From f03e5c6bd12c88fffbad324fd7493d3acedea0aa Mon Sep 17 00:00:00 2001
From: Greg Hysen <greg.hysen@gmail.com>
Date: Fri, 1 Jun 2018 11:34:45 -0700
Subject: Style audit proxies

---
 .../current/protocol/AssetProxy/ERC20Proxy.sol     |  8 +++-
 .../current/protocol/AssetProxy/ERC721Proxy.sol    | 33 ++++++++++++-----
 .../TestAssetDataDecoders.sol                      | 43 +++++++++++++++++-----
 3 files changed, 64 insertions(+), 20 deletions(-)

diff --git a/packages/contracts/src/contracts/current/protocol/AssetProxy/ERC20Proxy.sol b/packages/contracts/src/contracts/current/protocol/AssetProxy/ERC20Proxy.sol
index 11383adaf..54cbeb963 100644
--- a/packages/contracts/src/contracts/current/protocol/AssetProxy/ERC20Proxy.sol
+++ b/packages/contracts/src/contracts/current/protocol/AssetProxy/ERC20Proxy.sol
@@ -79,7 +79,10 @@ contract ERC20Proxy is
         return PROXY_ID;
     }
 
-    /// @dev Decodes ERC20 Asset Proxy data
+    /// @dev Decodes ERC20 Asset data.
+    /// @param assetData Encoded byte array.
+    /// @return proxyId Intended ERC20 proxy id.
+    /// @return token ERC20 token address.
     function decodeERC20AssetData(bytes memory assetData)
         internal
         pure
@@ -88,10 +91,13 @@ contract ERC20Proxy is
             address token
         )
     {
+        // Validate encoded data length
         require(
             assetData.length == 21,
             INVALID_ASSET_DATA_LENGTH
         );
+
+        // Decode data
         proxyId = uint8(assetData[0]);
         token = readAddress(assetData, 1);
 
diff --git a/packages/contracts/src/contracts/current/protocol/AssetProxy/ERC721Proxy.sol b/packages/contracts/src/contracts/current/protocol/AssetProxy/ERC721Proxy.sol
index 9dac02d87..58c23b03b 100644
--- a/packages/contracts/src/contracts/current/protocol/AssetProxy/ERC721Proxy.sol
+++ b/packages/contracts/src/contracts/current/protocol/AssetProxy/ERC721Proxy.sol
@@ -53,7 +53,7 @@ contract ERC721Proxy is
             uint8 proxyId,
             address token,
             uint256 tokenId,
-            bytes memory data
+            bytes memory receiverData
         ) = decodeERC721AssetData(assetData);
 
         // Data must be intended for this proxy.
@@ -76,11 +76,10 @@ contract ERC721Proxy is
             INVALID_AMOUNT
         );
 
-        // Transfer token.
-        // Save gas by calling safeTransferFrom only when there is data present.
-        // Either succeeds or throws.
-        if(data.length > 0) {
-            ERC721Token(token).safeTransferFrom(from, to, tokenId, data);
+        // Transfer token. Saves gas by calling safeTransferFrom only
+        // when there is receiverData present. Either succeeds or throws.
+        if(receiverData.length > 0) {
+            ERC721Token(token).safeTransferFrom(from, to, tokenId, receiverData);
         } else {
             ERC721Token(token).transferFrom(from, to, tokenId);
         }
@@ -96,7 +95,13 @@ contract ERC721Proxy is
         return PROXY_ID;
     }
 
-    /// @dev Decodes ERC721 Asset Proxy data
+    /// @dev Decodes ERC721 Asset data.
+    /// @param assetData Encoded byte array.
+    /// @return proxyId Intended ERC721 proxy id.
+    /// @return token ERC721 token address.
+    /// @return tokenId ERC721 token id.
+    /// @return receiverData Additional data with no specific format, which
+    ///                      is passed to the receiving contract's onERC721Received.
     function decodeERC721AssetData(bytes memory assetData)
         internal
         pure
@@ -104,20 +109,28 @@ contract ERC721Proxy is
             uint8 proxyId,
             address token,
             uint256 tokenId,
-            bytes memory data
+            bytes memory receiverData
         )
     {
+        // Validate encoded data length
         require(
             assetData.length >= 53,
             INVALID_ASSET_DATA_LENGTH
         );
+
+        // Decode asset data
         proxyId = uint8(assetData[0]);
         token = readAddress(assetData, 1);
         tokenId = readUint256(assetData, 21);
         if (assetData.length > 53) {
-            data = readBytes(assetData, 53);
+            receiverData = readBytes(assetData, 53);
         }
 
-        return (proxyId, token, tokenId, data);
+        return (
+            proxyId,
+            token,
+            tokenId,
+            receiverData
+        );
     }
 }
diff --git a/packages/contracts/src/contracts/current/test/TestAssetDataDecoders/TestAssetDataDecoders.sol b/packages/contracts/src/contracts/current/test/TestAssetDataDecoders/TestAssetDataDecoders.sol
index 45787d88b..2c6a8fdb0 100644
--- a/packages/contracts/src/contracts/current/test/TestAssetDataDecoders/TestAssetDataDecoders.sol
+++ b/packages/contracts/src/contracts/current/test/TestAssetDataDecoders/TestAssetDataDecoders.sol
@@ -27,26 +27,51 @@ contract TestAssetDataDecoders is
     ERC721Proxy
 {
 
-    /// @dev Decodes ERC721 Asset Proxy data
+    /// @dev Decodes ERC20 Asset data.
+    /// @param assetData Encoded byte array.
+    /// @return proxyId Intended ERC20 proxy id.
+    /// @return token ERC20 token address.
     function publicDecodeERC20Data(bytes memory assetData)
         public
         pure
-        returns (uint8, address)
+        returns (
+            uint8 proxyId,
+            address token
+        )
     {
-        return ERC20Proxy.decodeERC20AssetData(assetData);
+        (proxyId, token) = decodeERC20AssetData(assetData);
+        return (proxyId, token);
     }
 
-    /// @dev Decodes ERC721 Asset Proxy data
+    /// @dev Decodes ERC721 Asset data.
+    /// @param assetData Encoded byte array.
+    /// @return proxyId Intended ERC721 proxy id.
+    /// @return token ERC721 token address.
+    /// @return tokenId ERC721 token id.
+    /// @return receiverData Additional data with no specific format, which
+    ///                      is passed to the receiving contract's onERC721Received.
     function publicDecodeERC721Data(bytes memory assetData)
         public
         pure
         returns (
-            uint8,
-            address,
-            uint256,
-            bytes memory
+            uint8 proxyId,
+            address token,
+            uint256 tokenId,
+            bytes memory receiverData
         )
     {
-        return ERC721Proxy.decodeERC721AssetData(assetData);
+        (
+            proxyId,
+            token,
+            tokenId,
+            receiverData
+        ) = decodeERC721AssetData(assetData);
+
+        return (
+            proxyId,
+            token,
+            tokenId,
+            receiverData
+        );
     }
 }
-- 
cgit