1 files changed, 56 insertions, 0 deletions
diff --git a/packages/instant/src/util/format.ts b/packages/instant/src/util/format.ts
new file mode 100644
index 000000000..44661d697
--- /dev/null
+++ b/packages/instant/src/util/format.ts
@@ -0,0 +1,56 @@
+import { BigNumber } from '@0x/utils';
+import { Web3Wrapper } from '@0x/web3-wrapper';
+import * as _ from 'lodash';
+
+import { ETH_DECIMALS } from '../constants';
+
+export const format = {
+    ethBaseAmount: (
+        ethBaseAmount?: BigNumber,
+        decimalPlaces: number = 4,
+        defaultText: React.ReactNode = '0 ETH',
+    ): React.ReactNode => {
+        if (_.isUndefined(ethBaseAmount)) {
+            return defaultText;
+        }
+        const ethUnitAmount = Web3Wrapper.toUnitAmount(ethBaseAmount, ETH_DECIMALS);
+        return format.ethUnitAmount(ethUnitAmount, decimalPlaces);
+    },
+    ethUnitAmount: (
+        ethUnitAmount?: BigNumber,
+        decimalPlaces: number = 4,
+        defaultText: React.ReactNode = '0 ETH',
+    ): React.ReactNode => {
+        if (_.isUndefined(ethUnitAmount)) {
+            return defaultText;
+        }
+        const roundedAmount = ethUnitAmount.round(decimalPlaces).toDigits(decimalPlaces);
+        return `${roundedAmount} ETH`;
+    },
+    ethBaseAmountInUsd: (
+        ethBaseAmount?: BigNumber,
+        ethUsdPrice?: BigNumber,
+        decimalPlaces: number = 2,
+        defaultText: React.ReactNode = '$0.00',
+    ): React.ReactNode => {
+        if (_.isUndefined(ethBaseAmount) || _.isUndefined(ethUsdPrice)) {
+            return defaultText;
+        }
+        const ethUnitAmount = Web3Wrapper.toUnitAmount(ethBaseAmount, ETH_DECIMALS);
+        return format.ethUnitAmountInUsd(ethUnitAmount, ethUsdPrice, decimalPlaces);
+    },
+    ethUnitAmountInUsd: (
+        ethUnitAmount?: BigNumber,
+        ethUsdPrice?: BigNumber,
+        decimalPlaces: number = 2,
+        defaultText: React.ReactNode = '$0.00',
+    ): React.ReactNode => {
+        if (_.isUndefined(ethUnitAmount) || _.isUndefined(ethUsdPrice)) {
+            return defaultText;
+        }
+        return `$${ethUnitAmount.mul(ethUsdPrice).toFixed(decimalPlaces)}`;
+    },
+    ethAddress: (address: string): string => {
+        return `0x${address.slice(2, 7)}…${address.slice(-5)}`;
+    },
+};