Merge branch 'development' into fix/instant/signature-denied

* development: (914 commits)
  Unfix compiler version except for top level contracts
  Move OrderValidator to extensions
  Update CHANGELOG
  Remove assembly version of matchOrders
  Add getOrderInfo check before calling fillOrder
  Update comments and hard code function selector constants
  Fix build after rebase
  update comments
  Fix build and add back tests
  Update dependency paths
  Add OrderMatcher tests
  feat: Add OrderMatcher contract that takes spread in multiple assets by calling `matchOrders` followed by `fillOrder`
  Update CHANGELOG
  Use more efficient equality checks
  Add note about input validation
  Use more efficient check for overflow
  Check if amount == 0 before doing division
  Reapply prettier
  New relayers
  feat(sra_client.py): Test deployed pkg via tox
  ...

3 files changed, 36 insertions, 6 deletions

diff --git a/packages/instant/src/util/analytics.ts b/packages/instant/src/util/analytics.ts
index 21d3a4d9e..4faeaaf5a 100644
--- a/packages/instant/src/util/analytics.ts
+++ b/packages/instant/src/util/analytics.ts
@@ -6,6 +6,7 @@ import { GIT_SHA, HEAP_ENABLED, INSTANT_DISCHARGE_TARGET, NODE_ENV, NPM_PACKAGE_
 import {
     AffiliateInfo,
     Asset,
+    BaseCurrency,
     Network,
     OrderProcessState,
     OrderSource,
@@ -37,6 +38,7 @@ enum EventNames {
     ACCOUNT_UNLOCK_REQUESTED = 'Account - Unlock Requested',
     ACCOUNT_UNLOCK_DENIED = 'Account - Unlock Denied',
     ACCOUNT_ADDRESS_CHANGED = 'Account - Address Changed',
+    BASE_CURRENCY_CHANGED = 'Base Currency - Changed',
     PAYMENT_METHOD_DROPDOWN_OPENED = 'Payment Method - Dropdown Opened',
     PAYMENT_METHOD_OPENED_ETHERSCAN = 'Payment Method - Opened Etherscan',
     PAYMENT_METHOD_COPIED_ADDRESS = 'Payment Method - Copied Address',
@@ -48,6 +50,7 @@ enum EventNames {
     BUY_TX_SUBMITTED = 'Buy - Tx Submitted',
     BUY_TX_SUCCEEDED = 'Buy - Tx Succeeded',
     BUY_TX_FAILED = 'Buy - Tx Failed',
+    USD_PRICE_FETCH_FAILED = 'USD Price - Fetch Failed',
     INSTALL_WALLET_CLICKED = 'Install Wallet - Clicked',
     INSTALL_WALLET_MODAL_OPENED = 'Install Wallet - Modal - Opened',
     INSTALL_WALLET_MODAL_CLICKED_EXPLANATION = 'Install Wallet - Modal - Clicked Explanation',
@@ -119,6 +122,7 @@ export interface AnalyticsEventOptions {
     selectedAssetSymbol?: string;
     selectedAssetData?: string;
     selectedAssetDecimals?: number;
+    baseCurrency?: string;
 }
 export enum TokenSelectorClosedVia {
     ClickedX = 'Clicked X',
@@ -142,6 +146,7 @@ export const analytics = {
         window: Window,
         selectedAsset?: Asset,
         affiliateInfo?: AffiliateInfo,
+        baseCurrency?: BaseCurrency,
     ): AnalyticsEventOptions => {
         const affiliateAddress = affiliateInfo ? affiliateInfo.feeRecipient : 'none';
         const affiliateFeePercent = affiliateInfo ? parseFloat(affiliateInfo.feePercentage.toFixed(4)) : 0;
@@ -160,6 +165,7 @@ export const analytics = {
             selectedAssetName: selectedAsset ? selectedAsset.metaData.name : 'none',
             selectedAssetData: selectedAsset ? selectedAsset.assetData : 'none',
             instantEnvironment: INSTANT_DISCHARGE_TARGET || `Local ${NODE_ENV}`,
+            baseCurrency,
         };
         return eventOptions;
     },
@@ -171,6 +177,8 @@ export const analytics = {
     trackAccountUnlockDenied: trackingEventFnWithoutPayload(EventNames.ACCOUNT_UNLOCK_DENIED),
     trackAccountAddressChanged: (address: string) =>
         trackingEventFnWithPayload(EventNames.ACCOUNT_ADDRESS_CHANGED)({ address }),
+    trackBaseCurrencyChanged: (currencyChangedTo: BaseCurrency) =>
+        trackingEventFnWithPayload(EventNames.BASE_CURRENCY_CHANGED)({ currencyChangedTo }),
     trackPaymentMethodDropdownOpened: trackingEventFnWithoutPayload(EventNames.PAYMENT_METHOD_DROPDOWN_OPENED),
     trackPaymentMethodOpenedEtherscan: trackingEventFnWithoutPayload(EventNames.PAYMENT_METHOD_OPENED_ETHERSCAN),
     trackPaymentMethodCopiedAddress: trackingEventFnWithoutPayload(EventNames.PAYMENT_METHOD_COPIED_ADDRESS),
@@ -236,4 +244,5 @@ export const analytics = {
             fetchOrigin,
         });
     },
+    trackUsdPriceFailed: trackingEventFnWithoutPayload(EventNames.USD_PRICE_FETCH_FAILED),
 };
diff --git a/packages/instant/src/util/asset.ts b/packages/instant/src/util/asset.ts
index 13f84ef74..faaeb7c22 100644
--- a/packages/instant/src/util/asset.ts
+++ b/packages/instant/src/util/asset.ts
@@ -2,6 +2,7 @@ import { AssetBuyerError } from '@0x/asset-buyer';
 import { AssetProxyId, ObjectMap } from '@0x/types';
 import * as _ from 'lodash';
 
+import { DEFAULT_UNKOWN_ASSET_NAME } from '../constants';
 import { assetDataNetworkMapping } from '../data/asset_data_network_mapping';
 import { Asset, AssetMetaData, ERC20Asset, Network, ZeroExInstantError } from '../types';
 
@@ -71,7 +72,7 @@ export const assetUtils = {
         }
         return metaData;
     },
-    bestNameForAsset: (asset?: Asset, defaultName: string = '???'): string => {
+    bestNameForAsset: (asset?: Asset, defaultName: string = DEFAULT_UNKOWN_ASSET_NAME): string => {
         if (_.isUndefined(asset)) {
             return defaultName;
         }
diff --git a/packages/instant/src/util/format.ts b/packages/instant/src/util/format.ts
index e9c432b2f..4adb63e21 100644
--- a/packages/instant/src/util/format.ts
+++ b/packages/instant/src/util/format.ts
@@ -2,7 +2,7 @@ import { BigNumber } from '@0x/utils';
 import { Web3Wrapper } from '@0x/web3-wrapper';
 import * as _ from 'lodash';
 
-import { ETH_DECIMALS } from '../constants';
+import { BIG_NUMBER_ZERO, ETH_DECIMALS } from '../constants';
 
 export const format = {
     ethBaseUnitAmount: (
@@ -20,24 +20,38 @@ export const format = {
         ethUnitAmount?: BigNumber,
         decimalPlaces: number = 4,
         defaultText: React.ReactNode = '0 ETH',
+        minUnitAmountToDisplay: BigNumber = new BigNumber('0.00001'),
     ): React.ReactNode => {
         if (_.isUndefined(ethUnitAmount)) {
             return defaultText;
         }
-        const roundedAmount = ethUnitAmount.round(decimalPlaces).toDigits(decimalPlaces);
-        return `${roundedAmount} ETH`;
+        let roundedAmount = ethUnitAmount.round(decimalPlaces).toDigits(decimalPlaces);
+
+        if (roundedAmount.eq(BIG_NUMBER_ZERO) && ethUnitAmount.greaterThan(BIG_NUMBER_ZERO)) {
+            // Sometimes for small ETH amounts (i.e. 0.000045) the amount rounded to 4 decimalPlaces is 0
+            // If that is the case, show to 1 significant digit
+            roundedAmount = new BigNumber(ethUnitAmount.toPrecision(1));
+        }
+
+        const displayAmount =
+            roundedAmount.greaterThan(BIG_NUMBER_ZERO) && roundedAmount.lessThan(minUnitAmountToDisplay)
+                ? `< ${minUnitAmountToDisplay.toString()}`
+                : roundedAmount.toString();
+
+        return `${displayAmount} ETH`;
     },
     ethBaseUnitAmountInUsd: (
         ethBaseUnitAmount?: BigNumber,
         ethUsdPrice?: BigNumber,
         decimalPlaces: number = 2,
         defaultText: React.ReactNode = '$0.00',
+        minUnitAmountToDisplay: BigNumber = new BigNumber('0.00001'),
     ): React.ReactNode => {
         if (_.isUndefined(ethBaseUnitAmount) || _.isUndefined(ethUsdPrice)) {
             return defaultText;
         }
         const ethUnitAmount = Web3Wrapper.toUnitAmount(ethBaseUnitAmount, ETH_DECIMALS);
-        return format.ethUnitAmountInUsd(ethUnitAmount, ethUsdPrice, decimalPlaces);
+        return format.ethUnitAmountInUsd(ethUnitAmount, ethUsdPrice, decimalPlaces, minUnitAmountToDisplay);
     },
     ethUnitAmountInUsd: (
         ethUnitAmount?: BigNumber,
@@ -48,7 +62,13 @@ export const format = {
         if (_.isUndefined(ethUnitAmount) || _.isUndefined(ethUsdPrice)) {
             return defaultText;
         }
-        return `$${ethUnitAmount.mul(ethUsdPrice).toFixed(decimalPlaces)}`;
+        const rawUsdPrice = ethUnitAmount.mul(ethUsdPrice);
+        const roundedUsdPrice = rawUsdPrice.toFixed(decimalPlaces);
+        if (roundedUsdPrice === '0.00' && rawUsdPrice.gt(BIG_NUMBER_ZERO)) {
+            return '<$0.01';
+        } else {
+            return `$${roundedUsdPrice}`;
+        }
     },
     ethAddress: (address: string): string => {
         return `0x${address.slice(2, 7)}…${address.slice(-5)}`;