chore: project boilerplate

.env.example

@@ -1,11 +1,3 @@
 export API_KEY_ALCHEMY="YOUR_API_KEY_ALCHEMY"
-export API_KEY_ARBISCAN="YOUR_API_KEY_ARBISCAN"
-export API_KEY_BSCSCAN="YOUR_API_KEY_BSCSCAN"
 export API_KEY_ETHERSCAN="YOUR_API_KEY_ETHERSCAN"
-export API_KEY_GNOSISSCAN="YOUR_API_KEY_GNOSISSCAN"
-export API_KEY_INFURA="YOUR_API_KEY_INFURA"
-export API_KEY_OPTIMISTIC_ETHERSCAN="YOUR_API_KEY_OPTIMISTIC_ETHERSCAN"
-export API_KEY_POLYGONSCAN="YOUR_API_KEY_POLYGONSCAN"
-export API_KEY_SNOWTRACE="YOUR_API_KEY_SNOWTRACE"
-export MNEMONIC="YOUR_MNEMONIC"
 export FOUNDRY_PROFILE="default"

.github/workflows/ci.yml

@@ -21,14 +21,17 @@ jobs:
       - name: "Install Foundry"
         uses: "foundry-rs/foundry-toolchain@v1"
 
-      - name: "Install Bun"
-        uses: "oven-sh/setup-bun@v1"
+      - name: Use Node.js 21
+        uses: actions/setup-node@v3
+        with:
+          node-version: 21
+          cache: 'npm'
 
       - name: "Install the Node.js dependencies"
-        run: "bun install"
+        run: "npm install"
 
       - name: "Lint the code"
-        run: "bun run lint"
+        run: "npm run lint"
 
       - name: "Add lint summary"
         run: |
@@ -44,11 +47,14 @@ jobs:
       - name: "Install Foundry"
         uses: "foundry-rs/foundry-toolchain@v1"
 
-      - name: "Install Bun"
-        uses: "oven-sh/setup-bun@v1"
+      - name: Use Node.js 21
+        uses: actions/setup-node@v3
+        with:
+          node-version: 21
+          cache: 'npm'
 
       - name: "Install the Node.js dependencies"
-        run: "bun install"
+        run: "npm install"
 
       - name: "Build the contracts and print their size"
         run: "forge build --sizes"
@@ -68,11 +74,14 @@ jobs:
       - name: "Install Foundry"
         uses: "foundry-rs/foundry-toolchain@v1"
 
-      - name: "Install Bun"
-        uses: "oven-sh/setup-bun@v1"
+      - name: Use Node.js 21
+        uses: actions/setup-node@v3
+        with:
+          node-version: 21
+          cache: 'npm'
 
       - name: "Install the Node.js dependencies"
-        run: "bun install"
+        run: "npm install"
 
       - name: "Show the Foundry config"
         run: "forge config"

.prettierignore

@@ -10,7 +10,6 @@ out
 *.log
 .DS_Store
 .pnp.*
-bun.lockb
 lcov.info
 package-lock.json
 pnpm-lock.yaml

.vscode/settings.json

@@ -1,9 +1,10 @@
 {
   "[solidity]": {
-    "editor.defaultFormatter": "NomicFoundation.hardhat-solidity"
+    "editor.defaultFormatter": "JuanBlanco.solidity"
   },
   "[toml]": {
     "editor.defaultFormatter": "tamasfe.even-better-toml"
   },
-  "solidity.formatter": "forge"
-}
+  "solidity.formatter": "forge",
+  "solidity.compileUsingRemoteVersion": "v0.8.25+commit.b61c2a91"
+}

README.md

@@ -1,205 +1,96 @@
-# Foundry Template [![Open in Gitpod][gitpod-badge]][gitpod] [![Github Actions][gha-badge]][gha] [![Foundry][foundry-badge]][foundry] [![License: MIT][license-badge]][license]
+# Token Vendor Machine Challenge
 
-[gitpod]: https://gitpod.io/#https://github.com/PaulRBerg/foundry-template
-[gitpod-badge]: https://img.shields.io/badge/Gitpod-Open%20in%20Gitpod-FFB45B?logo=gitpod
-[gha]: https://github.com/PaulRBerg/foundry-template/actions
-[gha-badge]: https://github.com/PaulRBerg/foundry-template/actions/workflows/ci.yml/badge.svg
-[foundry]: https://getfoundry.sh/
-[foundry-badge]: https://img.shields.io/badge/Built%20with-Foundry-FFDB1C.svg
-[license]: https://opensource.org/licenses/MIT
-[license-badge]: https://img.shields.io/badge/License-MIT-blue.svg
+This project is designed to test your skills in smart contract development using Solidity.
 
-A Foundry-based template for developing Solidity smart contracts, with sensible defaults.
+## Project Overview
 
-## What's Inside
+You are tasked with implementing a token vendor machine that allows users to buy and sell tokens. The project consists of two main contracts:
 
-- [Forge](https://github.com/foundry-rs/foundry/blob/master/forge): compile, test, fuzz, format, and deploy smart
-  contracts
-- [Forge Std](https://github.com/foundry-rs/forge-std): collection of helpful contracts and utilities for testing
-- [Prettier](https://github.com/prettier/prettier): code formatter for non-Solidity files
-- [Solhint](https://github.com/protofire/solhint): linter for Solidity code
+1. `BlockfulToken.sol`: An ERC20 token contract
+2. `TokenVendor.sol`: A vendor contract for buying and selling tokens
 
 ## Getting Started
 
-Click the [`Use this template`](https://github.com/PaulRBerg/foundry-template/generate) button at the top of the page to
-create a new repository with this repo as the initial state.
+To get started with this project, follow these steps:
 
-Or, if you prefer to install the template manually:
+1. Clone this repository.
+2. Run `npm install` to install Node.js dependencies
 
-```sh
-$ mkdir my-project
-$ cd my-project
-$ forge init --template PaulRBerg/foundry-template
-$ bun install # install Solhint, Prettier, and other Node.js deps
-```
-
-If this is your first time with Foundry, check out the
-[installation](https://github.com/foundry-rs/foundry#installation) instructions.
-
-## Features
-
-This template builds upon the frameworks and libraries mentioned above, so please consult their respective documentation
-for details about their specific features.
-
-For example, if you're interested in exploring Foundry in more detail, you should look at the
-[Foundry Book](https://book.getfoundry.sh/). In particular, you may be interested in reading the
-[Writing Tests](https://book.getfoundry.sh/forge/writing-tests.html) tutorial.
-
-### Sensible Defaults
-
-This template comes with a set of sensible default configurations for you to use. These defaults can be found in the
-following files:
-
-```text
-├── .editorconfig
-├── .gitignore
-├── .prettierignore
-├── .prettierrc.yml
-├── .solhint.json
-├── foundry.toml
-└── remappings.txt
-```
-
-### VSCode Integration
-
-This template is IDE agnostic, but for the best user experience, you may want to use it in VSCode alongside Nomic
-Foundation's [Solidity extension](https://marketplace.visualstudio.com/items?itemName=NomicFoundation.hardhat-solidity).
-
-For guidance on how to integrate a Foundry project in VSCode, please refer to this
-[guide](https://book.getfoundry.sh/config/vscode).
-
-### GitHub Actions
-
-This template comes with GitHub Actions pre-configured. Your contracts will be linted and tested on every push and pull
-request made to the `main` branch.
+## Your Tasks
 
-You can edit the CI script in [.github/workflows/ci.yml](./.github/workflows/ci.yml).
+1. Implement the `BlockfulToken` contract:
+   - It should be an ERC20 token with a name, symbol, and 18 decimals.
+   - Initial supply should be 1,000,000 tokens.
 
-## Installing Dependencies
+2. Implement the `TokenVendor` contract with the following functionality:
+   - Allow users to buy tokens with ETH (1 ETH = 100 tokens)
+   - Allow users to sell tokens back to the contract
+   - Allow the owner to withdraw ETH from the contract
+   - Implement proper access control (only owner can withdraw)
+   - Emit events for token purchases, sales, and ETH withdrawals
 
-Foundry typically uses git submodules to manage dependencies, but this template uses Node.js packages because
-[submodules don't scale](https://twitter.com/PaulRBerg/status/1736695487057531328).
+3. Complete the test file `test/TokenVendor.t.sol`:
+   - We've provided some basic "happy path" tests
+   - Implement additional tests for edge cases and potential failure scenarios
+   - Aim for at least 90% test coverage
 
-This is how to install dependencies:
+4. Update this README with:
+   - Any additional setup or testing instructions
+   - An explanation of your design decisions
+   - Any potential improvements or considerations for a real-world deployment
 
-1. Install the dependency using your preferred package manager, e.g. `bun install dependency-name`
-   - Use this syntax to install from GitHub: `bun install github:username/repo-name`
-2. Add a remapping for the dependency in [remappings.txt](./remappings.txt), e.g.
-   `dependency-name=node_modules/dependency-name`
+## Bonus Tasks
 
-Note that OpenZeppelin Contracts is pre-installed, so you can follow that as an example.
+If you complete the main tasks and want to demonstrate more advanced skills:
 
-## Writing Tests
-
-To write a new test contract, you start by importing `Test` from `forge-std`, and then you inherit it in your test
-contract. Forge Std comes with a pre-instantiated [cheatcodes](https://book.getfoundry.sh/cheatcodes/) environment
-accessible via the `vm` property. If you would like to view the logs in the terminal output, you can add the `-vvv` flag
-and use [console.log](https://book.getfoundry.sh/faq?highlight=console.log#how-do-i-use-consolelog).
-
-This template comes with an example test contract [Foo.t.sol](./test/Foo.t.sol)
+1. Implement a simple dynamic pricing mechanism (e.g., price increases as supply decreases)
+2. Add a feature to pause/unpause the contract (owner only)
+3. Implement a whitelist system for early access to token sales
 
 ## Usage
 
-This is a list of the most frequently needed commands.
+Here are some common commands you'll need:
 
 ### Build
 
-Build the contracts:
-
-```sh
-$ forge build
-```
-
-### Clean
-
-Delete the build artifacts and cache directories:
-
 ```sh
-$ forge clean
+npm run build
 ```
 
-### Compile
-
-Compile the contracts:
+### Test
 
 ```sh
-$ forge build
+npm run  test
 ```
 
 ### Coverage
 
-Get a test coverage report:
-
 ```sh
-$ forge coverage
+npm run test:coverage
 ```
 
-### Deploy
+## Evaluation Criteria
 
-Deploy to Anvil:
-
-```sh
-$ forge script script/Deploy.s.sol --broadcast --fork-url http://localhost:8545
-```
+Your submission will be evaluated based on:
 
-For this script to work, you need to have a `MNEMONIC` environment variable set to a valid
-[BIP39 mnemonic](https://iancoleman.io/bip39/).
+- Correctness of the implementation
+- Code quality and organization
+- Test coverage and quality
+- Security considerations
+- Testnet deployment
+- Documentation and comments
+- (For bonus tasks) Creativity and effectiveness of additional features
 
-For instructions on how to deploy to a testnet or mainnet, check out the
-[Solidity Scripting](https://book.getfoundry.sh/tutorials/solidity-scripting.html) tutorial.
+## Submission
 
-### Format
-
-Format the contracts:
-
-```sh
-$ forge fmt
-```
-
-### Gas Usage
-
-Get a gas report:
-
-```sh
-$ forge test --gas-report
-```
-
-### Lint
-
-Lint the contracts:
-
-```sh
-$ bun run lint
-```
-
-### Test
-
-Run the tests:
-
-```sh
-$ forge test
-```
-
-Generate test coverage and output result to the terminal:
-
-```sh
-$ bun run test:coverage
-```
-
-Generate test coverage with lcov report (you'll have to open the `./coverage/index.html` file in your browser, to do so
-simply copy paste the path):
-
-```sh
-$ bun run test:coverage:report
-```
+Please submit your completed project as a Git repository. Make sure to include:
 
-## Related Efforts
+- All source code files
+- Complete test suite
+- Updated README with your notes and explanations
 
-- [abigger87/femplate](https://github.com/abigger87/femplate)
-- [cleanunicorn/ethereum-smartcontract-template](https://github.com/cleanunicorn/ethereum-smartcontract-template)
-- [foundry-rs/forge-template](https://github.com/foundry-rs/forge-template)
-- [FrankieIsLost/forge-template](https://github.com/FrankieIsLost/forge-template)
+## Note
 
-## License
+This project uses [Foundry](https://getfoundry.sh/). If you're new to Foundry, check out the [Foundry Book](https://book.getfoundry.sh/) for detailed instructions and tutorials.
 
-This project is licensed under MIT.
+Good luck with the challenge! We're excited to see your implementation.