eslint/id-length Style
What it does
This rule enforces a minimum and/or maximum identifier length convention by counting the graphemes for a given identifier.
Why is this bad?
Very short identifier names like e, x, _t or very long ones like hashGeneratorResultOutputContainerObject can make code harder to read and potentially less maintainable. To prevent this, one may enforce a minimum and/or maximum identifier length.
Examples
Examples of incorrect code for this rule:
/* id-length: "error" */ // default is minimum 2-chars ({ "min": 2 })
const x = 5;
obj.e = document.body;
const foo = function (e) {};
try {
dangerousStuff();
} catch (e) {
// ignore as many do
}
const myObj = { a: 1 };
(a) => {
a * a;
};
class y {}
class Foo {
x() {}
}
class Bar {
#x() {}
}
class Baz {
x = 1;
}
class Qux {
#x = 1;
}
function bar(...x) {}
function baz([x]) {}
const [z] = arr;
const {
prop: [i],
} = {};
function qux({ x }) {}
const { j } = {};
const { prop: a } = {};
({ prop: obj.x } = {});Examples of correct code for this rule:
/* id-length: "error" */ // default is minimum 2-chars ({ "min": 2 })
const num = 5;
function _f() {
return 42;
}
function _func() {
return 42;
}
obj.el = document.body;
const foo = function (evt) {
/* do stuff */
};
try {
dangerousStuff();
} catch (error) {
// ignore as many do
}
const myObj = { apple: 1 };
(num) => {
num * num;
};
function bar(num = 0) {}
class MyClass {}
class Foo {
method() {}
}
class Bar {
#method() {}
}
class Baz {
field = 1;
}
class Qux {
#field = 1;
}
function baz(...args) {}
function qux([longName]) {}
const { prop } = {};
const {
prop: [name],
} = {};
const [longName] = arr;
function foobar({ prop }) {}
function foobaz({ a: prop }) {}
const { a: property } = {};
({ prop: obj.longName } = {});
const data = { x: 1 }; // excused because of quotes
data["y"] = 3; // excused because of calculated property accessConfiguration
This rule accepts a configuration object with the following properties:
checkGeneric
type: boolean
default: true
Whether to check TypeScript generic type parameter names. Defaults to true.
exceptionPatterns
type: string[]
An array of regex patterns for identifiers to exclude from the rule. For example, ["^x.*"] would exclude all identifiers starting with "x".
exceptions
type: string[]
default: []
An array of identifier names that are excluded from the rule. For example, ["x", "y", "z"] would allow single-letter identifiers "x", "y", and "z".
max
type: integer
default: Infinity
The maximum number of graphemes allowed in an identifier. Defaults to no maximum (effectively unlimited).
min
type: integer
default: 2
The minimum number of graphemes required in an identifier.
properties
type: "always" | "never"
default: "always"
Whether to check property names for length.
How to use
To enable this rule using the config file or in the CLI, you can use:
{
"rules": {
"id-length": "error"
}
}import { defineConfig } from "oxlint";
export default defineConfig({
rules: {
"id-length": "error",
},
});oxlint --deny id-lengthVersion
This rule was added in v1.4.0.