escape-case.md

Require escape sequences to use uppercase values

Enforces defining escape sequence values with uppercase characters rather than lowercase ones. This promotes readability by making the escaped value more distinguishable from the identifier.

This rule is fixable.

Fail

const foo = '\xa9';
const foo = '\ud834';
const foo = '\u{1d306}';
const foo = '\ca';

Pass

const foo = '\xA9';
const foo = '\uD834';
const foo = '\u{1D306}';
const foo = '\cA';