Update version numbers.

Add source for Metamask future fix.
Consolidate switch statement to one return

packages/0x.js/CHANGELOG.json

@@ -1,6 +1,6 @@
 [
     {
-        "version": "pending",
+        "version": "1.0.1-rc.4",
         "changes": [
             {
                 "pr": 914,

packages/0x.js/src/0x.ts

@@ -237,7 +237,7 @@ export class ZeroEx {
      * @param   orderHash       Hex encoded orderHash to sign.
      * @param   signerAddress   The hex encoded Ethereum address you wish to sign it with. This address
      *          must be available via the Provider supplied to 0x.js.
-     * @param   signerType the type signer that will perform the `eth_sign` operation. E.g Default, Metamask, Ledger or Trezor.
+     * @param   signerType the signer type that will perform the `eth_sign` operation. E.g Default, Metamask, Ledger or Trezor.
      *          Some implementations exhibit different behaviour. Default will assume a spec compliant eth_sign implementation.
      *          This parameter is defaulted to `SignerType.Default`.
      * @return  A hex encoded string of the Elliptic curve signature parameters generated by signing the orderHash and signature type.

packages/order-utils/CHANGELOG.json

@@ -1,6 +1,6 @@
 [
     {
-        "version": "pending",
+        "version": "1.0.1-rc.4",
         "changes": [
             {
                 "pr": 914,

packages/order-utils/src/signature_utils.ts

@@ -216,6 +216,7 @@ export async function ecSignOrderHashAsync(
     let msgHashHex = orderHash;
     const prefixedMsgHashHex = addSignedMessagePrefix(orderHash, signerType);
     // Metamask incorrectly implements eth_sign and does not prefix the message as per the spec
+    // Source: https://github.com/MetaMask/metamask-extension/commit/a9d36860bec424dcee8db043d3e7da6a5ff5672e
     if (signerType === SignerType.Metamask) {
         msgHashHex = prefixedMsgHashHex;
     }
@@ -260,22 +261,23 @@ export function convertECSignatureToSignatureHex(ecSignature: ECSignature, signe
         ethUtil.toBuffer(ecSignature.s),
     ]);
     const signatureHex = `0x${signatureBuffer.toString('hex')}`;
+    let signatureType;
     switch (signerType) {
         case SignerType.Metamask:
         case SignerType.Ledger:
         case SignerType.Default: {
-            const signatureType = SignatureType.EthSign;
-            const signatureWithType = convertToSignatureWithType(signatureHex, signatureType);
-            return signatureWithType;
+            signatureType = SignatureType.EthSign;
+            break;
         }
         case SignerType.Trezor: {
-            const signatureType = SignatureType.Trezor;
-            const signatureWithType = convertToSignatureWithType(signatureHex, signatureType);
-            return signatureWithType;
+            signatureType = SignatureType.Trezor;
+            break;
         }
         default:
             throw new Error(`Unrecognized SignerType: ${signerType}`);
     }
+    const signatureWithType = convertToSignatureWithType(signatureHex, signatureType);
+    return signatureWithType;
 }
 /**
  * Combines the signature proof and the Signature Type.

packages/types/CHANGELOG.json

@@ -1,6 +1,6 @@
 [
     {
-        "version": "pending",
+        "version": "1.0.1-rc.4",
         "changes": [
             {
                 "pr": 914,