Implement precompile mock contracts and foundry mock util test contra…

…cts (#462)

- Add foundry test support files
- Add husky commit-msg to help devs not forget signing off
- Add foundry testing readme file
- Add npm package script for easy runs of foundry, hardhat and localnode
- Add HTS mock and test contracts and use for reference foundry tests
- Add github CI action to run foundry tests

---------

Signed-off-by: Mo Shaikjee <[email protected]>

.github/workflows/foundry_test.yml

@@ -0,0 +1,46 @@
+name: Foundry Tests
+
+on:
+  workflow_dispatch:
+  pull_request:
+    branches: [main]
+
+jobs:
+  check:
+    strategy:
+      fail-fast: true
+
+    name: Foundry project
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          submodules: recursive
+
+      - name: Use Node.js [18.15]
+        uses: actions/setup-node@v3
+        with:
+          node-version: 18.15
+          cache: npm
+
+      - name: Create .env file
+        run: cp local.env .env
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Install Foundry
+        uses: foundry-rs/foundry-toolchain@v1
+        with:
+          version: nightly
+
+      - name: Run Forge build
+        run: |
+          forge --version
+          forge build
+        id: build
+
+      - name: Run Forge tests
+        run: |
+          forge test -vvv
+        id: test

.github/workflows/test-workflow.yml

@@ -40,6 +40,11 @@ jobs:
       - name: Install dependencies
         run: npm ci
 
+      - name: Install Foundry
+        uses: foundry-rs/foundry-toolchain@v1
+        with:
+          version: nightly
+
       - name: Start the local node
         run: npx hedera start -d --network local
         timeout-minutes: 5

.gitignore

@@ -10,3 +10,24 @@ artifacts/contracts
 .env
 test-results.*
 
+## --- Foundry Gitignore ---
+
+# Compiler files
+forge-cache/
+out/
+
+# Ignores development broadcast logs
+!/broadcast
+/broadcast/*/31337/
+/broadcast/**/dry-run/
+
+# Docs
+docs/
+
+# Coverage
+lcov.info
+coverage/
+
+## --- Hardhat Gitignore for Foundry artifacts ---
+artifacts/forge-std
+artifacts/ds-test

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "lib/forge-std"]
+	path = lib/forge-std
+	url = https://github.com/foundry-rs/forge-std

.husky/commit-msg

@@ -0,0 +1,4 @@
+#!/usr/bin/env sh
+. "$(dirname -- "$0")/_/husky.sh"
+
+grep -q "Signed-off-by" $1 || (echo "No Signed-off-by found. Run git commit --signoff" && false)

FOUNDRY_TESTING.md

@@ -0,0 +1,66 @@
+## Foundry
+
+**Foundry is a blazing fast, portable and modular toolkit for Ethereum application development written in Rust.**
+
+Foundry consists of:
+
+-   **Forge**: Ethereum testing framework (like Truffle, Hardhat and DappTools).
+-   **Cast**: Swiss army knife for interacting with EVM smart contracts, sending transactions and getting chain data.
+-   **Anvil**: Local Ethereum node, akin to Ganache, Hardhat Network.
+-   **Chisel**: Fast, utilitarian, and verbose solidity REPL.
+
+## Documentation
+
+https://book.getfoundry.sh/
+
+## Usage
+
+### Build
+
+```shell
+$ forge build
+```
+
+### Test
+
+```shell
+$ forge test
+```
+
+### Format
+
+```shell
+$ forge fmt
+```
+
+### Gas Snapshots
+
+```shell
+$ forge snapshot
+```
+
+### Anvil
+
+```shell
+$ anvil
+```
+
+### Deploy
+
+```shell
+$ forge script script/Counter.s.sol:CounterScript --rpc-url <your_rpc_url> --private-key <your_private_key>
+```
+
+### Cast
+
+```shell
+$ cast <subcommand>
+```
+
+### Help
+
+```shell
+$ forge --help
+$ anvil --help
+$ cast --help
+```

README.md

@@ -38,6 +38,8 @@ For further details on methods, hashes and availability please refer to [PRNG Pr
 
 This project is set up using the Hardhat development environment. To get started, please follow this [test setup guide](./TEST_SETUP.md).
 
+For using this project as a library in a Foundry project see [Foundry Testing](FOUNDRY_TESTING.md)
+
 ## Support
 
 If you have a question on how to use the product, please see our
@@ -63,4 +65,3 @@ to [[email protected]](mailto:[email protected]).
 ## Smart contracts - testing
 
 [Smart contracts tests - documentation](https://raw.githubusercontent.com/hashgraph/hedera-smart-contracts/main/test/README.md)
-

contracts/base/NoDelegateCall.sol

@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: Apache-2.0
+pragma solidity >=0.8.0;
+
+import "../libraries/Constants.sol";
+
+/// @title Prevents delegatecall to a contract
+/// @notice Base contract that provides a modifier for preventing delegatecall to methods in a child contract
+abstract contract NoDelegateCall is Constants {
+    /// @dev The original address of this contract
+    address private immutable original;
+
+    /// @dev slightly modified as in context of constructor address(this) is the address of the deployed contract and not the etched contract address
+    ///      hence _original allows passing the address to which a contract is etched to; for normal uses pass ADDRESS_ZERO
+    constructor(address _original) {
+        // Immutables are computed in the init code of the contract, and then inlined into the deployed bytecode.
+        // In other words, this variable won't change when it's checked at runtime.
+        original = _original == ADDRESS_ZERO ? address(this) : _original;
+    }
+
+    /// @dev Private method is used instead of inlining into modifier because modifiers are copied into each method,
+    ///     and the use of immutable means the address bytes are copied in every place the modifier is used.
+    function checkNotDelegateCall() private view {
+        require(address(this) == original, "NO_DELEGATECALL");
+    }
+
+    /// @notice Prevents delegatecall into the modified method
+    modifier noDelegateCall() {
+        checkNotDelegateCall();
+        _;
+    }
+}

contracts/libraries/Constants.sol

@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: Apache-2.0
+pragma solidity ^0.8.9;
+
+abstract contract Constants {
+  address internal constant HTS_PRECOMPILE = address(0x167);
+  address internal constant EXCHANGE_RATE_PRECOMPILE = address(0x168);
+  address internal constant UTIL_PRECOMPILE = address(0x168);
+
+  address internal constant ADDRESS_ZERO = address(0);
+}

foundry.toml

@@ -0,0 +1,12 @@
+[profile.default]
+src = 'contracts'
+out = 'out'
+libs = ['node_modules', 'lib']
+test = 'test/foundry'
+cache_path  = 'forge-cache'
+remappings = [
+    '@openzeppelin/=node_modules/@openzeppelin/',
+    'hardhat/=node_modules/hardhat/',
+]
+
+# See more config options https://github.com/foundry-rs/foundry/tree/master/config

hardhat.config.js

@@ -1,6 +1,7 @@
 require('@nomicfoundation/hardhat-chai-matchers')
 require('@nomiclabs/hardhat-ethers')
 require('@openzeppelin/hardhat-upgrades')
+require('@nomicfoundation/hardhat-foundry');
 const {
   OPERATOR_ID_A,
   OPERATOR_KEY_A,

package.json

@@ -16,14 +16,28 @@
     "url": "https://github.com/hashgraph/hedera-smart-contracts/issues"
   },
   "homepage": "https://github.com/hashgraph/hedera-smart-contracts#readme",
+  "scripts": {
+    "forge:build": "forge build",
+    "forge:test": "forge test",
+    "forge:coverage": "forge coverage",
+    "forge:coverage:report": "forge coverage --report lcov",
+    "forge:coverage:html": "forge coverage --report lcov && genhtml lcov.info --branch-coverage --output-dir coverage",
+    "hh:compile": "hardhat compile",
+    "hh:test": "hardhat test",
+    "hedera:start": "npx @hashgraph/hedera-local start --limits=false --dev=true --balance=10000000",
+    "hedera:stop": "npx @hashgraph/hedera-local stop",
+    "prepare": "husky install"
+  },
   "devDependencies": {
     "@hashgraph/hedera-local": "2.13.0",
     "@hashgraph/sdk": "^2.25.0",
     "@nomicfoundation/hardhat-chai-matchers": "^1.0.6",
+    "@nomicfoundation/hardhat-foundry": "^1.1.1",
     "@openzeppelin/contracts": "^4.9.3",
     "@openzeppelin/contracts-upgradeable": "^4.9.3",
     "@openzeppelin/hardhat-upgrades": "^1.22.1",
-    "hardhat": "^2.14.0",
+    "hardhat": "^2.17.2",
+    "husky": "^8.0.0",
     "mocha-junit-reporter": "^2.2.0",
     "mocha-multi-reporters": "^1.5.1",
     "prettier": "3.0.0"
@@ -33,4 +47,3 @@
     "dotenv": "^16.3.1"
   }
 }
-

remappings.txt

@@ -0,0 +1,2 @@
+ds-test/=lib/forge-std/lib/ds-test/src/
+forge-std/=lib/forge-std/src/

test/foundry/ExchangeRatePrecompileMock.t.sol

@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: Apache-2.0
+pragma solidity ^0.8.9;
+
+import './utils/ExchangeRateUtils.sol';
+
+contract ExchangeRatePrecompileMockTest is ExchangeRateUtils {
+
+    // setUp is executed before each and every test function
+    function setUp() public {
+        _setUpExchangeRatePrecompileMock();
+        _setUpAccounts();
+    }
+
+    function test_CanCorrectlyConvertTinycentsToTinybars() public {
+        uint256 tinycents = 1e8;
+        uint256 tinybars = _doConvertTinycentsToTinybars(tinycents);
+        assertEq(tinybars, 1e7, "expected 1 cent to equal 1e7 tinybar(0.1 HBAR) at $0.1/HBAR");
+    }
+
+    function test_CanCorrectlyConvertTinybarsToTinyCents() public {
+        uint256 tinybars = 1e8;
+        uint256 tinycents = _doConvertTinybarsToTinycents(tinybars);
+        assertEq(tinycents, 1e9, "expected 1 HBAR to equal 10 cents(1e9 tinycents) at $0.1/HBAR");
+    }
+
+}
+
+// forge test --match-contract ExchangeRatePrecompileMockTest -vv