Function names should use mixedCase

Severity: Info ID: mixed-case-function

Flags function names that do not follow mixedCase.

What it does

Reports functions whose names contain embedded underscores, start with an uppercase letter, or otherwise deviate from mixedCase. Leading and trailing underscores are preserved, and single-character names are not checked. Test functions starting with test, invariant_, or statefulFuzz, configured uppercase patterns (for example, ERC20), and external constant-style getters are exempted.

Why is this bad?

The Solidity style guide recommends mixedCase for function names. Consistent style makes call sites uniform, helps editor tooling, and reduces friction in code review.

Example

Bad

solidity

function get_balance() external view returns (uint256);
function GetBalance()  external view returns (uint256);

Good

solidity

function getBalance() external view returns (uint256);

Configuration

Set mixed_case_exceptions under [lint.lint_specific] in foundry.toml to replace the default list of allowed uppercase patterns (ERC, URI, ID, URL, API, JSON, XML, HTML, HTTP, and HTTPS):

toml

[lint.lint_specific]
mixed_case_exceptions = ["ERC", "URI", "NFT"]