Merge branch 'development' into feature/order-watcher/dockerize

* development: (898 commits)
  Fixed merge conflict from development
  Ran prettier
  Doc generation working for changes by dutch auction wrapper
  added changelog entry for monorepo-scripts
  Hide dutch auction wrapper from docs -- hopefully this will prevent the "must export Web3Wrapper" error from doc generation
  relaxed version on contract-extension dependencies
  Added NetworkID 50 address for dutch auction wrapper
  removed manual updte of package.json version
  export dutch auction wrapper types from 0x.js
  Export dutch auction wrapper in 0x.js
  ran prettier
  Minor documentation updates to dutch auction wrapper
  `afterAuctionDetails` -> `auctionDetails`
  Added @todo for including dutch auction addresses once deployed
  Ran prettier & linter
  Removed redundant assignment
  removed needless newline on contract-wrappers changelog
  removed timestamp from changelog for abi-gen-wrappers
  added dutch auction address for testnets
  removed .only
  ...

1 files changed, 44 insertions, 30 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 d10cffe57..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
@@ -1,8 +1,7 @@
-// tslint:disable:no-unnecessary-type-assertion
 import { AbstractBalanceAndProxyAllowanceFetcher, assetDataUtils } from '@0x/order-utils';
-import { AssetProxyId, ERC20AssetData, ERC721AssetData } from '@0x/types';
 import { BigNumber } from '@0x/utils';
 import { BlockParamLiteral } from 'ethereum-types';
+import * as _ from 'lodash';
 
 import { ERC20TokenWrapper } from '../contract_wrappers/erc20_token_wrapper';
 import { ERC721TokenWrapper } from '../contract_wrappers/erc721_token_wrapper';
@@ -18,42 +17,45 @@ export class AssetBalanceAndProxyAllowanceFetcher implements AbstractBalanceAndP
     }
     public async getBalanceAsync(assetData: string, userAddress: string): Promise<BigNumber> {
         const decodedAssetData = assetDataUtils.decodeAssetDataOrThrow(assetData);
-        if (decodedAssetData.assetProxyId === AssetProxyId.ERC20) {
-            const decodedERC20AssetData = decodedAssetData as ERC20AssetData;
-            const balance = await this._erc20Token.getBalanceAsync(decodedERC20AssetData.tokenAddress, userAddress, {
+        let balance: BigNumber | undefined;
+        if (assetDataUtils.isERC20AssetData(decodedAssetData)) {
+            balance = await this._erc20Token.getBalanceAsync(decodedAssetData.tokenAddress, userAddress, {
                 defaultBlock: this._stateLayer,
             });
-            return balance;
-        } else {
-            const decodedERC721AssetData = decodedAssetData as ERC721AssetData;
+        } else if (assetDataUtils.isERC721AssetData(decodedAssetData)) {
             const tokenOwner = await this._erc721Token.getOwnerOfAsync(
-                decodedERC721AssetData.tokenAddress,
-                decodedERC721AssetData.tokenId,
+                decodedAssetData.tokenAddress,
+                decodedAssetData.tokenId,
                 {
                     defaultBlock: this._stateLayer,
                 },
             );
-            const balance = tokenOwner === userAddress ? new BigNumber(1) : new BigNumber(0);
-            return balance;
+            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,
+                    userAddress,
+                )).dividedToIntegerBy(nestedAmountElement);
+                if (_.isUndefined(balance) || nestedAssetBalance.lessThan(balance)) {
+                    balance = nestedAssetBalance;
+                }
+            }
         }
+        return balance as BigNumber;
     }
     public async getProxyAllowanceAsync(assetData: string, userAddress: string): Promise<BigNumber> {
         const decodedAssetData = assetDataUtils.decodeAssetDataOrThrow(assetData);
-        if (decodedAssetData.assetProxyId === AssetProxyId.ERC20) {
-            const decodedERC20AssetData = decodedAssetData as ERC20AssetData;
-            const proxyAllowance = await this._erc20Token.getProxyAllowanceAsync(
-                decodedERC20AssetData.tokenAddress,
-                userAddress,
-                {
-                    defaultBlock: this._stateLayer,
-                },
-            );
-            return proxyAllowance;
-        } else {
-            const decodedERC721AssetData = decodedAssetData as ERC721AssetData;
-
+        let proxyAllowance: BigNumber | undefined;
+        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(
-                decodedERC721AssetData.tokenAddress,
+                decodedAssetData.tokenAddress,
                 userAddress,
                 {
                     defaultBlock: this._stateLayer,
@@ -63,15 +65,27 @@ export class AssetBalanceAndProxyAllowanceFetcher implements AbstractBalanceAndP
                 return new BigNumber(this._erc20Token.UNLIMITED_ALLOWANCE_IN_BASE_UNITS);
             } else {
                 const isApproved = await this._erc721Token.isProxyApprovedAsync(
-                    decodedERC721AssetData.tokenAddress,
-                    decodedERC721AssetData.tokenId,
+                    decodedAssetData.tokenAddress,
+                    decodedAssetData.tokenId,
                     {
                         defaultBlock: this._stateLayer,
                     },
                 );
-                const proxyAllowance = isApproved ? new BigNumber(1) : new BigNumber(0);
-                return proxyAllowance;
+                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,
+                    userAddress,
+                )).dividedToIntegerBy(nestedAmountElement);
+                if (_.isUndefined(proxyAllowance) || nestedAssetAllowance.lessThan(proxyAllowance)) {
+                    proxyAllowance = nestedAssetAllowance;
+                }
             }
         }
+        return proxyAllowance as BigNumber;
     }
 }