Numeric literal with too many digits

Severity: Info ID: too-many-digits

Flags numeric literals containing five or more consecutive zeros, which are easy to misread.

What it does

Reports Solidity and Yul numeric literals that contain a run of 5 or more 0 characters. Decimal literals with scientific notation, literals with a sub-denomination, and 40-digit hexadecimal address literals are skipped. Other hexadecimal literals remain in scope because long padded masks and bit patterns are also difficult to review.

Why is this bad?

Long sequences of zeros are difficult to count visually, and an off-by-one zero is a common bug (e.g. funding 1_000_000 instead of 10_000_000). Use scientific notation, sub-denominations, or underscore separators to make the magnitude obvious.

Example

Bad

uint256 amount = 1000000000000000000;

Good

uint256 amount = 1e18;
uint256 amount2 = 1 ether;
uint256 amount3 = 1_000_000_000_000_000_000;