feat: bytes32 name and symbol (#34)

m0-foundation · Jul 23, 2024 · 45aa01d · 45aa01d
1 parent e809402
commit 45aa01d
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Showing 12 changed files with 183 additions and 28 deletions.
diff --git a/src/ERC20Extended.sol b/src/ERC20Extended.sol
@@ -5,6 +5,8 @@ pragma solidity 0.8.23;
 import { IERC20 } from "./interfaces/IERC20.sol";
 import { IERC20Extended } from "./interfaces/IERC20Extended.sol";
 
+import { Bytes32String } from "./libs/Bytes32String.sol";
+
 import { ERC3009 } from "./ERC3009.sol";
 
 /**
@@ -25,8 +27,8 @@ abstract contract ERC20Extended is IERC20Extended, ERC3009 {
     /// @inheritdoc IERC20
     uint8 public immutable decimals;
 
-    /// @inheritdoc IERC20
-    string public symbol;
+    /// @dev The symbol of the token (stored as a bytes32 instead of a string in order to be immutable).
+    bytes32 internal immutable _symbol;
 
     /// @inheritdoc IERC20
     mapping(address account => mapping(address spender => uint256 allowance)) public allowance;
@@ -40,7 +42,7 @@ abstract contract ERC20Extended is IERC20Extended, ERC3009 {
      * @param  decimals_ The number of decimals the token uses.
      */
     constructor(string memory name_, string memory symbol_, uint8 decimals_) ERC3009(name_) {
-        symbol = symbol_;
+        _symbol = Bytes32String.toBytes32(symbol_);
         decimals = decimals_;
     }
 
@@ -102,8 +104,13 @@ abstract contract ERC20Extended is IERC20Extended, ERC3009 {
     /* ============ View/Pure Functions ============ */
 
     /// @inheritdoc IERC20
-    function name() external view returns (string memory name_) {
-        return _name;
+    function name() external view returns (string memory) {
+        return Bytes32String.toString(_name);
+    }
+
+    /// @inheritdoc IERC20
+    function symbol() external view returns (string memory) {
+        return Bytes32String.toString(_symbol);
     }
 
     /* ============ Internal Interactive Functions ============ */

diff --git a/src/ERC712Extended.sol b/src/ERC712Extended.sol
@@ -6,6 +6,7 @@ import { IERC712 } from "./interfaces/IERC712.sol";
 import { IERC712Extended } from "./interfaces/IERC712Extended.sol";
 
 import { SignatureChecker } from "./libs/SignatureChecker.sol";
+import { Bytes32String } from "./libs/Bytes32String.sol";
 
 /**
  * @title  Typed structured data hashing and signing via EIP-712, extended by EIP-5267.
@@ -27,8 +28,8 @@ abstract contract ERC712Extended is IERC712Extended {
     /// @dev Initial EIP-712 domain separator set at deployment.
     bytes32 internal immutable _INITIAL_DOMAIN_SEPARATOR;
 
-    /// @dev The name of the contract.
-    string internal _name;
+    /// @dev The name of the contract (stored as a bytes32 instead of a string in order to be immutable).
+    bytes32 internal immutable _name;
 
     /* ============ Constructor ============ */
 
@@ -37,7 +38,7 @@ abstract contract ERC712Extended is IERC712Extended {
      * @param  name_ The name of the contract.
      */
     constructor(string memory name_) {
-        _name = name_;
+        _name = Bytes32String.toBytes32(name_);
 
         _INITIAL_CHAIN_ID = block.chainid;
         _INITIAL_DOMAIN_SEPARATOR = _getDomainSeparator();
@@ -62,7 +63,7 @@ abstract contract ERC712Extended is IERC712Extended {
     {
         return (
             hex"0f", // 01111
-            _name,
+            Bytes32String.toString(_name),
             "1",
             block.chainid,
             address(this),
@@ -87,7 +88,7 @@ abstract contract ERC712Extended is IERC712Extended {
             keccak256(
                 abi.encode(
                     _EIP712_DOMAIN_HASH,
-                    keccak256(bytes(_name)),
+                    keccak256(bytes(Bytes32String.toString(_name))),
                     _EIP712_VERSION_HASH,
                     block.chainid,
                     address(this)

diff --git a/src/libs/Bytes32String.sol b/src/libs/Bytes32String.sol
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-3.0
+
+pragma solidity 0.8.23;
+
+/**
+ * @title  A library to convert between string and bytes32 (assuming 32 characters or less).
+ * @author M^0 Labs
+ */
+library Bytes32String {
+    function toBytes32(string memory input_) internal pure returns (bytes32) {
+        return bytes32(abi.encodePacked(input_));
+    }
+
+    function toString(bytes32 input_) internal pure returns (string memory) {
+        uint256 length_;
+
+        while (length_ < 32 && uint8(input_[length_]) != 0) {
+            ++length_;
+        }
+
+        bytes memory name_ = new bytes(length_);
+
+        for (uint256 index_; index_ < length_; ++index_) {
+            name_[index_] = input_[index_];
+        }
+
+        return string(name_);
+    }
+}
diff --git a/src/ContractHelper.sol → src/libs/ContractHelper.sol b/src/ContractHelper.sol → src/libs/ContractHelper.sol
diff --git a/test/Bytes32String.sol b/test/Bytes32String.sol
@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: UNLICENSED
+
+pragma solidity 0.8.23;
+
+import { Test } from "../lib/forge-std/src/Test.sol";
+
+import { Bytes32StringHarness } from "./utils/Bytes32StringHarness.sol";
+
+contract Bytes32StringTests is Test {
+    Bytes32StringHarness internal _bytes32String;
+
+    function setUp() external {
+        _bytes32String = new Bytes32StringHarness();
+    }
+
+    function test_full() external {
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("")), "");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("T")), "T");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Te")), "Te");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Tes")), "Tes");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test")), "Test");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1")), "Test1");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1-")), "Test1-");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1-T")), "Test1-T");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1-Te")), "Test1-Te");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1-Tes")), "Test1-Tes");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1-Test")), "Test1-Test");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1-Test2")), "Test1-Test2");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-")), "Test1-Test2-");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-T")), "Test1-Test2-T");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Te")), "Test1-Test2-Te");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Tes")), "Test1-Test2-Tes");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test")), "Test1-Test2-Test");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3")), "Test1-Test2-Test3");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-")), "Test1-Test2-Test3-");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-T")), "Test1-Test2-Test3-T");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-Te")), "Test1-Test2-Test3-Te");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-Tes")), "Test1-Test2-Test3-Tes");
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-Test")), "Test1-Test2-Test3-Test");
+        assertEq(
+            _bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-Test4")),
+            "Test1-Test2-Test3-Test4"
+        );
+        assertEq(
+            _bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-Test4-")),
+            "Test1-Test2-Test3-Test4-"
+        );
+        assertEq(
+            _bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-Test4-T")),
+            "Test1-Test2-Test3-Test4-T"
+        );
+        assertEq(
+            _bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-Test4-Te")),
+            "Test1-Test2-Test3-Test4-Te"
+        );
+        assertEq(
+            _bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-Test4-Tes")),
+            "Test1-Test2-Test3-Test4-Tes"
+        );
+        assertEq(
+            _bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-Test4-Test")),
+            "Test1-Test2-Test3-Test4-Test"
+        );
+        assertEq(
+            _bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-Test4-Test5")),
+            "Test1-Test2-Test3-Test4-Test5"
+        );
+        assertEq(
+            _bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-Test4-Test5-")),
+            "Test1-Test2-Test3-Test4-Test5-"
+        );
+        assertEq(
+            _bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-Test4-Test5-T")),
+            "Test1-Test2-Test3-Test4-Test5-T"
+        );
+        assertEq(
+            _bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-Test4-Test5-Te")),
+            "Test1-Test2-Test3-Test4-Test5-Te"
+        );
+
+        // Beyond this point, input is larger than 32 bytes, so it is truncated.
+        assertEq(
+            _bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-Test4-Test5-Tes")),
+            "Test1-Test2-Test3-Test4-Test5-Te"
+        );
+        assertEq(
+            _bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-Test4-Test5-Test")),
+            "Test1-Test2-Test3-Test4-Test5-Te"
+        );
+        assertEq(
+            _bytes32String.toString(_bytes32String.toBytes32("Test1-Test2-Test3-Test4-Test5-Test6")),
+            "Test1-Test2-Test3-Test4-Test5-Te"
+        );
+    }
+
+    function testFuzz_full(string memory input_) external {
+        assertEq(_bytes32String.toString(_bytes32String.toBytes32(input_)), _truncate32(input_));
+    }
+
+    function _truncate32(string memory input_) internal pure returns (string memory) {
+        bytes memory bytesIn_ = bytes(input_);
+
+        if (bytesIn_.length <= 32) return input_;
+
+        bytes memory bytesOut_ = new bytes(32);
+
+        for (uint256 index_; index_ < 32; ++index_) {
+            bytesOut_[index_] = bytesIn_[index_];
+        }
+
+        return string(bytesOut_);
+    }
+}
diff --git a/test/ERC3009.t.sol b/test/ERC3009.t.sol
@@ -30,7 +30,7 @@ contract ERC3009Tests is TestUtils {
         _token = new ERC20ExtendedHarness("ERC3009 Token", "ERC3009_TKN", 0);
     }
 
-    /* ============ Typehashes ============ */
+    /* ============ TypeHashes ============ */
     function test_transferWithAuthorizationTypehash() external {
         assertEq(
             _token.TRANSFER_WITH_AUTHORIZATION_TYPEHASH(),

diff --git a/test/ERC712Extended.t.sol b/test/ERC712Extended.t.sol
@@ -40,7 +40,6 @@ contract ERC712ExtendedTests is TestUtils {
 
     /* ============ constructor ============ */
     function test_constructor() external {
-        assertEq(_erc712.name(), _name);
         assertEq(_erc712.DOMAIN_SEPARATOR(), _computeDomainSeparator(_name, block.chainid, address(_erc712)));
     }
 

diff --git a/test/invariant/ERC20ExtendedInvariant.t.sol b/test/invariant/ERC20ExtendedInvariant.t.sol
@@ -37,7 +37,7 @@ contract ERC20ExtendedHandler is CommonBase, StdCheats, StdUtils {
         _token.approve(to_, amount_);
     }
 
-    function transferfrom(address from_, address to_, uint256 amount_) public {
+    function transferFrom(address from_, address to_, uint256 amount_) public {
         if (from_ == address(0) || to_ == address(0)) return;
 
         amount_ = bound(amount_, 0, _token.balanceOf(from_));
@@ -87,7 +87,7 @@ contract ERC20ExtendedInvariantTests is TestUtils {
         selectors[0] = ERC20ExtendedHandler.mint.selector;
         selectors[1] = ERC20ExtendedHandler.burn.selector;
         selectors[2] = ERC20ExtendedHandler.approve.selector;
-        selectors[3] = ERC20ExtendedHandler.transferfrom.selector;
+        selectors[3] = ERC20ExtendedHandler.transferFrom.selector;
         selectors[4] = ERC20ExtendedHandler.transfer.selector;
 
         targetSelector(FuzzSelector({ addr: address(_handler), selectors: selectors }));

diff --git a/test/utils/Bytes32StringHarness.sol b/test/utils/Bytes32StringHarness.sol
@@ -0,0 +1,16 @@
+// SPDX-License-Identifier: GPL-3.0
+
+pragma solidity 0.8.23;
+
+import { Bytes32String } from "../../src/libs/Bytes32String.sol";
+
+/// @title Bytes32String harness used to correctly display test coverage.
+contract Bytes32StringHarness {
+    function toBytes32(string memory input_) external pure returns (bytes32) {
+        return Bytes32String.toBytes32(input_);
+    }
+
+    function toString(bytes32 input_) external pure returns (string memory) {
+        return Bytes32String.toString(input_);
+    }
+}
diff --git a/test/utils/ContractHelperHarness.sol b/test/utils/ContractHelperHarness.sol
@@ -2,7 +2,7 @@
 
 pragma solidity 0.8.23;
 
-import { ContractHelper } from "../../src/ContractHelper.sol";
+import { ContractHelper } from "../../src/libs/ContractHelper.sol";
 
 /// @title ContractHelper harness used to correctly display test coverage.
 contract ContractHelperHarness {

diff --git a/test/utils/ERC20ExtendedHarness.sol b/test/utils/ERC20ExtendedHarness.sol
@@ -11,9 +11,7 @@ contract ERC20ExtendedHarness is ERC20Extended {
 
     constructor(string memory name_, string memory symbol_, uint8 decimals_) ERC20Extended(name_, symbol_, decimals_) {}
 
-    /******************************************************************************************************************\
-    |                                      External/Public Interactive Functions                                       |
-    \******************************************************************************************************************/
+    /* ============ Interactive Functions ============ */
 
     function mint(address recipient_, uint256 amount_) external {
         _transfer(address(0), recipient_, amount_);
@@ -27,9 +25,7 @@ contract ERC20ExtendedHarness is ERC20Extended {
         authorizationState[authorizer_][nonce_] = isNonceUsed_;
     }
 
-    /******************************************************************************************************************\
-    |                                       External/Public View/Pure Functions                                        |
-    \******************************************************************************************************************/
+    /* ============ View/Pure Functions ============ */
 
     function getDigest(bytes32 internalDigest_) external view returns (bytes32) {
         return _getDigest(internalDigest_);
@@ -71,9 +67,7 @@ contract ERC20ExtendedHarness is ERC20Extended {
         return _getCancelAuthorizationDigest(authorizer_, nonce_);
     }
 
-    /******************************************************************************************************************\
-    |                                          Internal Interactive Functions                                          |
-    \******************************************************************************************************************/
+    /* ============ Internal Interactive Functions ============ */
 
     function _transfer(address sender_, address recipient_, uint256 amount_) internal override {
         if (sender_ != address(0)) {

diff --git a/test/utils/ERC712ExtendedHarness.sol b/test/utils/ERC712ExtendedHarness.sol
@@ -7,10 +7,6 @@ import { ERC712Extended } from "../../src/ERC712Extended.sol";
 contract ERC712ExtendedHarness is ERC712Extended {
     constructor(string memory name_) ERC712Extended(name_) {}
 
-    function name() external view returns (string memory) {
-        return _name;
-    }
-
     function getDomainSeparator() external view returns (bytes32) {
         return _getDomainSeparator();
     }