Learn-skills.dev solidity-testing

[AUTO-INVOKE] MUST be invoked BEFORE writing or modifying any test files (*.t.sol). Covers test structure, naming conventions, coverage requirements, fuzz testing, and Foundry cheatcodes. Trigger: any task involving creating, editing, or running Solidity tests.

install

source · Clone the upstream repo

git clone https://github.com/NeverSight/learn-skills.dev

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/NeverSight/learn-skills.dev "$T" && mkdir -p ~/.claude/skills && cp -r "$T/data/skills-md/0xlayerghost/solidity-agent-kit/solidity-testing" ~/.claude/skills/neversight-learn-skills-dev-solidity-testing && rm -rf "$T"

manifest: data/skills-md/0xlayerghost/solidity-agent-kit/solidity-testing/SKILL.md

source content

Testing Standards

Language Rule

Always respond in the same language the user is using. If the user asks in Chinese, respond in Chinese. If in English, respond in English.

Test Organization

One test contract per source contract:
```
MyToken.sol
```
→
```
MyToken.t.sol
```
File location: All tests in
```
test/
```
directory

Naming:

test_<feature>_<scenario>

for passing tests,

testFail_<feature>_<scenario>

for expected reverts

Example:

test_transfer_revertsWhenInsufficientBalance

Example:
```
test_stake_updatesBalanceCorrectly
```

Independence: Each test must run in isolation — use
```
setUp()
```
for shared state, no cross-test dependencies
Filtering: Support
```
--match-test
```
and
```
--match-contract
```
for targeted runs

Coverage Requirements

Every core function must have tests covering:

Scenario	What to verify
Happy path	Standard input → expected output, correct state changes
Permission checks	Unauthorized caller → `vm.expectRevert` with correct error
Boundary conditions	Zero values, max values ( `type(uint256).max` ), off-by-one
Failure scenarios	Every `require` / `revert` / custom error path
State changes	Storage updates, balance changes, event emissions ( `vm.expectEmit` )
Edge cases	Empty arrays, duplicate calls, self-transfers

Foundry Cheatcodes Quick Reference

Cheatcode	Usage
`vm.prank(addr)`	Next call from `addr`
`vm.startPrank(addr)`	All calls from `addr` until `vm.stopPrank()`
`vm.warp(timestamp)`	Set `block.timestamp`
`vm.roll(blockNum)`	Set `block.number`
`vm.deal(addr, amount)`	Set ETH balance
`vm.expectRevert(error)`	Next call must revert with specific error
`vm.expectEmit(true,true,false,true)`	Verify event emission (topic checks)
`vm.record()` / `vm.accesses()`	Track storage reads/writes
`makeAddr("name")`	Create labeled address for readable traces

Fuzz Testing Rules

All math-heavy and fund-flow functions must have fuzz tests

Pattern:

function testFuzz_<name>(uint256 amount) public

Use

vm.assume()

to constrain inputs:

vm.assume(amount > 0 && amount < MAX_SUPPLY);

Default runs: 256 — increase to 10,000+ for critical functions:
```
forge test --fuzz-runs 10000
```

Common Commands

# Run all tests
forge test

# Run specific test function
forge test --match-test test_transfer

# Run specific test contract
forge test --match-contract MyTokenTest

# Verbose output with full trace
forge test -vvvv

# Gas report
forge test --gas-report

# Fuzz with more runs
forge test --fuzz-runs 10000

# Test coverage
forge coverage

# Coverage with report
forge coverage --report lcov