Rename bytes.equals

2 files changed, 37 insertions, 2 deletions

diff --git a/packages/contracts/src/contracts/current/test/TestLibBytes/TestLibBytes.sol b/packages/contracts/src/contracts/current/test/TestLibBytes/TestLibBytes.sol
index 299452c96..60ee3db7f 100644
--- a/packages/contracts/src/contracts/current/test/TestLibBytes/TestLibBytes.sol
+++ b/packages/contracts/src/contracts/current/test/TestLibBytes/TestLibBytes.sol
@@ -53,12 +53,12 @@ contract TestLibBytes {
     /// @param lhs First byte array to compare.
     /// @param rhs Second byte array to compare.
     /// @return True if arrays are the same. False otherwise.
-    function publicAreBytesEqual(bytes memory lhs, bytes memory rhs)
+    function publicEquals(bytes memory lhs, bytes memory rhs)
         public
         pure
         returns (bool equal)
     {
-        equal = lhs.areBytesEqual(rhs);
+        equal = lhs.equals(rhs);
         return equal;
     }
 
diff --git a/packages/contracts/src/contracts/current/utils/LibBytes/LibBytes.sol b/packages/contracts/src/contracts/current/utils/LibBytes/LibBytes.sol
index 58ce31c70..2862ee3dd 100644
--- a/packages/contracts/src/contracts/current/utils/LibBytes/LibBytes.sol
+++ b/packages/contracts/src/contracts/current/utils/LibBytes/LibBytes.sol
@@ -258,6 +258,41 @@ library LibBytes {
         return result;
     }
 
+    /// @dev Tests equality of two byte arrays.
+    /// @param lhs First byte array to compare.
+    /// @param rhs Second byte array to compare.
+    /// @return True if arrays are the same. False otherwise.
+    function equals(
+        bytes memory lhs,
+        bytes memory rhs
+    )
+        internal
+        pure
+        returns (bool equal)
+    {
+        assembly {
+            // Get the number of words occupied by <lhs>
+            let lenFullWords := div(add(mload(lhs), 0x1F), 0x20)
+
+            // Add 1 to the number of words, to account for the length field
+            lenFullWords := add(lenFullWords, 0x1)
+
+            // Test equality word-by-word.
+            // Terminates early if there is a mismatch.
+            for {let i := 0} lt(i, lenFullWords) {i := add(i, 1)} {
+                let lhsWord := mload(add(lhs, mul(i, 0x20)))
+                let rhsWord := mload(add(rhs, mul(i, 0x20)))
+                equal := eq(lhsWord, rhsWord)
+                if eq(equal, 0) {
+                    // Break
+                    i := lenFullWords
+                }
+            }
+       }
+
+       return equal;
+    }
+
     /// @dev Reads an address from a position in a byte array.
     /// @param b Byte array containing an address.
     /// @param index Index in byte array of address.