Minimize unnecessary type assertions

12 files changed, 248 insertions, 366 deletions

diff --git a/packages/contract-wrappers/src/fetchers/asset_balance_and_proxy_allowance_fetcher.ts b/packages/contract-wrappers/src/fetchers/asset_balance_and_proxy_allowance_fetcher.ts
index 376004f52..1ff130a48 100644
--- a/packages/contract-wrappers/src/fetchers/asset_balance_and_proxy_allowance_fetcher.ts
+++ b/packages/contract-wrappers/src/fetchers/asset_balance_and_proxy_allowance_fetcher.ts
@@ -1,6 +1,4 @@
-// tslint:disable:no-unnecessary-type-assertion
 import { AbstractBalanceAndProxyAllowanceFetcher, assetDataUtils } from '@0x/order-utils';
-import { AssetProxyId, ERC20AssetData, ERC721AssetData, MultiAssetData } from '@0x/types';
 import { BigNumber } from '@0x/utils';
 import { BlockParamLiteral } from 'ethereum-types';
 import * as _ from 'lodash';
@@ -20,99 +18,73 @@ export class AssetBalanceAndProxyAllowanceFetcher implements AbstractBalanceAndP
     public async getBalanceAsync(assetData: string, userAddress: string): Promise<BigNumber> {
         const decodedAssetData = assetDataUtils.decodeAssetDataOrThrow(assetData);
         let balance: BigNumber | undefined;
-        switch (decodedAssetData.assetProxyId) {
-            case AssetProxyId.ERC20:
-                const decodedERC20AssetData = decodedAssetData as ERC20AssetData;
-                balance = await this._erc20Token.getBalanceAsync(decodedERC20AssetData.tokenAddress, userAddress, {
+        if (assetDataUtils.isERC20AssetData(decodedAssetData)) {
+            balance = await this._erc20Token.getBalanceAsync(decodedAssetData.tokenAddress, userAddress, {
+                defaultBlock: this._stateLayer,
+            });
+        } else if (assetDataUtils.isERC721AssetData(decodedAssetData)) {
+            const tokenOwner = await this._erc721Token.getOwnerOfAsync(
+                decodedAssetData.tokenAddress,
+                decodedAssetData.tokenId,
+                {
                     defaultBlock: this._stateLayer,
-                });
-                break;
-            case AssetProxyId.ERC721:
-                const decodedERC721AssetData = decodedAssetData as ERC721AssetData;
-                const tokenOwner = await this._erc721Token.getOwnerOfAsync(
-                    decodedERC721AssetData.tokenAddress,
-                    decodedERC721AssetData.tokenId,
-                    {
-                        defaultBlock: this._stateLayer,
-                    },
-                );
-                balance = tokenOwner === userAddress ? new BigNumber(1) : new BigNumber(0);
-                break;
-            case AssetProxyId.MultiAsset:
-                // The `balance` for MultiAssetData is the total units of the entire `assetData` that are held by the `userAddress`.
-                for (const [
-                    index,
+                },
+            );
+            balance = tokenOwner === userAddress ? new BigNumber(1) : new BigNumber(0);
+        } else if (assetDataUtils.isMultiAssetData(decodedAssetData)) {
+            // The `balance` for MultiAssetData is the total units of the entire `assetData` that are held by the `userAddress`.
+            for (const [index, nestedAssetDataElement] of decodedAssetData.nestedAssetData.entries()) {
+                const nestedAmountElement = decodedAssetData.amounts[index];
+                const nestedAssetBalance = (await this.getBalanceAsync(
                     nestedAssetDataElement,
-                ] of (decodedAssetData as MultiAssetData).nestedAssetData.entries()) {
-                    const nestedAmountElement = (decodedAssetData as MultiAssetData).amounts[index];
-                    const nestedAssetBalance = (await this.getBalanceAsync(
-                        nestedAssetDataElement,
-                        userAddress,
-                    )).dividedToIntegerBy(nestedAmountElement);
-                    if (_.isUndefined(balance) || nestedAssetBalance.lessThan(balance)) {
-                        balance = nestedAssetBalance;
-                    }
+                    userAddress,
+                )).dividedToIntegerBy(nestedAmountElement);
+                if (_.isUndefined(balance) || nestedAssetBalance.lessThan(balance)) {
+                    balance = nestedAssetBalance;
                 }
-                break;
-            default:
-                throw new Error(`Proxy with id ${decodedAssetData.assetProxyId} not supported`);
+            }
         }
         return balance as BigNumber;
     }
     public async getProxyAllowanceAsync(assetData: string, userAddress: string): Promise<BigNumber> {
         const decodedAssetData = assetDataUtils.decodeAssetDataOrThrow(assetData);
         let proxyAllowance: BigNumber | undefined;
-        switch (decodedAssetData.assetProxyId) {
-            case AssetProxyId.ERC20:
-                const decodedERC20AssetData = decodedAssetData as ERC20AssetData;
-                proxyAllowance = await this._erc20Token.getProxyAllowanceAsync(
-                    decodedERC20AssetData.tokenAddress,
-                    userAddress,
-                    {
-                        defaultBlock: this._stateLayer,
-                    },
-                );
-                break;
-            case AssetProxyId.ERC721:
-                const decodedERC721AssetData = decodedAssetData as ERC721AssetData;
-                const isApprovedForAll = await this._erc721Token.isProxyApprovedForAllAsync(
-                    decodedERC721AssetData.tokenAddress,
-                    userAddress,
+        if (assetDataUtils.isERC20AssetData(decodedAssetData)) {
+            proxyAllowance = await this._erc20Token.getProxyAllowanceAsync(decodedAssetData.tokenAddress, userAddress, {
+                defaultBlock: this._stateLayer,
+            });
+        } else if (assetDataUtils.isERC721AssetData(decodedAssetData)) {
+            const isApprovedForAll = await this._erc721Token.isProxyApprovedForAllAsync(
+                decodedAssetData.tokenAddress,
+                userAddress,
+                {
+                    defaultBlock: this._stateLayer,
+                },
+            );
+            if (isApprovedForAll) {
+                return new BigNumber(this._erc20Token.UNLIMITED_ALLOWANCE_IN_BASE_UNITS);
+            } else {
+                const isApproved = await this._erc721Token.isProxyApprovedAsync(
+                    decodedAssetData.tokenAddress,
+                    decodedAssetData.tokenId,
                     {
                         defaultBlock: this._stateLayer,
                     },
                 );
-                if (isApprovedForAll) {
-                    return new BigNumber(this._erc20Token.UNLIMITED_ALLOWANCE_IN_BASE_UNITS);
-                } else {
-                    const isApproved = await this._erc721Token.isProxyApprovedAsync(
-                        decodedERC721AssetData.tokenAddress,
-                        decodedERC721AssetData.tokenId,
-                        {
-                            defaultBlock: this._stateLayer,
-                        },
-                    );
-                    proxyAllowance = isApproved ? new BigNumber(1) : new BigNumber(0);
-                }
-                break;
-            case AssetProxyId.MultiAsset:
-                // The `proxyAllowance` for MultiAssetData is the total units of the entire `assetData` that the proxies have been approved to spend by the `userAddress`.
-                for (const [
-                    index,
+                proxyAllowance = isApproved ? new BigNumber(1) : new BigNumber(0);
+            }
+        } else if (assetDataUtils.isMultiAssetData(decodedAssetData)) {
+            // The `proxyAllowance` for MultiAssetData is the total units of the entire `assetData` that the proxies have been approved to spend by the `userAddress`.
+            for (const [index, nestedAssetDataElement] of decodedAssetData.nestedAssetData.entries()) {
+                const nestedAmountElement = decodedAssetData.amounts[index];
+                const nestedAssetAllowance = (await this.getProxyAllowanceAsync(
                     nestedAssetDataElement,
-                ] of (decodedAssetData as MultiAssetData).nestedAssetData.entries()) {
-                    const nestedAmountElement = (decodedAssetData as MultiAssetData).amounts[index];
-                    const nestedAssetAllowance = (await this.getProxyAllowanceAsync(
-                        nestedAssetDataElement,
-                        userAddress,
-                    )).dividedToIntegerBy(nestedAmountElement);
-                    if (_.isUndefined(proxyAllowance) || nestedAssetAllowance.lessThan(proxyAllowance)) {
-                        proxyAllowance = nestedAssetAllowance;
-                    }
+                    userAddress,
+                )).dividedToIntegerBy(nestedAmountElement);
+                if (_.isUndefined(proxyAllowance) || nestedAssetAllowance.lessThan(proxyAllowance)) {
+                    proxyAllowance = nestedAssetAllowance;
                 }
-                break;
-            default:
-                throw new Error(`Proxy with id ${decodedAssetData.assetProxyId} not supported`);
+            }
         }
         return proxyAllowance as BigNumber;
     }
diff --git a/packages/fill-scenarios/src/fill_scenarios.ts b/packages/fill-scenarios/src/fill_scenarios.ts
index 2e87e60cc..ce1f7f9ff 100644
--- a/packages/fill-scenarios/src/fill_scenarios.ts
+++ b/packages/fill-scenarios/src/fill_scenarios.ts
@@ -2,14 +2,7 @@ import { DummyERC20TokenContract, DummyERC721TokenContract, ExchangeContract } f
 import * as artifacts from '@0x/contract-artifacts';
 import { assetDataUtils } from '@0x/order-utils';
 import { orderFactory } from '@0x/order-utils/lib/src/order_factory';
-import {
-    AssetProxyId,
-    ERC20AssetData,
-    ERC721AssetData,
-    MultiAssetData,
-    OrderWithoutExchangeAddress,
-    SignedOrder,
-} from '@0x/types';
+import { OrderWithoutExchangeAddress, SignedOrder } from '@0x/types';
 import { BigNumber } from '@0x/utils';
 import { Web3Wrapper } from '@0x/web3-wrapper';
 import { Provider } from 'ethereum-types';
@@ -280,42 +273,24 @@ export class FillScenarios {
         amount: BigNumber,
     ): Promise<void> {
         const decodedAssetData = assetDataUtils.decodeAssetDataOrThrow(assetData);
-        switch (decodedAssetData.assetProxyId) {
-            case AssetProxyId.ERC20:
-                await this._increaseERC20BalanceAndAllowanceAsync(
-                    // tslint:disable-next-line:no-unnecessary-type-assertion
-                    (decodedAssetData as ERC20AssetData).tokenAddress,
-                    userAddress,
-                    amount,
-                );
-                break;
-            case AssetProxyId.ERC721:
-                await this._increaseERC721BalanceAndAllowanceAsync(
-                    // tslint:disable-next-line:no-unnecessary-type-assertion
-                    (decodedAssetData as ERC721AssetData).tokenAddress,
+        if (assetDataUtils.isERC20AssetData(decodedAssetData)) {
+            await this._increaseERC20BalanceAndAllowanceAsync(decodedAssetData.tokenAddress, userAddress, amount);
+        } else if (assetDataUtils.isERC721AssetData(decodedAssetData)) {
+            await this._increaseERC721BalanceAndAllowanceAsync(
+                decodedAssetData.tokenAddress,
+                userAddress,
+                decodedAssetData.tokenId,
+            );
+        } else if (assetDataUtils.isMultiAssetData(decodedAssetData)) {
+            for (const [index, nestedAssetDataElement] of decodedAssetData.nestedAssetData.entries()) {
+                const amountsElement = decodedAssetData.amounts[index];
+                const totalAmount = amount.times(amountsElement);
+                await this._increaseBalanceAndAllowanceWithAssetDataAsync(
+                    nestedAssetDataElement,
                     userAddress,
-                    // tslint:disable-next-line:no-unnecessary-type-assertion
-                    (decodedAssetData as ERC721AssetData).tokenId,
+                    totalAmount,
                 );
-                break;
-            case AssetProxyId.MultiAsset:
-                for (const [
-                    index,
-                    nestedAssetDataElement,
-                    // tslint:disable-next-line:no-unnecessary-type-assertion
-                ] of (decodedAssetData as MultiAssetData).nestedAssetData.entries()) {
-                    // tslint:disable-next-line:no-unnecessary-type-assertion
-                    const amountsElement = (decodedAssetData as MultiAssetData).amounts[index];
-                    const totalAmount = amount.times(amountsElement);
-                    await this._increaseBalanceAndAllowanceWithAssetDataAsync(
-                        nestedAssetDataElement,
-                        userAddress,
-                        totalAmount,
-                    );
-                }
-                break;
-            default:
-                throw new Error(`Proxy with id ${decodedAssetData.assetProxyId} not supported`);
+            }
         }
     }
 }
diff --git a/packages/order-utils/src/asset_data_utils.ts b/packages/order-utils/src/asset_data_utils.ts
index c2929d426..0526c3d00 100644
--- a/packages/order-utils/src/asset_data_utils.ts
+++ b/packages/order-utils/src/asset_data_utils.ts
@@ -7,7 +7,6 @@ import {
     SingleAssetData,
 } from '@0x/types';
 import { AbiEncoder, BigNumber } from '@0x/utils';
-import { MethodAbi } from 'ethereum-types';
 import * as _ from 'lodash';
 
 import { constants } from './constants';
@@ -23,7 +22,7 @@ export const assetDataUtils = {
      * @return The hex encoded assetData string
      */
     encodeERC20AssetData(tokenAddress: string): string {
-        const abiEncoder = new AbiEncoder.Method(constants.ERC20_METHOD_ABI as MethodAbi);
+        const abiEncoder = new AbiEncoder.Method(constants.ERC20_METHOD_ABI);
         const args = [tokenAddress];
         const assetData = abiEncoder.encode(args, encodingRules);
         return assetData;
@@ -36,7 +35,7 @@ export const assetDataUtils = {
     decodeERC20AssetData(assetData: string): ERC20AssetData {
         assetDataUtils.assertIsERC20AssetData(assetData);
         const assetProxyId = assetDataUtils.decodeAssetProxyId(assetData);
-        const abiEncoder = new AbiEncoder.Method(constants.ERC20_METHOD_ABI as MethodAbi);
+        const abiEncoder = new AbiEncoder.Method(constants.ERC20_METHOD_ABI);
         const decodedAssetData = abiEncoder.decode(assetData, decodingRules);
         return {
             assetProxyId,
@@ -52,7 +51,7 @@ export const assetDataUtils = {
      * @return The hex encoded assetData string
      */
     encodeERC721AssetData(tokenAddress: string, tokenId: BigNumber): string {
-        const abiEncoder = new AbiEncoder.Method(constants.ERC721_METHOD_ABI as MethodAbi);
+        const abiEncoder = new AbiEncoder.Method(constants.ERC721_METHOD_ABI);
         const args = [tokenAddress, tokenId];
         const assetData = abiEncoder.encode(args, encodingRules);
         return assetData;
@@ -65,7 +64,7 @@ export const assetDataUtils = {
     decodeERC721AssetData(assetData: string): ERC721AssetData {
         assetDataUtils.assertIsERC721AssetData(assetData);
         const assetProxyId = assetDataUtils.decodeAssetProxyId(assetData);
-        const abiEncoder = new AbiEncoder.Method(constants.ERC721_METHOD_ABI as MethodAbi);
+        const abiEncoder = new AbiEncoder.Method(constants.ERC721_METHOD_ABI);
         const decodedAssetData = abiEncoder.decode(assetData, decodingRules);
         return {
             assetProxyId,
@@ -90,7 +89,7 @@ export const assetDataUtils = {
             );
         }
         _.forEach(nestedAssetData, assetDataElement => assetDataUtils.validateAssetDataOrThrow(assetDataElement));
-        const abiEncoder = new AbiEncoder.Method(constants.MULTI_ASSET_METHOD_ABI as MethodAbi);
+        const abiEncoder = new AbiEncoder.Method(constants.MULTI_ASSET_METHOD_ABI);
         const args = [amounts, nestedAssetData];
         const assetData = abiEncoder.encode(args, encodingRules);
         return assetData;
@@ -103,7 +102,7 @@ export const assetDataUtils = {
     decodeMultiAssetData(assetData: string): MultiAssetData {
         assetDataUtils.assertIsMultiAssetData(assetData);
         const assetProxyId = assetDataUtils.decodeAssetProxyId(assetData);
-        const abiEncoder = new AbiEncoder.Method(constants.MULTI_ASSET_METHOD_ABI as MethodAbi);
+        const abiEncoder = new AbiEncoder.Method(constants.MULTI_ASSET_METHOD_ABI);
         const decodedAssetData = abiEncoder.decode(assetData, decodingRules);
         // TODO(abandeali1): fix return types for `AbiEncoder.Method.decode` so that we can remove type assertion
         const amounts = (decodedAssetData as any).amounts;
@@ -138,7 +137,7 @@ export const assetDataUtils = {
                         nestedAssetDataElement,
                     );
                     amounts.push(
-                        _.map(recursivelyDecodedAssetData.amounts as BigNumber[], amountElement =>
+                        _.map(recursivelyDecodedAssetData.amounts, amountElement =>
                             amountElement.times(decodedAssetData.amounts[index]),
                         ),
                     );
@@ -182,6 +181,27 @@ export const assetDataUtils = {
         return assetProxyId;
     },
     /**
+     * Checks if the decoded asset data is valid ERC20 data
+     * @param decodedAssetData The decoded asset data to check
+     */
+    isERC20AssetData(decodedAssetData: SingleAssetData | MultiAssetData): decodedAssetData is ERC20AssetData {
+        return decodedAssetData.assetProxyId === AssetProxyId.ERC20;
+    },
+    /**
+     * Checks if the decoded asset data is valid ERC721 data
+     * @param decodedAssetData The decoded asset data to check
+     */
+    isERC721AssetData(decodedAssetData: SingleAssetData | MultiAssetData): decodedAssetData is ERC721AssetData {
+        return decodedAssetData.assetProxyId === AssetProxyId.ERC721;
+    },
+    /**
+     * Checks if the decoded asset data is valid MultiAsset data
+     * @param decodedAssetData The decoded asset data to check
+     */
+    isMultiAssetData(decodedAssetData: SingleAssetData | MultiAssetData): decodedAssetData is MultiAssetData {
+        return decodedAssetData.assetProxyId === AssetProxyId.MultiAsset;
+    },
+    /**
      * Throws if the length or assetProxyId are invalid for the ERC20Proxy.
      * @param assetData Hex encoded assetData string
      */
diff --git a/packages/order-utils/src/constants.ts b/packages/order-utils/src/constants.ts
index 1248a5576..a9a687719 100644
--- a/packages/order-utils/src/constants.ts
+++ b/packages/order-utils/src/constants.ts
@@ -1,4 +1,58 @@
 import { BigNumber } from '@0x/utils';
+import { MethodAbi } from 'ethereum-types';
+
+const ERC20_METHOD_ABI: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'tokenContract',
+            type: 'address',
+        },
+    ],
+    name: 'ERC20Token',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+const ERC721_METHOD_ABI: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'tokenContract',
+            type: 'address',
+        },
+        {
+            name: 'tokenId',
+            type: 'uint256',
+        },
+    ],
+    name: 'ERC721Token',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+const MULTI_ASSET_METHOD_ABI: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'amounts',
+            type: 'uint256[]',
+        },
+        {
+            name: 'nestedAssetData',
+            type: 'bytes[]',
+        },
+    ],
+    name: 'MultiAsset',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
 
 export const constants = {
     NULL_ADDRESS: '0x0000000000000000000000000000000000000000',
@@ -49,54 +103,7 @@ export const constants = {
             { name: 'data', type: 'bytes' },
         ],
     },
-    ERC20_METHOD_ABI: {
-        constant: false,
-        inputs: [
-            {
-                name: 'tokenContract',
-                type: 'address',
-            },
-        ],
-        name: 'ERC20Token',
-        outputs: [],
-        payable: false,
-        stateMutability: 'nonpayable',
-        type: 'function',
-    },
-    ERC721_METHOD_ABI: {
-        constant: false,
-        inputs: [
-            {
-                name: 'tokenContract',
-                type: 'address',
-            },
-            {
-                name: 'tokenId',
-                type: 'uint256',
-            },
-        ],
-        name: 'ERC721Token',
-        outputs: [],
-        payable: false,
-        stateMutability: 'nonpayable',
-        type: 'function',
-    },
-    MULTI_ASSET_METHOD_ABI: {
-        constant: false,
-        inputs: [
-            {
-                name: 'amounts',
-                type: 'uint256[]',
-            },
-            {
-                name: 'nestedAssetData',
-                type: 'bytes[]',
-            },
-        ],
-        name: 'MultiAsset',
-        outputs: [],
-        payable: false,
-        stateMutability: 'nonpayable',
-        type: 'function',
-    },
+    ERC20_METHOD_ABI,
+    ERC721_METHOD_ABI,
+    MULTI_ASSET_METHOD_ABI,
 };
diff --git a/packages/order-utils/src/exchange_transfer_simulator.ts b/packages/order-utils/src/exchange_transfer_simulator.ts
index 0a948fd1f..06621fd9e 100644
--- a/packages/order-utils/src/exchange_transfer_simulator.ts
+++ b/packages/order-utils/src/exchange_transfer_simulator.ts
@@ -108,7 +108,7 @@ export class ExchangeTransferSimulator {
                     const amountsElement = decodedAssetData.amounts[index];
                     const totalAmount = amountInBaseUnits.times(amountsElement);
                     await this.transferFromAsync(
-                        nestedAssetDataElement as string,
+                        nestedAssetDataElement,
                         from,
                         to,
                         totalAmount,
diff --git a/packages/order-utils/src/order_state_utils.ts b/packages/order-utils/src/order_state_utils.ts
index 9e3e228ba..389419587 100644
--- a/packages/order-utils/src/order_state_utils.ts
+++ b/packages/order-utils/src/order_state_utils.ts
@@ -1,14 +1,11 @@
 import {
-    AssetProxyId,
     ExchangeContractErrs,
-    MultiAssetData,
     ObjectMap,
     OrderRelevantState,
     OrderState,
     OrderStateInvalid,
     OrderStateValid,
     SignedOrder,
-    SingleAssetData,
 } from '@0x/types';
 import { BigNumber } from '@0x/utils';
 import * as _ from 'lodash';
@@ -310,22 +307,16 @@ export class OrderStateUtils {
     ): Promise<ObjectMap<BigNumber>> {
         const decodedAssetData = assetDataUtils.decodeAssetDataOrThrow(assetData);
         let balances: ObjectMap<BigNumber> = { ...initialBalances };
-        switch (decodedAssetData.assetProxyId) {
-            case AssetProxyId.ERC20:
-            case AssetProxyId.ERC721:
-                const balance = await this._balanceAndProxyAllowanceFetcher.getBalanceAsync(assetData, traderAddress);
-                const tokenAddress = (decodedAssetData as SingleAssetData).tokenAddress;
-                balances[tokenAddress] = _.isUndefined(initialBalances[tokenAddress])
-                    ? balance
-                    : balances[tokenAddress].add(balance);
-                break;
-            case AssetProxyId.MultiAsset:
-                for (const assetDataElement of (decodedAssetData as MultiAssetData).nestedAssetData) {
-                    balances = await this._getAssetBalancesAsync(assetDataElement, traderAddress, balances);
-                }
-                break;
-            default:
-                throw new Error(`Proxy with id ${decodedAssetData.assetProxyId} not supported`);
+        if (assetDataUtils.isERC20AssetData(decodedAssetData) || assetDataUtils.isERC721AssetData(decodedAssetData)) {
+            const balance = await this._balanceAndProxyAllowanceFetcher.getBalanceAsync(assetData, traderAddress);
+            const tokenAddress = decodedAssetData.tokenAddress;
+            balances[tokenAddress] = _.isUndefined(initialBalances[tokenAddress])
+                ? balance
+                : balances[tokenAddress].add(balance);
+        } else if (assetDataUtils.isMultiAssetData(decodedAssetData)) {
+            for (const assetDataElement of decodedAssetData.nestedAssetData) {
+                balances = await this._getAssetBalancesAsync(assetDataElement, traderAddress, balances);
+            }
         }
         return balances;
     }
@@ -336,25 +327,19 @@ export class OrderStateUtils {
     ): Promise<ObjectMap<BigNumber>> {
         const decodedAssetData = assetDataUtils.decodeAssetDataOrThrow(assetData);
         let allowances: ObjectMap<BigNumber> = { ...initialAllowances };
-        switch (decodedAssetData.assetProxyId) {
-            case AssetProxyId.ERC20:
-            case AssetProxyId.ERC721:
-                const allowance = await this._balanceAndProxyAllowanceFetcher.getProxyAllowanceAsync(
-                    assetData,
-                    traderAddress,
-                );
-                const tokenAddress = (decodedAssetData as SingleAssetData).tokenAddress;
-                allowances[tokenAddress] = _.isUndefined(initialAllowances[tokenAddress])
-                    ? allowance
-                    : allowances[tokenAddress].add(allowance);
-                break;
-            case AssetProxyId.MultiAsset:
-                for (const assetDataElement of (decodedAssetData as MultiAssetData).nestedAssetData) {
-                    allowances = await this._getAssetBalancesAsync(assetDataElement, traderAddress, allowances);
-                }
-                break;
-            default:
-                throw new Error(`Proxy with id ${decodedAssetData.assetProxyId} not supported`);
+        if (assetDataUtils.isERC20AssetData(decodedAssetData) || assetDataUtils.isERC721AssetData(decodedAssetData)) {
+            const allowance = await this._balanceAndProxyAllowanceFetcher.getProxyAllowanceAsync(
+                assetData,
+                traderAddress,
+            );
+            const tokenAddress = decodedAssetData.tokenAddress;
+            allowances[tokenAddress] = _.isUndefined(initialAllowances[tokenAddress])
+                ? allowance
+                : allowances[tokenAddress].add(allowance);
+        } else if (assetDataUtils.isMultiAssetData(decodedAssetData)) {
+            for (const assetDataElement of decodedAssetData.nestedAssetData) {
+                allowances = await this._getAssetBalancesAsync(assetDataElement, traderAddress, allowances);
+            }
         }
         return allowances;
     }
diff --git a/packages/order-utils/test/asset_data_utils_test.ts b/packages/order-utils/test/asset_data_utils_test.ts
index ebc5bdeac..c498c5a00 100644
--- a/packages/order-utils/test/asset_data_utils_test.ts
+++ b/packages/order-utils/test/asset_data_utils_test.ts
@@ -27,7 +27,6 @@ const KNOWN_MULTI_ASSET_ENCODING = {
         '0x94cfcdd7000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000024f47261b00000000000000000000000001dc4c1cefef38a777b15aa20260a54e584b16c48000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000044025717920000000000000000000000001dc4c1cefef38a777b15aa20260a54e584b16c48000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000',
 };
 
-// tslint:disable:no-unnecessary-type-assertion
 describe('assetDataUtils', () => {
     it('should encode ERC20', () => {
         const assetData = assetDataUtils.encodeERC20AssetData(KNOWN_ERC20_ENCODING.address);
@@ -69,6 +68,7 @@ describe('assetDataUtils', () => {
         expect(decodedAssetData.assetProxyId).to.equal(AssetProxyId.MultiAsset);
         expect(decodedAssetData.amounts).to.deep.equal(KNOWN_MULTI_ASSET_ENCODING.amounts);
         const decodedErc20AssetData = decodedAssetData.nestedAssetData[0];
+        // tslint:disable-next-line:no-unnecessary-type-assertion
         const decodedErc721AssetData = decodedAssetData.nestedAssetData[1] as ERC721AssetData;
         expect(decodedErc20AssetData.tokenAddress).to.equal(KNOWN_ERC20_ENCODING.address);
         expect(decodedErc20AssetData.assetProxyId).to.equal(AssetProxyId.ERC20);
@@ -91,8 +91,10 @@ describe('assetDataUtils', () => {
         const expectedLength = 4;
         expect(decodedAssetData.nestedAssetData.length).to.be.equal(expectedLength);
         const decodedErc20AssetData1 = decodedAssetData.nestedAssetData[0];
+        // tslint:disable-next-line:no-unnecessary-type-assertion
         const decodedErc721AssetData1 = decodedAssetData.nestedAssetData[1] as ERC721AssetData;
         const decodedErc20AssetData2 = decodedAssetData.nestedAssetData[2];
+        // tslint:disable-next-line:no-unnecessary-type-assertion
         const decodedErc721AssetData2 = decodedAssetData.nestedAssetData[3] as ERC721AssetData;
         expect(decodedErc20AssetData1.tokenAddress).to.equal(KNOWN_ERC20_ENCODING.address);
         expect(decodedErc20AssetData1.assetProxyId).to.equal(AssetProxyId.ERC20);
diff --git a/packages/order-watcher/src/order_watcher/dependent_order_hashes_tracker.ts b/packages/order-watcher/src/order_watcher/dependent_order_hashes_tracker.ts
index 12723f73e..d1085014c 100644
--- a/packages/order-watcher/src/order_watcher/dependent_order_hashes_tracker.ts
+++ b/packages/order-watcher/src/order_watcher/dependent_order_hashes_tracker.ts
@@ -1,6 +1,5 @@
-// tslint:disable:no-unnecessary-type-assertion
 import { assetDataUtils, orderHashUtils } from '@0x/order-utils';
-import { AssetProxyId, ERC20AssetData, ERC721AssetData, MultiAssetData, SignedOrder } from '@0x/types';
+import { AssetProxyId, SignedOrder } from '@0x/types';
 import { BigNumber } from '@0x/utils';
 import * as _ from 'lodash';
 
@@ -70,7 +69,10 @@ export class DependentOrderHashesTracker {
         this._removeAssetDataFromDependentOrderHashes(signedOrder, signedOrder.makerAssetData);
         // If makerToken === ZRX then we already removed it and we don't need to remove it again.
         const decodedMakerAssetData = assetDataUtils.decodeAssetDataOrThrow(signedOrder.makerAssetData);
-        if ((decodedMakerAssetData as ERC20AssetData).tokenAddress !== this._zrxTokenAddress) {
+        if (
+            assetDataUtils.isERC20AssetData(decodedMakerAssetData) &&
+            decodedMakerAssetData.tokenAddress !== this._zrxTokenAddress
+        ) {
             this._removeFromERC20DependentOrderhashes(signedOrder, this._zrxTokenAddress);
         }
         this._removeFromMakerDependentOrderhashes(signedOrder);
@@ -149,24 +151,14 @@ export class DependentOrderHashesTracker {
     }
     private _addAssetDataToDependentOrderHashes(signedOrder: SignedOrder, assetData: string): void {
         const decodedAssetData = assetDataUtils.decodeAssetDataOrThrow(assetData);
-        switch (decodedAssetData.assetProxyId) {
-            case AssetProxyId.ERC20:
-                this._addToERC20DependentOrderHashes(signedOrder, (decodedAssetData as ERC20AssetData).tokenAddress);
-                break;
-            case AssetProxyId.ERC721:
-                this._addToERC721DependentOrderHashes(
-                    signedOrder,
-                    (decodedAssetData as ERC721AssetData).tokenAddress,
-                    (decodedAssetData as ERC721AssetData).tokenId,
-                );
-                break;
-            case AssetProxyId.MultiAsset:
-                _.each((decodedAssetData as MultiAssetData).nestedAssetData, nestedAssetDataElement =>
-                    this._addAssetDataToDependentOrderHashes(signedOrder, nestedAssetDataElement),
-                );
-                break;
-            default:
-                break;
+        if (assetDataUtils.isERC20AssetData(decodedAssetData)) {
+            this._addToERC20DependentOrderHashes(signedOrder, decodedAssetData.tokenAddress);
+        } else if (assetDataUtils.isERC721AssetData(decodedAssetData)) {
+            this._addToERC721DependentOrderHashes(signedOrder, decodedAssetData.tokenAddress, decodedAssetData.tokenId);
+        } else if (assetDataUtils.isMultiAssetData(decodedAssetData)) {
+            _.each(decodedAssetData.nestedAssetData, nestedAssetDataElement =>
+                this._addAssetDataToDependentOrderHashes(signedOrder, nestedAssetDataElement),
+            );
         }
     }
     private _addToMakerDependentOrderHashes(signedOrder: SignedOrder): void {
@@ -234,27 +226,18 @@ export class DependentOrderHashesTracker {
     }
     private _removeAssetDataFromDependentOrderHashes(signedOrder: SignedOrder, assetData: string): void {
         const decodedAssetData = assetDataUtils.decodeAssetDataOrThrow(assetData);
-        switch (decodedAssetData.assetProxyId) {
-            case AssetProxyId.ERC20:
-                this._removeFromERC20DependentOrderhashes(
-                    signedOrder,
-                    (decodedAssetData as ERC20AssetData).tokenAddress,
-                );
-                break;
-            case AssetProxyId.ERC721:
-                this._removeFromERC721DependentOrderhashes(
-                    signedOrder,
-                    (decodedAssetData as ERC721AssetData).tokenAddress,
-                    (decodedAssetData as ERC721AssetData).tokenId,
-                );
-                break;
-            case AssetProxyId.MultiAsset:
-                _.each((decodedAssetData as MultiAssetData).nestedAssetData, nestedAssetDataElement =>
-                    this._removeAssetDataFromDependentOrderHashes(signedOrder, nestedAssetDataElement),
-                );
-                break;
-            default:
-                break;
+        if (assetDataUtils.isERC20AssetData(decodedAssetData)) {
+            this._removeFromERC20DependentOrderhashes(signedOrder, decodedAssetData.tokenAddress);
+        } else if (assetDataUtils.isERC721AssetData(decodedAssetData)) {
+            this._removeFromERC721DependentOrderhashes(
+                signedOrder,
+                decodedAssetData.tokenAddress,
+                decodedAssetData.tokenId,
+            );
+        } else if (assetDataUtils.isMultiAssetData(decodedAssetData)) {
+            _.each(decodedAssetData.nestedAssetData, nestedAssetDataElement =>
+                this._removeAssetDataFromDependentOrderHashes(signedOrder, nestedAssetDataElement),
+            );
         }
     }
 }
diff --git a/packages/order-watcher/src/order_watcher/order_watcher.ts b/packages/order-watcher/src/order_watcher/order_watcher.ts
index c48606555..656f21a53 100644
--- a/packages/order-watcher/src/order_watcher/order_watcher.ts
+++ b/packages/order-watcher/src/order_watcher/order_watcher.ts
@@ -32,16 +32,7 @@ import {
     orderHashUtils,
     OrderStateUtils,
 } from '@0x/order-utils';
-import {
-    AssetProxyId,
-    ERC20AssetData,
-    ERC721AssetData,
-    ExchangeContractErrs,
-    MultiAssetData,
-    OrderState,
-    SignedOrder,
-    Stats,
-} from '@0x/types';
+import { AssetProxyId, ExchangeContractErrs, OrderState, SignedOrder, Stats } from '@0x/types';
 import { errorUtils, intervalUtils } from '@0x/utils';
 import { BlockParamLiteral, LogEntryEvent, LogWithDecodedArgs, Provider } from 'ethereum-types';
 import * as _ from 'lodash';
@@ -240,20 +231,14 @@ export class OrderWatcher {
     }
     private _addAssetDataToAbiDecoder(assetData: string): void {
         const decodedAssetData = assetDataUtils.decodeAssetDataOrThrow(assetData);
-        switch (decodedAssetData.assetProxyId) {
-            case AssetProxyId.ERC20:
-                this._collisionResistantAbiDecoder.addERC20Token((decodedAssetData as ERC20AssetData).tokenAddress);
-                break;
-            case AssetProxyId.ERC721:
-                this._collisionResistantAbiDecoder.addERC721Token((decodedAssetData as ERC721AssetData).tokenAddress);
-                break;
-            case AssetProxyId.MultiAsset:
-                _.each((decodedAssetData as MultiAssetData).nestedAssetData, nestedAssetDataElement =>
-                    this._addAssetDataToAbiDecoder(nestedAssetDataElement),
-                );
-                break;
-            default:
-                break;
+        if (assetDataUtils.isERC20AssetData(decodedAssetData)) {
+            this._collisionResistantAbiDecoder.addERC20Token(decodedAssetData.tokenAddress);
+        } else if (assetDataUtils.isERC721AssetData(decodedAssetData)) {
+            this._collisionResistantAbiDecoder.addERC721Token(decodedAssetData.tokenAddress);
+        } else if (assetDataUtils.isMultiAssetData(decodedAssetData)) {
+            _.each(decodedAssetData.nestedAssetData, nestedAssetDataElement =>
+                this._addAssetDataToAbiDecoder(nestedAssetDataElement),
+            );
         }
     }
     private _deleteLazyStoreBalance(assetData: string, userAddress: string): void {
diff --git a/packages/pipeline/src/parsers/events/exchange_events.ts b/packages/pipeline/src/parsers/events/exchange_events.ts
index 8d2e7dec7..9c4a5f89a 100644
--- a/packages/pipeline/src/parsers/events/exchange_events.ts
+++ b/packages/pipeline/src/parsers/events/exchange_events.ts
@@ -1,14 +1,12 @@
 import { ExchangeCancelEventArgs, ExchangeCancelUpToEventArgs, ExchangeFillEventArgs } from '@0x/contract-wrappers';
 import { assetDataUtils } from '@0x/order-utils';
-import { AssetProxyId, ERC721AssetData, SingleAssetData } from '@0x/types';
+import { AssetProxyId, ERC721AssetData } from '@0x/types';
 import { LogWithDecodedArgs } from 'ethereum-types';
 import * as R from 'ramda';
 
 import { ExchangeCancelEvent, ExchangeCancelUpToEvent, ExchangeFillEvent } from '../../entities';
 import { bigNumbertoStringOrNull, convertAssetProxyIdToType } from '../../utils';
 
-// tslint:disable:no-unnecessary-type-assertion
-
 /**
  * Parses raw event logs for a fill event and returns an array of
  * ExchangeFillEvent entities.
@@ -59,26 +57,24 @@ export function _convertToExchangeFillEvent(eventLog: LogWithDecodedArgs<Exchang
     exchangeFillEvent.takerFeePaid = eventLog.args.takerFeePaid;
     exchangeFillEvent.orderHash = eventLog.args.orderHash;
     exchangeFillEvent.rawMakerAssetData = eventLog.args.makerAssetData;
+    // tslint:disable-next-line:no-unnecessary-type-assertion
     exchangeFillEvent.makerAssetType = convertAssetProxyIdToType(makerAssetData.assetProxyId as AssetProxyId);
     exchangeFillEvent.makerAssetProxyId = makerAssetData.assetProxyId;
-    // HACK(abandeali1): this event schema currently does not support multiple maker/taker assets, so we store a null byte array when decoding assetData from the MultiAssetProxy
-    exchangeFillEvent.makerTokenAddress =
-        makerAssetData.assetProxyId === AssetProxyId.MultiAsset
-            ? assetDataUtils.decodeMultiAssetDataRecursively(eventLog.args.makerAssetData).nestedAssetData[0]
-                  .tokenAddress
-            : (makerAssetData as SingleAssetData).tokenAddress;
+    // HACK(abandeali1): this event schema currently does not support multiple maker/taker assets, so we store the first token address from the MultiAssetProxy assetData
+    exchangeFillEvent.makerTokenAddress = assetDataUtils.isMultiAssetData(makerAssetData)
+        ? assetDataUtils.decodeMultiAssetDataRecursively(eventLog.args.makerAssetData).nestedAssetData[0].tokenAddress
+        : makerAssetData.tokenAddress;
     // tslint has a false positive here. Type assertion is required.
     // tslint:disable-next-line:no-unnecessary-type-assertion
     exchangeFillEvent.makerTokenId = bigNumbertoStringOrNull((makerAssetData as ERC721AssetData).tokenId);
     exchangeFillEvent.rawTakerAssetData = eventLog.args.takerAssetData;
+    // tslint:disable-next-line:no-unnecessary-type-assertion
     exchangeFillEvent.takerAssetType = convertAssetProxyIdToType(takerAssetData.assetProxyId as AssetProxyId);
     exchangeFillEvent.takerAssetProxyId = takerAssetData.assetProxyId;
-    // HACK(abandeali1): this event schema currently does not support multiple maker/taker assets, so we store a null byte array when decoding assetData from the MultiAssetProxy
-    exchangeFillEvent.takerTokenAddress =
-        takerAssetData.assetProxyId === AssetProxyId.MultiAsset
-            ? assetDataUtils.decodeMultiAssetDataRecursively(eventLog.args.takerAssetData).nestedAssetData[0]
-                  .tokenAddress
-            : (takerAssetData as SingleAssetData).tokenAddress;
+    // HACK(abandeali1): this event schema currently does not support multiple maker/taker assets, so we store the first token address from the MultiAssetProxy assetData
+    exchangeFillEvent.takerTokenAddress = assetDataUtils.isMultiAssetData(takerAssetData)
+        ? assetDataUtils.decodeMultiAssetDataRecursively(eventLog.args.takerAssetData).nestedAssetData[0].tokenAddress
+        : takerAssetData.tokenAddress;
     // tslint:disable-next-line:no-unnecessary-type-assertion
     exchangeFillEvent.takerTokenId = bigNumbertoStringOrNull((takerAssetData as ERC721AssetData).tokenId);
     return exchangeFillEvent;
@@ -106,25 +102,23 @@ export function _convertToExchangeCancelEvent(
     exchangeCancelEvent.senderAddress = eventLog.args.senderAddress;
     exchangeCancelEvent.orderHash = eventLog.args.orderHash;
     exchangeCancelEvent.rawMakerAssetData = eventLog.args.makerAssetData;
+    // tslint:disable-next-line:no-unnecessary-type-assertion
     exchangeCancelEvent.makerAssetType = convertAssetProxyIdToType(makerAssetData.assetProxyId as AssetProxyId);
     exchangeCancelEvent.makerAssetProxyId = makerAssetData.assetProxyId;
-    // HACK(abandeali1): this event schema currently does not support multiple maker/taker assets, so we store a null byte array when decoding assetData from the MultiAssetProxy
-    exchangeCancelEvent.makerTokenAddress =
-        makerAssetData.assetProxyId === AssetProxyId.MultiAsset
-            ? assetDataUtils.decodeMultiAssetDataRecursively(eventLog.args.makerAssetData).nestedAssetData[0]
-                  .tokenAddress
-            : (makerAssetData as SingleAssetData).tokenAddress;
+    // HACK(abandeali1): this event schema currently does not support multiple maker/taker assets, so we store the first token address from the MultiAssetProxy assetData
+    exchangeCancelEvent.makerTokenAddress = assetDataUtils.isMultiAssetData(makerAssetData)
+        ? assetDataUtils.decodeMultiAssetDataRecursively(eventLog.args.makerAssetData).nestedAssetData[0].tokenAddress
+        : makerAssetData.tokenAddress;
     // tslint:disable-next-line:no-unnecessary-type-assertion
     exchangeCancelEvent.makerTokenId = bigNumbertoStringOrNull((makerAssetData as ERC721AssetData).tokenId);
     exchangeCancelEvent.rawTakerAssetData = eventLog.args.takerAssetData;
+    // tslint:disable-next-line:no-unnecessary-type-assertion
     exchangeCancelEvent.takerAssetType = convertAssetProxyIdToType(takerAssetData.assetProxyId as AssetProxyId);
     exchangeCancelEvent.takerAssetProxyId = takerAssetData.assetProxyId;
-    // HACK(abandeali1): this event schema currently does not support multiple maker/taker assets, so we store a null byte array when decoding assetData from the MultiAssetProxy
-    exchangeCancelEvent.takerTokenAddress =
-        takerAssetData.assetProxyId === AssetProxyId.MultiAsset
-            ? assetDataUtils.decodeMultiAssetDataRecursively(eventLog.args.takerAssetData).nestedAssetData[0]
-                  .tokenAddress
-            : (takerAssetData as SingleAssetData).tokenAddress;
+    // HACK(abandeali1): this event schema currently does not support multiple maker/taker assets, so we store the first token address from the MultiAssetProxy assetData
+    exchangeCancelEvent.takerTokenAddress = assetDataUtils.isMultiAssetData(takerAssetData)
+        ? assetDataUtils.decodeMultiAssetDataRecursively(eventLog.args.takerAssetData).nestedAssetData[0].tokenAddress
+        : takerAssetData.tokenAddress;
     // tslint:disable-next-line:no-unnecessary-type-assertion
     exchangeCancelEvent.takerTokenId = bigNumbertoStringOrNull((takerAssetData as ERC721AssetData).tokenId);
     return exchangeCancelEvent;
diff --git a/packages/pipeline/src/parsers/sra_orders/index.ts b/packages/pipeline/src/parsers/sra_orders/index.ts
index 10546921d..13fe632a4 100644
--- a/packages/pipeline/src/parsers/sra_orders/index.ts
+++ b/packages/pipeline/src/parsers/sra_orders/index.ts
@@ -1,13 +1,11 @@
 import { APIOrder, OrdersResponse } from '@0x/connect';
 import { assetDataUtils, orderHashUtils } from '@0x/order-utils';
-import { AssetProxyId, ERC721AssetData, SingleAssetData } from '@0x/types';
+import { AssetProxyId, ERC721AssetData } from '@0x/types';
 import * as R from 'ramda';
 
 import { SraOrder } from '../../entities';
 import { bigNumbertoStringOrNull, convertAssetProxyIdToType } from '../../utils';
 
-// tslint:disable:no-unnecessary-type-assertion
-
 /**
  * Parses a raw order response from an SRA endpoint and returns an array of
  * SraOrder entities.
@@ -43,26 +41,24 @@ export function _convertToEntity(apiOrder: APIOrder): SraOrder {
     sraOrder.signature = apiOrder.order.signature;
 
     sraOrder.rawMakerAssetData = apiOrder.order.makerAssetData;
+    // tslint:disable-next-line:no-unnecessary-type-assertion
     sraOrder.makerAssetType = convertAssetProxyIdToType(makerAssetData.assetProxyId as AssetProxyId);
     sraOrder.makerAssetProxyId = makerAssetData.assetProxyId;
-    // HACK(abandeali1): this event schema currently does not support multiple maker/taker assets, so we store a null byte array when decoding assetData from the MultiAssetProxy
-    sraOrder.makerTokenAddress =
-        makerAssetData.assetProxyId === AssetProxyId.MultiAsset
-            ? assetDataUtils.decodeMultiAssetDataRecursively(apiOrder.order.makerAssetData).nestedAssetData[0]
-                  .tokenAddress
-            : (makerAssetData as SingleAssetData).tokenAddress;
+    // HACK(abandeali1): this event schema currently does not support multiple maker/taker assets, so we store the first token address from the MultiAssetProxy assetData
+    sraOrder.makerTokenAddress = assetDataUtils.isMultiAssetData(makerAssetData)
+        ? assetDataUtils.decodeMultiAssetDataRecursively(apiOrder.order.makerAssetData).nestedAssetData[0].tokenAddress
+        : makerAssetData.tokenAddress;
     // tslint has a false positive here. Type assertion is required.
     // tslint:disable-next-line:no-unnecessary-type-assertion
     sraOrder.makerTokenId = bigNumbertoStringOrNull((makerAssetData as ERC721AssetData).tokenId);
     sraOrder.rawTakerAssetData = apiOrder.order.takerAssetData;
+    // tslint:disable-next-line:no-unnecessary-type-assertion
     sraOrder.takerAssetType = convertAssetProxyIdToType(takerAssetData.assetProxyId as AssetProxyId);
     sraOrder.takerAssetProxyId = takerAssetData.assetProxyId;
-    // HACK(abandeali1): this event schema currently does not support multiple maker/taker assets, so we store a null byte array when decoding assetData from the MultiAssetProxy
-    sraOrder.takerTokenAddress =
-        takerAssetData.assetProxyId === AssetProxyId.MultiAsset
-            ? assetDataUtils.decodeMultiAssetDataRecursively(apiOrder.order.takerAssetData).nestedAssetData[0]
-                  .tokenAddress
-            : (takerAssetData as SingleAssetData).tokenAddress;
+    // HACK(abandeali1): this event schema currently does not support multiple maker/taker assets, so we store the first token address from the MultiAssetProxy assetData
+    sraOrder.takerTokenAddress = assetDataUtils.isMultiAssetData(takerAssetData)
+        ? assetDataUtils.decodeMultiAssetDataRecursively(apiOrder.order.takerAssetData).nestedAssetData[0].tokenAddress
+        : takerAssetData.tokenAddress;
     // tslint:disable-next-line:no-unnecessary-type-assertion
     sraOrder.takerTokenId = bigNumbertoStringOrNull((takerAssetData as ERC721AssetData).tokenId);
 
diff --git a/yarn.lock b/yarn.lock
index 62a48e0e5..b86969e3b 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2100,10 +2100,6 @@ aes-js@^0.2.3:
   version "0.2.4"
   resolved "https://registry.yarnpkg.com/aes-js/-/aes-js-0.2.4.tgz#94b881ab717286d015fa219e08fb66709dda5a3d"
 
-aes-js@^3.1.1:
-  version "3.1.2"
-  resolved "https://registry.npmjs.org/aes-js/-/aes-js-3.1.2.tgz#db9aabde85d5caabbfc0d4f2a4446960f627146a"
-
 agent-base@4, agent-base@^4.1.0, agent-base@~4.2.0:
   version "4.2.1"
   resolved "https://registry.yarnpkg.com/agent-base/-/agent-base-4.2.1.tgz#d89e5999f797875674c07d87f260fc41e83e8ca9"
@@ -3669,7 +3665,7 @@ bs-logger@0.x:
   dependencies:
     fast-json-stable-stringify "^2.0.0"
 
-bs58@=4.0.1, bs58@^4.0.0:
+bs58@=4.0.1:
   version "4.0.1"
   resolved "https://registry.yarnpkg.com/bs58/-/bs58-4.0.1.tgz#be161e76c354f6f788ae4071f63f34e8c4f0a42a"
   dependencies:
@@ -3692,14 +3688,6 @@ bs58check@^1.0.8:
     bs58 "^3.1.0"
     create-hash "^1.1.0"
 
-bs58check@^2.1.2:
-  version "2.1.2"
-  resolved "https://registry.npmjs.org/bs58check/-/bs58check-2.1.2.tgz#53b018291228d82a5aa08e7d796fdafda54aebfc"
-  dependencies:
-    bs58 "^4.0.0"
-    create-hash "^1.1.0"
-    safe-buffer "^5.1.2"
-
 bser@^2.0.0:
   version "2.0.0"
   resolved "https://registry.npmjs.org/bser/-/bser-2.0.0.tgz#9ac78d3ed5d915804fd87acb158bc797147a1719"
@@ -6410,19 +6398,6 @@ ethereumjs-wallet@0.6.0:
     utf8 "^2.1.1"
     uuid "^2.0.1"
 
-ethereumjs-wallet@~0.6.0:
-  version "0.6.2"
-  resolved "https://registry.npmjs.org/ethereumjs-wallet/-/ethereumjs-wallet-0.6.2.tgz#67244b6af3e8113b53d709124b25477b64aeccda"
-  dependencies:
-    aes-js "^3.1.1"
-    bs58check "^2.1.2"
-    ethereumjs-util "^5.2.0"
-    hdkey "^1.0.0"
-    safe-buffer "^5.1.2"
-    scrypt.js "^0.2.0"
-    utf8 "^3.0.0"
-    uuid "^3.3.2"
-
 ethers@~4.0.4:
   version "4.0.4"
   resolved "https://registry.yarnpkg.com/ethers/-/ethers-4.0.4.tgz#d3f85e8b27f4b59537e06526439b0fb15b44dc65"
@@ -8077,14 +8052,6 @@ hdkey@^0.7.0, hdkey@^0.7.1:
     coinstring "^2.0.0"
     secp256k1 "^3.0.1"
 
-hdkey@^1.0.0:
-  version "1.1.0"
-  resolved "https://registry.npmjs.org/hdkey/-/hdkey-1.1.0.tgz#e74e7b01d2c47f797fa65d1d839adb7a44639f29"
-  dependencies:
-    coinstring "^2.0.0"
-    safe-buffer "^5.1.1"
-    secp256k1 "^3.0.1"
-
 he@1.1.1:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/he/-/he-1.1.1.tgz#93410fd21b009735151f8868c2f271f3427e23fd"
@@ -16679,10 +16646,6 @@ utf8@^2.1.1:
   version "2.1.2"
   resolved "https://registry.yarnpkg.com/utf8/-/utf8-2.1.2.tgz#1fa0d9270e9be850d9b05027f63519bf46457d96"
 
-utf8@^3.0.0:
-  version "3.0.0"
-  resolved "https://registry.npmjs.org/utf8/-/utf8-3.0.0.tgz#f052eed1364d696e769ef058b183df88c87f69d1"
-
 util-deprecate@~1.0.1:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/util-deprecate/-/util-deprecate-1.0.2.tgz#450d4dc9fa70de732762fbd2d4a28981419a0ccf"