Merge pull request #441 from scaffold-eth/challenge-zk-voting-foundry

Foundry support - Challenge-zk-voting-foundry

Author: rin-st

README.md

@@ -47,6 +47,7 @@ Before you begin, you need to install the following tools:
 - [Node (>= v20.18.3)](https://nodejs.org/en/download/)
 - [Yarn (v2+)](https://yarnpkg.com/getting-started/install)
 - [Git](https://git-scm.com/downloads)
+- [Foundry](https://book.getfoundry.sh/getting-started/installation) (If you chose Foundry as solidity framework)
 - [Nargo](https://noir-lang.org/docs/getting_started/quick_start#installation) (v1.0.0-beta.3)
 - [bb](https://barretenberg.aztec.network/docs/getting_started/) (v0.82.2)
 
@@ -88,10 +89,12 @@ If you are using vscode you may want to install the [Noir Language Support](http
 Then download the challenge to your computer and install dependencies by running:
 
 ```sh
-npx create-eth@2.0.13 -e scaffold-eth/se-2-challenges:challenge-zk-voting challenge-zk-voting
+npx create-eth@2.0.18 -e scaffold-eth/se-2-challenges:challenge-zk-voting challenge-zk-voting
 cd challenge-zk-voting
 ```
 
+> When prompted, choose your preferred solidity framework (Hardhat or Foundry)
+
 In the same terminal, start your local network (a blockchain emulator in your computer):
 
 ```sh
@@ -163,8 +166,23 @@ Our contract will support three main functions:
 
 🔍 Next, switch to the **`Debug Contracts`** page. For now, you should see just one contract there — **`Voting`**.
 
+<Tabs>
+<Tab label="Hardhat">
+
+**Hardhat**
+
 📁 The contract lives in **`packages/hardhat/contracts/Voting.sol`**
 
+</Tab>
+<Tab label="Foundry">
+
+**Foundry**
+
+📁 The contract lives in **`packages/foundry/contracts/Voting.sol`**
+
+</Tab>
+</Tabs>
+
 🔍 Open it up and check out the placeholder functions. Each of them represents a key piece of the voting logic.
 If you can already explain what they’re supposed to do, you’re ahead of the game! 😎
 
@@ -364,23 +382,58 @@ Scroll down to the functions **`getVotingData()`** and **`getVoterData(address _
 
 Then run:
 
+<Tabs>
+<Tab label="Hardhat">
+
+**Hardhat**
+
 ```sh
 yarn test --grep "Checkpoint2"
 ```
 
+</Tab>
+<Tab label="Foundry">
+
+**Foundry**
+
+```sh
+yarn test --match-test "Checkpoint2"
+```
+
+</Tab>
+</Tabs>
+
 ### 🚀 Tests Passed? You’re Almost There!
 
 Great job! If your tests are passing, you’re just one step away from deployment! 🚀
 
 Before deploying, make one important change:
 
+<Tabs>
+<Tab label="Hardhat">
+
+**Hardhat**
+
 1. Open **`00_deploy_your_voting_contract.ts`**
 2. Set your address as the `ownerAddress`
 3. Uncomment deployment of both `poseidon3` and `leanIMT`
 4. Set LeanIMT library address (`leanIMT.address`) at line 62
 
 > 💡 **Poseidon3** is the hash function we use. More on that later.
 
+</Tab>
+<Tab label="Foundry">
+
+**Foundry**
+
+1. Open **`DeployVoting.s.sol`**
+2. Set your address as the `ownerAddress`
+
+> 💡 In Foundry, library linking is handled automatically at compile time — no need to deploy PoseidonT3 or LeanIMT separately.
+
+</Tab>
+</Tabs>
+
 Once that’s done, you’re ready to deploy! 🔗
 
 Run `yarn deploy` and check out the front-end
@@ -952,12 +1005,31 @@ You’ve built the circuit, created the verifier contract — now it’s time to
 
 ### 🔹 Step 1: Bring in the Verifier Contract
 
+<Tabs>
+<Tab label="Hardhat">
+
+**Hardhat**
+
 1. Replace the placeholder verifier contract **`Verifier.sol`** in **`packages/hardhat/contracts`** with the newly generated contract located in **`packages/circuits/target`**.
 2. Open **`00_deploy_your_voting_contract.ts`** and:
    - Uncomment the verifier deployment
    - Comment out the `verifierAddress`
    - Update the `args` to match your setup
 
+</Tab>
+<Tab label="Foundry">
+
+**Foundry**
+
+1. Replace the placeholder verifier contract **`Verifier.sol`** in **`packages/foundry/contracts`** with the newly generated contract located in **`packages/circuits/target`**.
+2. Open **`DeployVoting.s.sol`** and:
+   - Uncomment the verifier deployment
+   - Comment out the placeholder `verifierAddress`
+   - Update the constructor call to match your setup
+
+</Tab>
+</Tabs>
+
 3. In **`Voting.sol`**:
    - At the top, import the verifier contract (just uncomment the existing line)
    - In the constructor, initialize the verifier and store it in a variable called `i_verifier`
@@ -1116,10 +1188,27 @@ function vote(bytes memory _proof, bytes32 _nullifierHash, bytes32 _root, bytes3
 
 Once implemented, run your tests to make sure everything works:
 
+<Tabs>
+<Tab label="Hardhat">
+
+**Hardhat**
+
 ```sh
 yarn test --grep "Checkpoint6"
 ```
 
+</Tab>
+<Tab label="Foundry">
+
+**Foundry**
+
+```sh
+yarn test --match-test "Checkpoint6"
+```
+
+</Tab>
+</Tabs>
+
 ### **✅ Tests Passed? You're So Close!**
 
 If your tests are green, congratulations — you’ve just completed the **core `Voting.sol` contract!** 🎉
@@ -1813,10 +1902,27 @@ For **production-grade apps**, you should generate your own API keys to avoid hi
 
 Configure your keys here:
 
+<Tabs>
+<Tab label="Hardhat">
+
+**Hardhat**
+
 - 🔷 **`ALCHEMY_API_KEY`** in `packages/hardhat/.env` and `packages/nextjs/.env.local` → [Get key from Alchemy](https://dashboard.alchemy.com/)
 - 🔑 **`NEXT_PUBLIC_PIMLICO_API_KEY`** in `packages/nextjs/.env.local` → [Get key from Pimlico](https://dashboard.pimlico.io/)
 - 📃 **`ETHERSCAN_API_KEY`** in `packages/hardhat/.env` → [Get key from Etherscan](https://etherscan.io/myapikey)
 
+</Tab>
+<Tab label="Foundry">
+
+**Foundry**
+
+- 🔷 **`ALCHEMY_API_KEY`** in `packages/foundry/.env` and `packages/nextjs/.env.local` → [Get key from Alchemy](https://dashboard.alchemy.com/)
+- 🔑 **`NEXT_PUBLIC_PIMLICO_API_KEY`** in `packages/nextjs/.env.local` → [Get key from Pimlico](https://dashboard.pimlico.io/)
+- 📃 **`ETHERSCAN_API_KEY`** in `packages/foundry/.env` → [Get key from Etherscan](https://etherscan.io/myapikey)
+
+</Tab>
+</Tabs>
+
 > 💬 Hint: Store environment variables for **Next.js** in Vercel/system env config for live apps, and use `.env.local` for local testing.
 
 ### Deploying Your Smart Contracts
@@ -1827,11 +1933,28 @@ Configure your keys here:
 
 ⛽️ You will need to send ETH to your deployer address with your wallet, or obtain it from a public faucet of your chosen network.
 
-> 🚨 Don’t forget to set the owner address inside the 00_deploy_your_voting_contract.ts .
+<Tabs>
+<Tab label="Hardhat">
+
+**Hardhat**
+
+> 🚨 Don't forget to set the owner address inside the `00_deploy_your_voting_contract.ts`.
+
+🚀 Run `yarn deploy --network sepolia` to deploy your smart contract to Sepolia.
+
+> 💬 Hint: You can set the defaultNetwork in hardhat.config.ts to sepolia OR you can yarn deploy --network sepolia.
 
-🚀 Run `yarn deploy --network sepolia` to deploy your smart contract to Sepolia.
+</Tab>
+<Tab label="Foundry">
 
-> 💬 Hint: You can set the defaultNetwork in hardhat.config.ts to sepolia OR you can yarn deploy --network sepolia.
+**Foundry**
+
+> 🚨 Don't forget to set the owner address inside the `DeployVoting.s.sol`.
+
+🚀 Run `yarn deploy --network sepolia` to deploy your smart contract to Sepolia.
+
+</Tab>
+</Tabs>
 
 💻 Inside `scaffold.config.ts` change the `targetNetwork` to `chains.sepolia`. View your front-end at http://localhost:3000 and verify you see the correct network Sepolia.
 
@@ -1953,3 +2076,15 @@ But this is just the beginning. The same **commitment + nullifier** pattern that
 This challenge is your **entry point into a new design space.** 💥
 
 **What will you build with Noir and ZK circuits? 🧪✨**
+
+## AI-Guided Learning Mode (Optional)
+
+This challenge supports an interactive AI learning mode. Instead of reading instructions above, you can let an AI guide you step by step.
+
+**How to use:**
+1. Open a terminal in the project root
+2. Run `/start` to begin the guided challenge
+3. The AI will teach concepts and give you coding tasks
+4. Say `check` to validate your code, `hint` for help, or `/skip` to skip a task
+
+> Note: If you chose Foundry as your framework, the screenshots in this README show the Hardhat version, but the contract logic and challenge flow are identical.

extension/.ai/CHALLENGE.yaml

@@ -5,7 +5,9 @@ difficulty: "advanced"
 estimated_time: "6 - 16 hours"
 
 setup:
-  file: "packages/hardhat/contracts/Voting.sol"
+  file:
+    hardhat: "packages/hardhat/contracts/Voting.sol"
+    foundry: "packages/foundry/contracts/Voting.sol"
 
 welcome_message: |
   Welcome to the ZK Voting Challenge!
@@ -169,8 +171,12 @@ checkpoints:
         4. Check `getVotingData()` — you should see Merkle tree data (size, depth, root).
 
         Say **"check"** when you're ready!
-      file: "packages/hardhat/contracts/Voting.sol"
-      test: "yarn test --grep 'Checkpoint2'"
+      file:
+        hardhat: "packages/hardhat/contracts/Voting.sol"
+        foundry: "packages/foundry/contracts/Voting.sol"
+      test:
+        hardhat: "yarn test --grep 'Checkpoint2'"
+        foundry: "yarn test --match-test 'Checkpoint2'"
       hints:
         - "The two guard checks use existing state: `s_voters` (allowlist) and the new `s_hasRegistered` mapping."
         - |
@@ -719,8 +725,12 @@ checkpoints:
         4. Head to the **Voting** page — the full voting flow is now functional on the contract side!
 
         Say **"check"** when you're ready!
-      file: "packages/hardhat/contracts/Voting.sol"
-      test: "yarn test --grep 'Checkpoint6'"
+      file:
+        hardhat: "packages/hardhat/contracts/Voting.sol"
+        foundry: "packages/foundry/contracts/Voting.sol"
+      test:
+        hardhat: "yarn test --grep 'Checkpoint6'"
+        foundry: "yarn test --match-test 'Checkpoint6'"
       hints:
         - "Don't forget the setup steps: replace Verifier.sol, update the deploy script, uncomment the import, add the two state variables, and initialize `i_verifier` in the constructor."
         - |

extension/.ai/instructions/skip-content.md

@@ -14,7 +14,10 @@ Read `.ai/CHALLENGE.yaml` and find the current checkpoint by its ID.
 
 - If the current checkpoint does NOT have a `task` field, tell the user:
   "This checkpoint doesn't have a coding task to skip. Say 'hint' if you need help with the current question."
-- If it has a `task` field, continue to Step 3
+- If it has a `task` field, continue to Step 2b
+
+### Step 2b: Resolve Framework-Specific Fields
+CHALLENGE.yaml `file:` and `test:` fields contain framework-specific values (e.g. `hardhat:` and `foundry:`). Detect which framework this project uses by checking which directory exists (`packages/hardhat/` vs `packages/foundry/`). Use the matching key for all `file:` and `test:` lookups throughout the skip flow.
 
 ### Step 3: Show the Solution
 Display the solution from `task.solution` with an explanation:
@@ -38,7 +41,7 @@ Read the current contract file (`task.file`) and apply the solution code:
 - Be careful to place code in the correct sections of the contract
 
 ### Step 5: Run Tests
-Execute the `task.test` command (e.g., `yarn test --grep "Checkpoint1"`) to verify the solution works.
+Execute the `task.test` command (resolved for the detected framework, e.g., `yarn test --grep "Checkpoint1"` for Hardhat or `yarn test --match-test "Checkpoint1"` for Foundry) to verify the solution works.
 - If tests pass: continue to Step 6
 - If tests fail: debug and fix (this shouldn't happen with correct solutions)
 

extension/.ai/instructions/start-content.md

@@ -33,6 +33,9 @@ Read the file `.ai/CHALLENGE.yaml` to understand:
 - All checkpoints with their context, questions, tasks, and code unlocks
 - Whether each checkpoint is a **concept checkpoint** (has `unlocks`) or a **code-writing checkpoint** (has `task`)
 
+### Step 1b: Resolve Framework-Specific Fields
+CHALLENGE.yaml `file:` and `test:` fields contain framework-specific values (e.g. `hardhat:` and `foundry:`). Detect which framework this project uses by checking which directory exists (`packages/hardhat/` vs `packages/foundry/`). Use the matching key for all `file:` and `test:` lookups throughout the challenge.
+
 ### Step 2: Apply Setup (if applicable)
 Check if CHALLENGE.yaml has a `setup.template` field:
 
@@ -274,7 +277,7 @@ The user will respond with one of:
 
 ### Phase 5: Validate with Tests
 
-Run the test command from `task.test` (e.g., `yarn test --grep "Checkpoint1"`).
+Run the test command from `task.test` (resolved for the detected framework, e.g., `yarn test --grep "Checkpoint1"` for Hardhat or `yarn test --match-test "Checkpoint1"` for Foundry).
 
 **If ALL tests pass:**
 ```