Foundry

Running Foundry Test Scripts

This documentation provides a step-by-step guide to setting up Foundry, configuring dependencies, and executing test scripts for integrations with Compound, Aave, and LayerBank protocols.

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1. Install Foundry

Foundry is a Rust-based Ethereum development framework providing tools like forge, cast, and anvil for compiling, deploying, and testing smart contracts.

1. Install Foundry (Linux/Mac):

curl -L https://foundry.paradigm.xyz | bash

Reload your environment:

foundryup

Verify installation:

forge --version

2. For Windows users (WSL):

Option 1: Using Windows Subsystem for Linux (WSL)

• Install WSL and Ubuntu from the Microsoft Store.

• Follow the above Linux installation steps within WSL.

Option 2: Using PowerShell Run the following command in PowerShell:

iwr -useb https://foundry.paradigm.xyz | iex

Restart the terminal and run:

foundryup

Verify installation:

forge --version

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Clone and Configure the Repository

Clone the repository and enter its directory:

git clone https://github.com/polystream-core/polystream-contracts
cd polystream-contracts

Install Dependencies

Foundry requires external libraries (Compound, Aave, LayerBank). Install them using forge install:

forge install \
    foundry-rs/forge-std \
    account-abstraction/contracts \
    aave/aave-v3-core \
    layerbank/layerbank-core \
    openzeppelin/openzeppelin-contracts \
    account-abstraction/contracts

This command ensures all dependencies are placed in the lib/ directory.

Configure foundry.toml

Set your foundry.toml configuration as follows:

[profile.default]
optimizer = true
optimizer_runs = 200
via_ir = true
src = 'src/'
out = 'out/'
libs = ['lib/']
remappings = [
    "@syncswapcontracts/=lib/core-contracts/contracts/",
    "@layerbank-contracts/=lib/contracts/",
    "@openzeppelin/=lib/openzeppelin-contracts/",
    "@aave/=lib/aave-v3-origin/src/",
    "@forge-std/=lib/forge-std/",
    "@account-abstraction/=lib/account-abstraction/contracts/"
]

This configuration:

• Enables IR-based compilation (via_ir = true) for optimized bytecode.

• Enables Solidity optimizer with 200 runs (optimizer = true).

• Defines remappings for external dependencies.

• Specifies src/ as the source directory and lib/ as the library directory.

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Run Local Fork with Anvil

Anvil is a fast Ethereum RPC fork provider for running local blockchain simulations.

1. Start Local Anvil Node

Run Anvil for local blockchain development:

anvil --fork-url YOUR_RPC_URL --chain-id YOUR_CHAIN_ID

Replace:

• https://your-rpc-url.com with your RPC provider.

• YOUR_CHAIN_ID with your blockchain's Chain ID (e.g., 1 for Ethereum, 534352 for Scroll).

Example for Scroll Mainnet (using Alchemy):

anvil --fork-url https://scroll-mainnet.g.alchemy.com/v2/YOUR_ALCHEMY_KEY --chain-id 534352

What This Does:

• Forks the mainnet, allowing contract interactions as if on mainnet.

• Persists the blockchain state, so transactions behave realistically.

• Runs a local RPC server (127.0.0.1:8545) for Foundry tests.

2. Run Foundry Tests

Navigate to the test directory:

cd test

Run specific tests:

forge test --fork-url http://127.0.0.1:8545 --match-path test/YOUR_TEST_SCRIPT.t.sol -vvv

Replace YOUR_TEST_SCRIPT.t.sol with the actual test file name. Example:

forge test --fork-url http://127.0.0.1:8545 --match-path test/CompoundAdapterTest.t.sol -vvv

Explanation of Flags:

• --fork-url http://127.0.0.1:8545→ Connects to the locally running Anvil fork.

• --match-path test/YOUR_TEST_SCRIPT.t.sol → Runs a specific test script.

• -vvv → Enables verbose mode (displays logs, transactions, and errors).

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Log Successful Test Runs

Use the following command to log test results and store them in a file:

forge test --fork-url http://127.0.0.1:8545 -vvv | tee test-results.log

tee test-results.log → Saves all logs to test-results.log.

Review logs by opening the file:

cat test-results.log

Example Running Test Script for Combined Vault

forge test --fork-url http://127.0.0.1:8545 --match-path test/CombinedVault.t.sol -vvv

If successful, the output will look like:

Ran 8 tests for test/CombinedVault.t.sol:CombinedVaultTest
[PASS] testEarlyWithdrawalFee() (gas: 607134)
Logs:
  User 1 USDC balance: 1000000000
  User 2 USDC balance: 1000000000
  Distributing assets to Active Protocol ID: 1
  Supplied to Protocol ID: 1 Amount: 100000000
  Initial USDC balance before withdrawal: 900000000
  Final USDC balance after withdrawal: 995000000
  Actual received: 95000000
  Expected to receive: 95000000
  Early withdrawal fee test passed

// ... other test cases

Suite result: ok. 8 passed; 0 failed; 0 skipped; finished in 2.24s (13.10s CPU time)      

Ran 1 test suite in 2.28s (2.24s CPU time): 8 tests passed, 0 failed, 0 skipped (8 total tests)

Additional Resources

• Foundry Documentation

• Polystream Documentation