Get rid of react-shared as a dependency, write own etherscanUtil

packages/instant/src/util/etherscan.ts

@@ -0,0 +1,24 @@
+import * as _ from 'lodash';
+
+import { Network } from '../types';
+
+const etherscanPrefix = (networkId: number): string | undefined => {
+    switch (networkId) {
+        case Network.Kovan:
+            return 'kovan.';
+        case Network.Mainnet:
+            return '';
+        default:
+            return undefined;
+    }
+};
+
+export const etherscanUtil = {
+    getEtherScanTxnAddressIfExists: (txnHash: string, networkId: number) => {
+        const prefix = etherscanPrefix(networkId);
+        if (_.isUndefined(prefix)) {
+            return;
+        }
+        return `https://${prefix}etherscan.io/tx/${txnHash}`;
+    },
+};