7 files changed, 44 insertions, 54 deletions
diff --git a/packages/instant/src/util/address.ts b/packages/instant/src/util/address.ts
index 14d42d8c0..b21863a8e 100644
--- a/packages/instant/src/util/address.ts
+++ b/packages/instant/src/util/address.ts
@@ -1,6 +1,6 @@
-import { web3Wrapper } from '../util/web3_wrapper';
+import { Web3Wrapper } from '@0x/web3-wrapper';
 
-export const getBestAddress = async (): Promise<string | undefined> => {
+export const getBestAddress = async (web3Wrapper: Web3Wrapper): Promise<string | undefined> => {
     const addresses = await web3Wrapper.getAvailableAddressesAsync();
     return addresses[0];
 };
diff --git a/packages/instant/src/util/assert.ts b/packages/instant/src/util/assert.ts
index d02f58625..971c1eb96 100644
--- a/packages/instant/src/util/assert.ts
+++ b/packages/instant/src/util/assert.ts
@@ -44,7 +44,7 @@ export const assert = {
             assert.isUri(`${variableName}.imageUrl`, metaData.imageUrl);
         }
     },
-    isValidaffiliateInfo(variableName: string, affiliateInfo: AffiliateInfo): void {
+    isValidAffiliateInfo(variableName: string, affiliateInfo: AffiliateInfo): void {
         assert.isETHAddressHex(`${variableName}.recipientAddress`, affiliateInfo.feeRecipient);
         assert.isNumber(`${variableName}.percentage`, affiliateInfo.feePercentage);
         assert.assert(
diff --git a/packages/instant/src/util/big_number_input.ts b/packages/instant/src/util/big_number_input.ts
deleted file mode 100644
index 370d91a0a..000000000
--- a/packages/instant/src/util/big_number_input.ts
+++ /dev/null
@@ -1,34 +0,0 @@
-import { BigNumber } from '@0x/utils';
-import * as _ from 'lodash';
-
-/**
- *  A BigNumber extension that is more flexible about decimal strings.
- *  Such as allowing:
- *  new BigNumberInput('0.') => 0
- *  new BigNumberInput('1.') => 1
- *  new BigNumberInput('1..') => still throws
- */
-export class BigNumberInput extends BigNumber {
-    private readonly _isEndingWithDecimal: boolean;
-    constructor(numberOrString: string | number) {
-        if (_.isString(numberOrString)) {
-            const hasDecimalPeriod = _.endsWith(numberOrString, '.');
-            let internalString = numberOrString;
-            if (hasDecimalPeriod) {
-                internalString = numberOrString.slice(0, -1);
-            }
-            super(internalString);
-            this._isEndingWithDecimal = hasDecimalPeriod;
-        } else {
-            super(numberOrString);
-            this._isEndingWithDecimal = false;
-        }
-    }
-    public toDisplayString(): string {
-        const internalString = super.toString();
-        if (this._isEndingWithDecimal) {
-            return `${internalString}.`;
-        }
-        return internalString;
-    }
-}
diff --git a/packages/instant/src/util/injected_provider.ts b/packages/instant/src/util/injected_provider.ts
new file mode 100644
index 000000000..40f9e2da5
--- /dev/null
+++ b/packages/instant/src/util/injected_provider.ts
@@ -0,0 +1,16 @@
+import { Provider } from 'ethereum-types';
+import * as _ from 'lodash';
+
+export const getInjectedProvider = (): Provider => {
+    const injectedProviderIfExists = (window as any).ethereum;
+    if (!_.isUndefined(injectedProviderIfExists)) {
+        // TODO: call enable here when implementing wallet connection flow
+        return injectedProviderIfExists;
+    }
+    const injectedWeb3IfExists = (window as any).web3;
+    if (!_.isUndefined(injectedWeb3IfExists.currentProvider)) {
+        return injectedWeb3IfExists.currentProvider;
+    } else {
+        throw new Error(`No injected web3 found`);
+    }
+};
diff --git a/packages/instant/src/util/maybe_big_number.ts b/packages/instant/src/util/maybe_big_number.ts
new file mode 100644
index 000000000..9d3746e10
--- /dev/null
+++ b/packages/instant/src/util/maybe_big_number.ts
@@ -0,0 +1,25 @@
+import { BigNumber } from '@0x/utils';
+import * as _ from 'lodash';
+
+import { Maybe } from '../types';
+
+export const maybeBigNumberUtil = {
+    // converts a string to a Maybe<BigNumber>
+    // if string is a NaN, considered undefined
+    stringToMaybeBigNumber: (stringValue: string): Maybe<BigNumber> => {
+        let validBigNumber: BigNumber;
+        try {
+            validBigNumber = new BigNumber(stringValue);
+        } catch {
+            return undefined;
+        }
+
+        return validBigNumber.isNaN() ? undefined : validBigNumber;
+    },
+    areMaybeBigNumbersEqual: (val1: Maybe<BigNumber>, val2: Maybe<BigNumber>): boolean => {
+        if (!_.isUndefined(val1) && !_.isUndefined(val2)) {
+            return val1.equals(val2);
+        }
+        return _.isUndefined(val1) && _.isUndefined(val2);
+    },
+};
diff --git a/packages/instant/src/util/provider.ts b/packages/instant/src/util/provider.ts
deleted file mode 100644
index 49705fd11..000000000
--- a/packages/instant/src/util/provider.ts
+++ /dev/null
@@ -1,12 +0,0 @@
-import { Provider } from 'ethereum-types';
-
-export const getProvider = (): Provider => {
-    const injectedWeb3 = (window as any).web3 || undefined;
-    try {
-        // Use MetaMask/Mist provider
-        return injectedWeb3.currentProvider;
-    } catch (err) {
-        // Throws when user doesn't have MetaMask/Mist running
-        throw new Error(`No injected web3 found: ${err}`);
-    }
-};
diff --git a/packages/instant/src/util/web3_wrapper.ts b/packages/instant/src/util/web3_wrapper.ts
deleted file mode 100644
index 24dcd9076..000000000
--- a/packages/instant/src/util/web3_wrapper.ts
+++ /dev/null
@@ -1,5 +0,0 @@
-import { Web3Wrapper } from '@0x/web3-wrapper';
-
-import { getProvider } from './provider';
-
-export const web3Wrapper = new Web3Wrapper(getProvider());