync();
     });
 
     beforeEach(async () => {
@@ -70,28 +71,28 @@ describe('Exchange', () => {
     });
     describe('getOrderHash', () => {
         it('should output the correct orderHash', async () => {
-            const orderHashHex = await exchangeWrapper.getOrderHashAsync(order);
-            expect(order.getOrderHashHex()).to.be.equal(orderHashHex);
+            const orderHashHex = await exchangeWrapper.getOrderHashAsync(signedOrder);
+            expect(signedOrder.getOrderHashHex()).to.be.equal(orderHashHex);
         });
     });
 
     describe('isValidSignature', () => {
         beforeEach(async () => {
-            order = await orderFactory.newSignedOrderAsync();
+            signedOrder = await orderFactory.newSignedOrderAsync();
         });
 
         it('should return true with a valid signature', async () => {
-            const success = await exchangeWrapper.isValidSignatureAsync(order);
-            const isValidSignature = order.isValidSignature();
+            const success = await exchangeWrapper.isValidSignatureAsync(signedOrder);
+            const isValidSignature = signedOrder.isValidSignature();
             expect(isValidSignature).to.be.true();
             expect(success).to.be.true();
         });
 
         it('should return false with an invalid signature', async () => {
-            order.params.r = ethUtil.bufferToHex(ethUtil.sha3('invalidR'));
-            order.params.s = ethUtil.bufferToHex(ethUtil.sha3('invalidS'));
-            const success = await exchangeWrapper.isValidSignatureAsync(order);
-            expect(order.isValidSignature()).to.be.false();
+            signedOrder.params.r = ethUtil.bufferToHex(ethUtil.sha3('invalidR'));
+            signedOrder.params.s = ethUtil.bufferToHex(ethUtil.sha3('invalidS'));
+            const success = await exchangeWrapper.isValidSignatureAsync(signedOrder);
+            expect(signedOrder.isValidSignature()).to.be.false();
             expect(success).to.be.false();
         });
     });
diff --git a/packages/contracts/test/exchange/wrapper.ts b/packages/contracts/test/exchange/wrapper.ts
index b1851a55c..02d722ed5 100644
--- a/packages/contracts/test/exchange/wrapper.ts
+++ b/packages/contracts/test/exchange/wrapper.ts
@@ -15,6 +15,7 @@ import { constants } from '../../util/constants';
 import { ExchangeWrapper } from '../../util/exchange_wrapper';
 import { Order } from '../../util/order';
 import { OrderFactory } from '../../util/order_factory';
+import { SignedOrder } from '../../util/signed_order';
 import { BalancesByOwner, ContractName } from '../../util/types';
 import { chaiSetup } from '../utils/chai_setup';
 import { deployer } from '../utils/deployer';
@@ -173,7 +174,7 @@ describe('Exchange', () => {
     });
 
     describe('batch functions', () => {
-        let orders: Order[];
+        let orders: SignedOrder[];
         beforeEach(async () => {
             orders = await Promise.all([
                 orderFactory.newSignedOrderAsync(),
diff --git a/packages/contracts/util/exchange_wrapper.ts b/packages/contracts/util/exchange_wrapper.ts
index e44a0eab6..ff263246f 100644
--- a/packages/contracts/util/exchange_wrapper.ts
+++ b/packages/contracts/util/exchange_wrapper.ts
@@ -6,7 +6,7 @@ import * as Web3 from 'web3';
 import { ExchangeContract } from '../src/contract_wrappers/generated/exchange';
 
 import { formatters } from './formatters';
-import { Order } from './order';
+import { SignedOrder } from './signed_order';
 
 export class ExchangeWrapper {
     private _exchange: ExchangeContract;
@@ -16,7 +16,7 @@ export class ExchangeWrapper {
         this._zeroEx = zeroEx;
     }
     public async fillOrderAsync(
-        order: Order,
+        signedOrder: SignedOrder,
         from: string,
         opts: {
             fillTakerTokenAmount?: BigNumber;
@@ -24,15 +24,15 @@ export class ExchangeWrapper {
         } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
         const shouldThrowOnInsufficientBalanceOrAllowance = !!opts.shouldThrowOnInsufficientBalanceOrAllowance;
-        const params = order.createFill(shouldThrowOnInsufficientBalanceOrAllowance, opts.fillTakerTokenAmount);
+        const params = signedOrder.createFill(shouldThrowOnInsufficientBalanceOrAllowance, opts.fillTakerTokenAmount);
         const txHash = await this._exchange.fillOrder.sendTransactionAsync(
             params.orderAddresses,
             params.orderValues,
             params.fillTakerTokenAmount,
             params.shouldThrowOnInsufficientBalanceOrAllowance,
-            params.v as number,
-            params.r as string,
-            params.s as string,
+            params.v,
+            params.r,
+            params.s,
             { from },
         );
         const tx = await this._zeroEx.awaitTransactionMinedAsync(txHash);
@@ -41,11 +41,11 @@ export class ExchangeWrapper {
         return tx;
     }
     public async cancelOrderAsync(
-        order: Order,
+        signedOrder: SignedOrder,
         from: string,
         opts: { cancelTakerTokenAmount?: BigNumber } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
-        const params = order.createCancel(opts.cancelTakerTokenAmount);
+        const params = signedOrder.createCancel(opts.cancelTakerTokenAmount);
         const txHash = await this._exchange.cancelOrder.sendTransactionAsync(
             params.orderAddresses,
             params.orderValues,
@@ -58,19 +58,19 @@ export class ExchangeWrapper {
         return tx;
     }
     public async fillOrKillOrderAsync(
-        order: Order,
+        signedOrder: SignedOrder,
         from: string,
         opts: { fillTakerTokenAmount?: BigNumber } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
         const shouldThrowOnInsufficientBalanceOrAllowance = true;
-        const params = order.createFill(shouldThrowOnInsufficientBalanceOrAllowance, opts.fillTakerTokenAmount);
+        const params = signedOrder.createFill(shouldThrowOnInsufficientBalanceOrAllowance, opts.fillTakerTokenAmount);
         const txHash = await this._exchange.fillOrKillOrder.sendTransactionAsync(
             params.orderAddresses,
             params.orderValues,
             params.fillTakerTokenAmount,
-            params.v as number,
-            params.r as string,
-            params.s as string,
+            params.v,
+            params.r,
+            params.s,
             { from },
         );
         const tx = await this._zeroEx.awaitTransactionMinedAsync(txHash);
@@ -79,7 +79,7 @@ export class ExchangeWrapper {
         return tx;
     }
     public async batchFillOrdersAsync(
-        orders: Order[],
+        orders: SignedOrder[],
         from: string,
         opts: {
             fillTakerTokenAmounts?: BigNumber[];
@@ -108,7 +108,7 @@ export class ExchangeWrapper {
         return tx;
     }
     public async batchFillOrKillOrdersAsync(
-        orders: Order[],
+        orders: SignedOrder[],
         from: string,
         opts: { fillTakerTokenAmounts?: BigNumber[]; shouldThrowOnInsufficientBalanceOrAllowance?: boolean } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
@@ -133,7 +133,7 @@ export class ExchangeWrapper {
         return tx;
     }
     public async fillOrdersUpToAsync(
-        orders: Order[],
+        orders: SignedOrder[],
         from: string,
         opts: { fillTakerTokenAmount: BigNumber; shouldThrowOnInsufficientBalanceOrAllowance?: boolean },
     ): Promise<TransactionReceiptWithDecodedLogs> {
@@ -159,7 +159,7 @@ export class ExchangeWrapper {
         return tx;
     }
     public async batchCancelOrdersAsync(
-        orders: Order[],
+        orders: SignedOrder[],
         from: string,
         opts: { cancelTakerTokenAmounts?: BigNumber[] } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
@@ -175,19 +175,19 @@ export class ExchangeWrapper {
         _.each(tx.logs, log => wrapLogBigNumbers(log));
         return tx;
     }
-    public async getOrderHashAsync(order: Order): Promise<string> {
+    public async getOrderHashAsync(signedOrder: SignedOrder): Promise<string> {
         const shouldThrowOnInsufficientBalanceOrAllowance = false;
-        const params = order.createFill(shouldThrowOnInsufficientBalanceOrAllowance);
+        const params = signedOrder.createFill(shouldThrowOnInsufficientBalanceOrAllowance);
         const orderHash = await this._exchange.getOrderHash(params.orderAddresses, params.orderValues);
         return orderHash;
     }
-    public async isValidSignatureAsync(order: Order): Promise<boolean> {
+    public async isValidSignatureAsync(signedOrder: SignedOrder): Promise<boolean> {
         const isValidSignature = await this._exchange.isValidSignature(
-            order.params.maker,
-            order.getOrderHashHex(),
-            order.params.v as number,
-            order.params.r as string,
-            order.params.s as string,
+            signedOrder.params.maker,
+            signedOrder.getOrderHashHex(),
+            signedOrder.params.v,
+            signedOrder.params.r,
+            signedOrder.params.s,
         );
         return isValidSignature;
     }
diff --git a/packages/contracts/util/formatters.ts b/packages/contracts/util/formatters.ts
index e16fe8d45..6c225268e 100644
--- a/packages/contracts/util/formatters.ts
+++ b/packages/contracts/util/formatters.ts
@@ -1,12 +1,12 @@
 import { BigNumber } from '@0xproject/utils';
 import * as _ from 'lodash';
 
-import { Order } from './order';
+import { SignedOrder } from './signed_order';
 import { BatchCancelOrders, BatchFillOrders, FillOrdersUpTo } from './types';
 
 export const formatters = {
     createBatchFill(
-        orders: Order[],
+        orders: SignedOrder[],
         shouldThrowOnInsufficientBalanceOrAllowance: boolean,
         fillTakerTokenAmounts: BigNumber[] = [],
     ) {
@@ -35,9 +35,9 @@ export const formatters = {
                 order.params.expirationTimestampInSec,
                 order.params.salt,
             ]);
-            batchFill.v.push(order.params.v as number);
-            batchFill.r.push(order.params.r as string);
-            batchFill.s.push(order.params.s as string);
+            batchFill.v.push(order.params.v);
+            batchFill.r.push(order.params.r);
+            batchFill.s.push(order.params.s);
             if (fillTakerTokenAmounts.length < orders.length) {
                 batchFill.fillTakerTokenAmounts.push(order.params.takerTokenAmount);
             }
@@ -45,7 +45,7 @@ export const formatters = {
         return batchFill;
     },
     createFillUpTo(
-        orders: Order[],
+        orders: SignedOrder[],
         shouldThrowOnInsufficientBalanceOrAllowance: boolean,
         fillTakerTokenAmount: BigNumber,
     ) {
@@ -74,13 +74,13 @@ export const formatters = {
                 order.params.expirationTimestampInSec,
                 order.params.salt,
             ]);
-            fillUpTo.v.push(order.params.v as number);
-            fillUpTo.r.push(order.params.r as string);
-            fillUpTo.s.push(order.params.s as string);
+            fillUpTo.v.push(order.params.v);
+            fillUpTo.r.push(order.params.r);
+            fillUpTo.s.push(order.params.s);
         });
         return fillUpTo;
     },
-    createBatchCancel(orders: Order[], cancelTakerTokenAmounts: BigNumber[] = []) {
+    createBatchCancel(orders: SignedOrder[], cancelTakerTokenAmounts: BigNumber[] = []) {
         const batchCancel: BatchCancelOrders = {
             orderAddresses: [],
             orderValues: [],
diff --git a/packages/contracts/util/order.ts b/packages/contracts/util/order.ts
index 12f10fa4e..6d412e2af 100644
--- a/packages/contracts/util/order.ts
+++ b/packages/contracts/util/order.ts
@@ -4,6 +4,7 @@ import ethUtil = require('ethereumjs-util');
 import * as _ from 'lodash';
 
 import { crypto } from './crypto';
+import { SignedOrder } from './signed_order';
 import { OrderParams } from './types';
 
 export class Order {
@@ -13,76 +14,17 @@ export class Order {
         this.params = params;
         this._web3Wrapper = web3Wrapper;
     }
-    public isValidSignature() {
-        const { v, r, s } = this.params;
-        if (_.isUndefined(v) || _.isUndefined(r) || _.isUndefined(s)) {
-            throw new Error('Cannot call isValidSignature on unsigned order');
-        }
-        const orderHash = this.getOrderHashHex();
-        const msgHash = ethUtil.hashPersonalMessage(ethUtil.toBuffer(orderHash));
-        try {
-            const pubKey = ethUtil.ecrecover(msgHash, v, ethUtil.toBuffer(r), ethUtil.toBuffer(s));
-            const recoveredAddress = ethUtil.bufferToHex(ethUtil.pubToAddress(pubKey));
-            return recoveredAddress === this.params.maker;
-        } catch (err) {
-            return false;
-        }
-    }
-    public async signAsync() {
+    public async signAsync(): Promise<SignedOrder> {
         const orderHash = this.getOrderHashHex();
         const signature = await this._web3Wrapper.signTransactionAsync(this.params.maker, orderHash);
         const { v, r, s } = ethUtil.fromRpcSig(signature);
-        this.params = _.assign(this.params, {
+        const signedOrderParams = _.assign(this.params, {
             v,
             r: ethUtil.bufferToHex(r),
             s: ethUtil.bufferToHex(s),
         });
-    }
-    public createFill(shouldThrowOnInsufficientBalanceOrAllowance?: boolean, fillTakerTokenAmount?: BigNumber) {
-        const fill = {
-            orderAddresses: [
-                this.params.maker,
-                this.params.taker,
-                this.params.makerToken,
-                this.params.takerToken,
-                this.params.feeRecipient,
-            ],
-            orderValues: [
-                this.params.makerTokenAmount,
-                this.params.takerTokenAmount,
-                this.params.makerFee,
-                this.params.takerFee,
-                this.params.expirationTimestampInSec,
-                this.params.salt,
-            ],
-            fillTakerTokenAmount: fillTakerTokenAmount || this.params.takerTokenAmount,
-            shouldThrowOnInsufficientBalanceOrAllowance: !!shouldThrowOnInsufficientBalanceOrAllowance,
-            v: this.params.v,
-            r: this.params.r,
-            s: this.params.s,
-        };
-        return fill;
-    }
-    public createCancel(cancelTakerTokenAmount?: BigNumber) {
-        const cancel = {
-            orderAddresses: [
-                this.params.maker,
-                this.params.taker,
-                this.params.makerToken,
-                this.params.takerToken,
-                this.params.feeRecipient,
-            ],
-            orderValues: [
-                this.params.makerTokenAmount,
-                this.params.takerTokenAmount,
-                this.params.makerFee,
-                this.params.takerFee,
-                this.params.expirationTimestampInSec,
-                this.params.salt,
-            ],
-            cancelTakerTokenAmount: cancelTakerTokenAmount || this.params.takerTokenAmount,
-        };
-        return cancel;
+        const signedOrder = new SignedOrder(this._web3Wrapper, signedOrderParams);
+        return signedOrder;
     }
     public getOrderHashHex(): string {
         const orderHash = crypto.solSHA3([
diff --git a/packages/contracts/util/order_factory.ts b/packages/contracts/util/order_factory.ts
index 2b50f13e8..788f60a88 100644
--- a/packages/contracts/util/order_factory.ts
+++ b/packages/contracts/util/order_factory.ts
@@ -4,6 +4,7 @@ import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import * as _ from 'lodash';
 
 import { Order } from './order';
+import { SignedOrder } from './signed_order';
 import { DefaultOrderParams, OptionalOrderParams, OrderParams } from './types';
 
 export class OrderFactory {
@@ -13,7 +14,7 @@ export class OrderFactory {
         this._defaultOrderParams = defaultOrderParams;
         this._web3Wrapper = web3Wrapper;
     }
-    public async newSignedOrderAsync(customOrderParams: OptionalOrderParams = {}): Promise<Order> {
+    public async newSignedOrderAsync(customOrderParams: OptionalOrderParams = {}): Promise<SignedOrder> {
         const randomExpiration = new BigNumber(Math.floor((Date.now() + Math.random() * 100000000000) / 1000));
         const orderParams: OrderParams = _.assign(
             {},
@@ -26,7 +27,7 @@ export class OrderFactory {
             customOrderParams,
         );
         const order = new Order(this._web3Wrapper, orderParams);
-        await order.signAsync();
-        return order;
+        const signedOrder = await order.signAsync();
+        return signedOrder;
     }
 }
diff --git a/packages/contracts/util/signed_order.ts b/packages/contracts/util/signed_order.ts
new file mode 100644
index 000000000..a84e0686c
--- /dev/null
+++ b/packages/contracts/util/signed_order.ts
@@ -0,0 +1,92 @@
+import { BigNumber } from '@0xproject/utils';
+import { Web3Wrapper } from '@0xproject/web3-wrapper';
+import ethUtil = require('ethereumjs-util');
+import * as _ from 'lodash';
+
+import { crypto } from './crypto';
+import { SignedOrderParams } from './types';
+
+export class SignedOrder {
+    public params: SignedOrderParams;
+    private _web3Wrapper: Web3Wrapper;
+    constructor(web3Wrapper: Web3Wrapper, params: SignedOrderParams) {
+        this.params = params;
+        this._web3Wrapper = web3Wrapper;
+    }
+    public isValidSignature() {
+        const { v, r, s } = this.params;
+        const orderHash = this.getOrderHashHex();
+        const msgHash = ethUtil.hashPersonalMessage(ethUtil.toBuffer(orderHash));
+        try {
+            const pubKey = ethUtil.ecrecover(msgHash, v, ethUtil.toBuffer(r), ethUtil.toBuffer(s));
+            const recoveredAddress = ethUtil.bufferToHex(ethUtil.pubToAddress(pubKey));
+            return recoveredAddress === this.params.maker;
+        } catch (err) {
+            return false;
+        }
+    }
+    public createFill(shouldThrowOnInsufficientBalanceOrAllowance?: boolean, fillTakerTokenAmount?: BigNumber) {
+        const fill = {
+            orderAddresses: [
+                this.params.maker,
+                this.params.taker,
+                this.params.makerToken,
+                this.params.takerToken,
+                this.params.feeRecipient,
+            ],
+            orderValues: [
+                this.params.makerTokenAmount,
+                this.params.takerTokenAmount,
+                this.params.makerFee,
+                this.params.takerFee,
+                this.params.expirationTimestampInSec,
+                this.params.salt,
+            ],
+            fillTakerTokenAmount: fillTakerTokenAmount || this.params.takerTokenAmount,
+            shouldThrowOnInsufficientBalanceOrAllowance: !!shouldThrowOnInsufficientBalanceOrAllowance,
+            v: this.params.v,
+            r: this.params.r,
+            s: this.params.s,
+        };
+        return fill;
+    }
+    public createCancel(cancelTakerTokenAmount?: BigNumber) {
+        const cancel = {
+            orderAddresses: [
+                this.params.maker,
+                this.params.taker,
+                this.params.makerToken,
+                this.params.takerToken,
+                this.params.feeRecipient,
+            ],
+            orderValues: [
+                this.params.makerTokenAmount,
+                this.params.takerTokenAmount,
+                this.params.makerFee,
+                this.params.takerFee,
+                this.params.expirationTimestampInSec,
+                this.params.salt,
+            ],
+            cancelTakerTokenAmount: cancelTakerTokenAmount || this.params.takerTokenAmount,
+        };
+        return cancel;
+    }
+    public getOrderHashHex(): string {
+        const orderHash = crypto.solSHA3([
+            this.params.exchangeContractAddress,
+            this.params.maker,
+            this.params.taker,
+            this.params.makerToken,
+            this.params.takerToken,
+            this.params.feeRecipient,
+            this.params.makerTokenAmount,
+            this.params.takerTokenAmount,
+            this.params.makerFee,
+            this.params.takerFee,
+            this.params.expirationTimestampInSec,
+            this.params.salt,
+        ]);
+        const orderHashHex = ethUtil.bufferToHex(orderHash);
+        return orderHashHex;
+    }
+}
diff --git a/packages/contracts/util/types.ts b/packages/contracts/util/types.ts
index 5d474b596..1bd8940ad 100644
--- a/packages/contracts/util/types.ts
+++ b/packages/contracts/util/types.ts
@@ -76,9 +76,12 @@ export interface OrderParams {
     takerFee: BigNumber;
     expirationTimestampInSec: BigNumber;
     salt: BigNumber;
-    v?: number;
-    r?: string;
-    s?: string;
+}
+
+export interface SignedOrderParams extends OrderParams {
+    v: number;
+    r: string;
+    s: string;
 }
 
 export interface TransactionDataParams {