Use last byte of signature as signature type

3 files changed, 28 insertions, 32 deletions

diff --git a/packages/contracts/test/exchange/core.ts b/packages/contracts/test/exchange/core.ts
index be8d14cb0..bc476a5ee 100644
--- a/packages/contracts/test/exchange/core.ts
+++ b/packages/contracts/test/exchange/core.ts
@@ -460,10 +460,11 @@ describe('Exchange core', () => {
                 makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(10), 18),
             });
 
+            const v = ethUtil.toBuffer(signedOrder.signature.slice(0, 4));
             const invalidR = ethUtil.sha3('invalidR');
             const invalidS = ethUtil.sha3('invalidS');
-            const signatureTypeAndV = signedOrder.signature.slice(0, 6);
-            const invalidSigBuff = Buffer.concat([ethUtil.toBuffer(signatureTypeAndV), invalidR, invalidS]);
+            const signatureType = ethUtil.toBuffer(`0x${signedOrder.signature.slice(-2)}`);
+            const invalidSigBuff = Buffer.concat([v, invalidR, invalidS, signatureType]);
             const invalidSigHex = `0x${invalidSigBuff.toString('hex')}`;
             signedOrder.signature = invalidSigHex;
             return expect(exchangeWrapper.fillOrderAsync(signedOrder, takerAddress)).to.be.rejectedWith(
diff --git a/packages/contracts/test/exchange/signature_validator.ts b/packages/contracts/test/exchange/signature_validator.ts
index 376fff438..ca679e344 100644
--- a/packages/contracts/test/exchange/signature_validator.ts
+++ b/packages/contracts/test/exchange/signature_validator.ts
@@ -75,13 +75,11 @@ describe('MixinSignatureValidator', () => {
         });
 
         it('should return false with an invalid signature', async () => {
+            const v = ethUtil.toBuffer(signedOrder.signature.slice(0, 4));
             const invalidR = ethUtil.sha3('invalidR');
             const invalidS = ethUtil.sha3('invalidS');
-            const invalidSigBuff = Buffer.concat([
-                ethUtil.toBuffer(signedOrder.signature.slice(0, 6)),
-                invalidR,
-                invalidS,
-            ]);
+            const signatureType = ethUtil.toBuffer(`0x${signedOrder.signature.slice(-2)}`);
+            const invalidSigBuff = Buffer.concat([v, invalidR, invalidS, signatureType]);
             const invalidSigHex = `0x${invalidSigBuff.toString('hex')}`;
             signedOrder.signature = invalidSigHex;
             const orderHashHex = orderUtils.getOrderHashHex(signedOrder);
diff --git a/packages/contracts/test/libraries/lib_bytes.ts b/packages/contracts/test/libraries/lib_bytes.ts
index c85cee5e3..4eedad25d 100644
--- a/packages/contracts/test/libraries/lib_bytes.ts
+++ b/packages/contracts/test/libraries/lib_bytes.ts
@@ -22,6 +22,7 @@ describe('LibBytes', () => {
     let owner: string;
     let libBytes: TestLibBytesContract;
     const byteArrayShorterThan32Bytes = '0x012345';
+    const byteArrayShorterThan20Bytes = byteArrayShorterThan32Bytes;
     const byteArrayLongerThan32Bytes =
         '0x0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef';
     const byteArrayLongerThan32BytesFirstBytesSwapped =
@@ -60,39 +61,35 @@ describe('LibBytes', () => {
         await blockchainLifecycle.revertAsync();
     });
 
-    describe('deepCopyBytes', () => {
-        const byteArrayLongerThan32BytesLen = (byteArrayLongerThan32Bytes.length - 2) / 2;
-        it('should return a byte array of length 0 if len is 0', async () => {
-            const index = new BigNumber(0);
-            const len = new BigNumber(0);
-            const copy = await libBytes.publicDeepCopyBytes.callAsync(byteArrayLongerThan32Bytes, index, len);
-            expect(copy).to.equal(constants.NULL_BYTES);
+    describe('popByte', () => {
+        it('should revert if length is 0', async () => {
+            return expect(libBytes.publicPopByte.callAsync(constants.NULL_BYTES)).to.be.rejectedWith(constants.REVERT);
         });
 
-        it('should throw if start index + length to copy is greater than length of byte array', async () => {
-            const index = new BigNumber(0);
-            const len = new BigNumber(byteArrayLongerThan32BytesLen + 1);
-            return expect(
-                libBytes.publicDeepCopyBytes.callAsync(byteArrayLongerThan32Bytes, index, len),
-            ).to.be.rejectedWith(constants.REVERT);
+        it('should pop the last byte from the input and return it', async () => {
+            const [newBytes, poppedByte] = await libBytes.publicPopByte.callAsync(byteArrayLongerThan32Bytes);
+            const expectedNewBytes = byteArrayLongerThan32Bytes.slice(0, -2);
+            const expectedPoppedByte = `0x${byteArrayLongerThan32Bytes.slice(-2)}`;
+            expect(newBytes).to.equal(expectedNewBytes);
+            expect(poppedByte).to.equal(expectedPoppedByte);
         });
+    });
 
-        it('should copy the entire byte array if index = 0 and len = b.length', async () => {
-            const index = new BigNumber(0);
-            const len = new BigNumber(byteArrayLongerThan32BytesLen);
-            const copy = await libBytes.publicDeepCopyBytes.callAsync(byteArrayLongerThan32Bytes, index, len);
-            expect(copy).to.equal(byteArrayLongerThan32Bytes);
+    describe('popAddress', () => {
+        it('should revert if length is less than 20', async () => {
+            return expect(libBytes.publicPopAddress.callAsync(byteArrayShorterThan20Bytes)).to.be.rejectedWith(
+                constants.REVERT,
+            );
         });
 
-        it('should copy part of the byte array if area to copy is less than b.length', async () => {
-            const index = new BigNumber(10);
-            const len = new BigNumber(4);
-            const copy = await libBytes.publicDeepCopyBytes.callAsync(byteArrayLongerThan32Bytes, index, len);
-            const expectedCopy = `0x${byteArrayLongerThan32Bytes.slice(22, 30)}`;
-            expect(copy).to.equal(expectedCopy);
+        it('should pop the last 20 bytes from the input and return it', async () => {
+            const [newBytes, poppedAddress] = await libBytes.publicPopAddress.callAsync(byteArrayLongerThan32Bytes);
+            const expectedNewBytes = byteArrayLongerThan32Bytes.slice(0, -40);
+            const expectedPoppedAddress = `0x${byteArrayLongerThan32Bytes.slice(-40)}`;
+            expect(newBytes).to.equal(expectedNewBytes);
+            expect(poppedAddress).to.equal(expectedPoppedAddress);
         });
     });
-
     describe('areBytesEqual', () => {
         it('should return true if byte arrays are equal (both arrays < 32 bytes)', async () => {
             const areBytesEqual = await libBytes.publicAreBytesEqual.callAsync(