oxc/bad-bitwise-operator

& and | are one keystroke away from && and ||, and the code still runs. They convert both sides to 32-bit integers, so "Ann" | "guest" is 0, not a name. They also evaluate both sides every time, so user & user.city throws when user is undefined.

The rule reports three shapes:

• user & user.city: a variable, with a property of that variable on the right.
• title | "Untitled": a variable, with something that clearly isn't a number on the right.
• title |= "Untitled": the same for |=.

A number, a variable, null and arithmetic can be numbers, so they're allowed on the right. A string, an object, an array, typeof x, !x, a call and a property access are reported.

--fix-suggestions replaces the operator with the logical one.

Configure#

Off by default. To turn it on:

[lint.rules]
"oxc/bad-bitwise-operator" = "error" # or "warn"

Examples#

const city = user & user.city;
const label = title | "Untitled";
options |= {};

const city = user && user.city;
const label = title || "Untitled";
options ||= {};

const mode = flags | 4;
const both = read | write;

When not to use it#

Code that combines flags is reported when the right side is a property or a call, even though | is what you mean. Leave the rule off in that code.

const mode = flags | Mode.Write;