Optimism L2 - token [Hardhat - v2]

.github/workflows/changelog.yml

@@ -0,0 +1,27 @@
+#
+# This action checks PRs to see if any CHANGELOG* files were updated.
+# If none were, it will add a message to the PR asking if it would make sense to do so.
+#
+name: Changelog
+
+on: pull_request
+
+jobs:
+  changelog:
+    name: Changelog checker
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check for changed files
+        id: changedfiles
+        uses: futuratrepadeira/changed-files@186b5b30b1f5e44ed655a59652746c3ce00d53ef # Version v3.1.1
+        with:
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
+          pattern: '^CHANGELOG.*$'
+      - name: Make a comment
+        uses: unsplash/comment-on-pr@d1a1d5dd1eb1bb657a01f4d92dd5e4d5bb7857d3 # Version v1.2.0
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        if: contains(steps.changedfiles.outputs.files_updated, 'CHANGELOG') != true && contains(steps.changedfiles.outputs.files_created, 'CHANGELOG') != true
+        with:
+          msg: "I see that you haven't updated any CHANGELOG files. Would it make sense to do so?"
+          check_for_duplicate_msg: false

.github/workflows/main.yml

@@ -0,0 +1,39 @@
+name: Main
+
+on:
+  push:
+    branches:
+      - master
+  pull_request: ~
+
+jobs:
+  run-basic-checks:
+    name: Run linters and unit tests
+    runs-on: [self-hosted]
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v2
+        with:
+          node-version: '14.x'
+      - run: npm install -g yarn
+      - run: yarn install
+      - run: yarn setup
+      - run: yarn lint
+      - run: yarn test
+  run-integration:
+    name: Setup and run integration tests
+    needs: [run-basic-checks]
+    runs-on: [self-hosted]
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v2
+        with:
+          node-version: '14.x'
+      - run: npm install -g yarn
+      - run: yarn install
+      - run: yarn setup
+      - name: Setup Optimism L2 network
+        run: yarn script:oe:up
+      - run: yarn test --network optimism
+      - name: Tear down Optimism L2 network
+        run: yarn script:oe:clean

.gitignore

@@ -8,3 +8,6 @@ coverage.json
 
 # Misc
 .DS_STORE
+
+# Optimism monorepo used for integration tests
+/optimism

.tool-versions

@@ -0,0 +1,2 @@
+node 14.16.0
+yarn 1.22.4

CHANGELOG.md

@@ -0,0 +1,36 @@
+# Changelog LinkToken
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/), and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased] - Apr 2021
+
+### Added
+
+- Access controlled mintable & burnable LinkToken, for use on sidechains and L2 networks.
+- Added versioning to v0.6 & v0.7 contracts
+
+### Changed
+
+- Migrated to Hardhat and Waffle
+- Changed LinkToken v0.6 name from 'ChainLink Token' to 'Chainlink Token'
+
+### Fixed
+
+### Removed
+
+- Truffle framework and tests dependencies
+
+## [1.1.0] - Mar 2021
+
+Initial @chainlink/token release!
+
+### Added
+
+- Solidity 0.6 support
+- Simple token swapping contract
+
+## [1.0.6] - Sep 2018
+
+Initial link_token release!

README.md

@@ -1,41 +1,73 @@
-# LINK Token Contracts [![Build Status](https://travis-ci.org/smartcontractkit/LinkToken.svg?branch=master)](https://travis-ci.org/smartcontractkit/LinkToken)
+# LINK Token Contracts
 
 The LINK token is an [EIP20](https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20-token-standard.md) token with additional [ERC677](https://github.com/ethereum/EIPs/issues/677) functionality.
 
 The total supply of the token is 1,000,000,000, and each token is divisible up to 18 decimal places.
 
 To prevent accidental burns, the token does not allow transfers to the contract itself and to 0x0.
 
-Security audit for [v0.4 version of the contracts](./contracts/v0.4/) is available [here](https://gist.github.com/Arachnid/4aa88041bd6e34835b8c0fd051245e79).
+Security audit for [0.4 version of the contracts](./contracts/v0.4/) is available [here](https://gist.github.com/Arachnid/4aa88041bd6e34835b8c0fd051245e79).
 
 ## Details
 
 - Deployments:
-  - Ethereum Mainnet [LinkToken v0.4](./flat/v0.4/LinkToken.sol): [0x514910771AF9Ca656af840dff83E8264EcF986CA](https://etherscan.io/address/0x514910771af9ca656af840dff83e8264ecf986ca)
+  - Ethereum Mainnet [LinkToken 0.4](./flat/v0.4/LinkToken.sol): [0x514910771AF9Ca656af840dff83E8264EcF986CA](https://etherscan.io/address/0x514910771af9ca656af840dff83e8264ecf986ca)
 - Decimals: 18
 - Name: ChainLink Token
 - Symbol: LINK
 
-## Installation
+## Setup
 
-The project contains [v0.4 contracts](./contracts/v0.4/) that were used for LINK Ethereum Mainnet deployment in 2017. For deployments moving forward, we use the updated [v0.6 contracts](./contracts/v0.6/) which use a more recent version of solc and the OpenZeppelin token standards. These updates include a minor ABI change around approval/allowance naming.
+The project contains [0.4 contracts](./contracts/v0.4/) that were used for LINK Ethereum Mainnet deployment in 2017. For deployments moving forward, we use the updated [0.6 contracts](./contracts/v0.6/) which use a more recent version of solc and the OpenZeppelin token standards. These updates include a minor ABI change around approval/allowance naming.
 
 ```bash
 yarn install
 ```
 
-## Testing
-
 Setup contracts:
 
 ```bash
 yarn setup
 ```
 
+This will compile all versions of the contracts.
+
+## Testing
+
 Run tests:
 
 ```bash
 yarn test
 ```
 
-This will test both v0.4 and v0.6 versions of the contracts.
+This will run unit tests for all versions of the contracts.
+
+## Integration testing
+
+Integration tests are currently setup for Optimism contracts, and to run them make sure you have a local network running first.
+
+The network can be started using a helpful script, which will clone the [Optimism monorepo](https://github.com/ethereum-optimism/optimism), build the :
+
+```bash
+yarn script:oe:up
+```
+
+Run tests:
+
+```bash
+yarn test --network optimism
+```
+
+This will run unit tests for all versions of the contracts, plus supported integration tests against the local L1 & L2 networks.
+
+The network can be stopped using another script:
+
+```bash
+yarn script:oe:down
+```
+
+Or use the clean script, which will also delete all the images:
+
+```bash
+yarn script:oe:clean
+```

contracts/v0.6/ERC677Token.sol

@@ -1,48 +1,58 @@
 // SPDX-License-Identifier: MIT
 pragma solidity >0.6.0 <0.8.0;
 
-import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
+import "../vendor/@openzeppelin/contracts/3.4.1/contracts/token/ERC20/ERC20.sol";
 import "./token/ERC677.sol";
 import "./token/ERC677Receiver.sol";
 
 abstract contract ERC677Token is ERC20, ERC677 {
   /**
    * @dev transfer token to a contract address with additional data if the recipient is a contact.
-   * @param _to The address to transfer to.
-   * @param _value The amount to be transferred.
-   * @param _data The extra data to be passed to the receiving contract.
+   * @param to The address to transfer to.
+   * @param value The amount to be transferred.
+   * @param data The extra data to be passed to the receiving contract.
    */
-  function transferAndCall(address _to, uint _value, bytes memory _data)
+  function transferAndCall(
+    address to,
+    uint value,
+    bytes memory data
+  )
     public
     override
     virtual
     returns (bool success)
   {
-    super.transfer(_to, _value);
-    emit Transfer(msg.sender, _to, _value, _data);
-    if (isContract(_to)) {
-      contractFallback(_to, _value, _data);
+    super.transfer(to, value);
+    emit Transfer(msg.sender, to, value, data);
+    if (isContract(to)) {
+      contractFallback(to, value, data);
     }
     return true;
   }
 
 
   // PRIVATE
 
-  function contractFallback(address _to, uint _value, bytes memory _data)
+  function contractFallback(
+    address to,
+    uint value,
+    bytes memory data
+  )
     private
   {
-    ERC677Receiver receiver = ERC677Receiver(_to);
-    receiver.onTokenTransfer(msg.sender, _value, _data);
+    ERC677Receiver receiver = ERC677Receiver(to);
+    receiver.onTokenTransfer(msg.sender, value, data);
   }
 
-  function isContract(address _addr)
+  function isContract(
+    address addr
+  )
     private
     view
     returns (bool hasCode)
   {
     uint length;
-    assembly { length := extcodesize(_addr) }
+    assembly { length := extcodesize(addr) }
     return length > 0;
   }
 }

contracts/v0.6/LinkToken.sol

@@ -3,18 +3,40 @@ pragma solidity >0.6.0 <0.8.0;
 
 import "./token/LinkERC20.sol";
 import "./ERC677Token.sol";
+import "./TypeAndVersionInterface.sol";
 
-contract LinkToken is LinkERC20, ERC677Token {
+/// @dev LinkToken, an ERC20/ERC677 Chainlink token with 1 billion supply
+contract LinkToken is TypeAndVersionInterface, LinkERC20, ERC677Token {
   uint private constant TOTAL_SUPPLY = 10**27;
-  string private constant NAME = 'ChainLink Token';
+  string private constant NAME = 'Chainlink Token';
   string private constant SYMBOL = 'LINK';
 
-  constructor() ERC20(NAME, SYMBOL)
+  constructor()
+    ERC20(NAME, SYMBOL)
     public
   {
     _onCreate();
   }
 
+  /**
+   * @notice versions:
+   *
+   * - LinkToken 0.0.3: added versioning, update name
+   * - LinkToken 0.0.2: upgraded to solc 0.6
+   * - LinkToken 0.0.1: initial release solc 0.4
+   *
+   * @inheritdoc TypeAndVersionInterface
+   */
+  function typeAndVersion()
+    external
+    pure
+    override
+    virtual
+    returns (string memory)
+  {
+    return "LinkToken 0.0.3";
+  }
+
   /**
    * @dev Hook that is called when this contract is created.
    * Useful to override constructor behaviour in child contracts (e.g., LINK bridge tokens).
@@ -31,7 +53,11 @@ contract LinkToken is LinkERC20, ERC677Token {
    * @dev Check if recepient is a valid address before transfer
    * @inheritdoc ERC20
    */
-  function _transfer(address sender, address recipient, uint256 amount)
+  function _transfer(
+    address sender,
+    address recipient,
+    uint256 amount
+  )
     internal
     override
     virtual
@@ -44,7 +70,11 @@ contract LinkToken is LinkERC20, ERC677Token {
    * @dev Check if spender is a valid address before approval
    * @inheritdoc ERC20
    */
-  function _approve(address owner, address spender, uint256 amount)
+  function _approve(
+    address owner,
+    address spender,
+    uint256 amount
+  )
     internal
     override
     virtual
@@ -53,13 +83,16 @@ contract LinkToken is LinkERC20, ERC677Token {
     super._approve(owner, spender, amount);
   }
 
-
-  // MODIFIERS
-
-  modifier validAddress(address _recipient)
+  /**
+   * @dev Check if recipient is valid (not this contract address)
+   * @param recipient the account we transfer/approve to
+   */
+  modifier validAddress(
+    address recipient
+  )
     virtual
   {
-    require(_recipient != address(this), "LinkToken: transfer/approve to this contract address");
+    require(recipient != address(this), "LinkToken: transfer/approve to this contract address");
     _;
   }
 }