web3-testing
Test smart contracts with Hardhat
Writing comprehensive tests for smart contracts is complex and time-consuming. This skill provides ready-to-use patterns for unit tests, integration tests, fuzzing, gas optimization, and mainnet forking using Hardhat and Foundry.
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Using "web3-testing". Write a Hardhat unit test for an ERC20 token contract
Expected outcome:
- Deployment test: Verifies owner assignment and total supply
- Transfer test: Confirms token transfers between accounts
- Event test: Checks Transfer and Approval event emissions
- Balance test: Validates balance changes after transfers
- Time test: Tests time-locked token release functionality
Using "web3-testing". Create a Foundry test for token transfers with fuzzing
Expected outcome:
- Fuzz test: Tests transfers with random amounts within valid range
- Boundary test: Handles zero and maximum transfer amounts
- Prank test: Simulates different sender addresses
- Event test: Verifies emitted Transfer events with correct parameters
Security Audit
SafeDocumentation-only skill containing code examples and best practices for smart contract testing. Static findings are false positives triggered by blockchain testing terminology (prank, fork, deal), environment variable references demonstrating secure secret handling patterns, and markdown code block syntax. The skill teaches recommended security practices and has no executable code, network calls, or file access capabilities.
Risk Factors
🔑 Env variables (1)
Quality Score
What You Can Build
Set up test suites
Create comprehensive test suites for Solidity contracts using Hardhat and Foundry patterns.
Validate DeFi integrations
Test smart contracts against mainnet forks of existing DeFi protocols like Uniswap.
Fuzz contract logic
Use Foundry fuzzing to discover edge cases and potential vulnerabilities in smart contracts.
Try These Prompts
Write a Hardhat unit test for an ERC20 token contract that tests deployment, transfers, and approval events.
Create an integration test for a staking contract that tests deposit, claim rewards, and withdrawal flows using Hardhat.
Write a test that forks Ethereum mainnet and tests Uniswap V2 swap functionality with a fork of the DAI token.
Create a gas comparison test between two different implementations of the same smart contract function using Hardhat gas reporter.
Best Practices
- Use fixtures to avoid code duplication across multiple test cases
- Aim for at least 90% test coverage on critical contract functions
- Test edge cases like zero addresses, maximum values, and reentrancy scenarios
Avoid
- Avoid testing multiple unrelated scenarios in a single test function
- Do not use mainnet forking in all tests - reserve for integration scenarios
- Avoid hardcoding private keys or secrets in test files