Tons of tests around nested byte arrays and ERC721 receiver

2 files changed, 32 insertions, 10 deletions

diff --git a/packages/contracts/src/contracts/current/test/TestLibBytes/TestLibBytes.sol b/packages/contracts/src/contracts/current/test/TestLibBytes/TestLibBytes.sol
index 69554605d..0bf11b03b 100644
--- a/packages/contracts/src/contracts/current/test/TestLibBytes/TestLibBytes.sol
+++ b/packages/contracts/src/contracts/current/test/TestLibBytes/TestLibBytes.sol
@@ -155,6 +155,7 @@ contract TestLibBytes is
         return b;
     }
 
+=======
     /// @dev Reads the first 4 bytes from a byte array of arbitrary length.
     /// @param b Byte array to read first 4 bytes from.
     /// @return First 4 bytes of data.
@@ -166,4 +167,28 @@ contract TestLibBytes is
         result = readFirst4(b);
         return result;
     }
+
+    function publicReadBytes(
+        bytes memory b,
+        uint256 index)
+        public
+        pure
+        returns (bytes memory result)
+    {
+        result = readBytes(b, index);
+        return result;
+    }
+
+
+    function publicWriteBytes(
+        bytes memory b,
+        uint256 index,
+        bytes memory input)
+        public
+        pure
+        returns (bytes memory)
+    {
+        writeBytes(b, index, input);
+        return b;
+    }
 }
diff --git a/packages/contracts/src/contracts/current/utils/LibBytes/LibBytes.sol b/packages/contracts/src/contracts/current/utils/LibBytes/LibBytes.sol
index fb8359462..6351f1a46 100644
--- a/packages/contracts/src/contracts/current/utils/LibBytes/LibBytes.sol
+++ b/packages/contracts/src/contracts/current/utils/LibBytes/LibBytes.sol
@@ -300,24 +300,21 @@ contract LibBytes is
         returns (bytes memory result)
     {
         // Read length of nested bytes
-        require(
-            b.length >= index + 32,
-            GTE_32_LENGTH_REQUIRED
-        );
         uint256 nestedBytesLength = readUint256(b, index);
+        index += 32;
 
         // Assert length of <b> is valid, given
         // length of nested bytes
         require(
-            b.length >= index + 32 + nestedBytesLength,
+            b.length >= index + nestedBytesLength,
             GTE_32_LENGTH_REQUIRED
         );
 
         // Allocate memory and copy value to result
         result = new bytes(nestedBytesLength);
         memcpy(
-            getMemAddress(result) + 32,    // +32 skips array length
-            getMemAddress(b) + index + 32, // +32 skips array length
+            getMemAddress(result) + 32, // +32 skips array length
+            getMemAddress(b) + index + 32,
             nestedBytesLength
         );
 
@@ -344,9 +341,9 @@ contract LibBytes is
 
         // Copy <input> into <b>
         memcpy(
-            getMemAddress(b) + index,
-            getMemAddress(input),
-            input.length + 32 /* 32 bytes to store length */
+            getMemAddress(b) + index + 32,  // +32 to skip length of <b>
+            getMemAddress(input),           // include length of byte array
+            input.length + 32               // +32 bytes to store length
         );
     }
 }