Disallow Number Literals That Lose Precision (no-loss-of-precision)
"extends": "eslint:recommended" property in a configuration file enables this rule.
This rule would disallow the use of number literals that immediately lose precision at runtime when converted to a JS
Number due to 64-bit floating-point rounding.
Numbers are stored as double-precision floating-point numbers according to the IEEE 754 standard. Because of this, numbers can only retain accuracy up to a certain amount of digits. If the programmer enters additional digits, those digits will be lost in the conversion to the
Number type and will result in unexpected behavior.
Examples of incorrect code for this rule:
/*eslint no-loss-of-precision: "error"*/ const x = 9007199254740993 const x = 5123000000000000000000000000001 const x = 1230000000000000000000000.0 const x = .1230000000000000000000000 const x = 0X20000000000001 const x = 0X2_000000000_0001;
Examples of correct code for this rule:
/*eslint no-loss-of-precision: "error"*/ const x = 12345 const x = 123.456 const x = 123e34 const x = 12300000000000000000000000 const x = 0x1FFFFFFFFFFFFF const x = 9007199254740991 const x = 9007_1992547409_91
This rule was introduced in ESLint 7.1.0.