no-empty-array-literal

Disallow bare [] in places where the rule wants new Array() or new Array<T>() instead.

Rule details Problem

This rule reports empty array literals with no elements.

It does not ban every []. By default, several contexts are allowed, including call arguments, return statements, object property values, JSX attributes, conditional branches, logical fallbacks, for...of right-hand sides, typed assignment defaults, type assertions, and typed variable declarations that already spell out an array type.

When the rule can read an explicit element type, it auto-fixes to new Array<T>() by default. When it cannot, it still reports the literal and offers new Array() as a suggestion.

One option is kept for compatibility

ignoreInferredNonEmptyLiterals is accepted by the rule, but it does not change behavior. Non-empty array literals stay allowed either way.

Options

Main options

• inferTypeForEmptyArrayFix, default false, lets the rule ask TypeScript for a contextual element type before fixing
• requireExplicitGenericOnNewArray, default true, keeps new Array<T>() when the element type is known
• allowedEmptyArrayContexts, all keys default to true, controls which safe contexts can still use []
• ignoreInferredNonEmptyLiterals, default true, accepted but has no effect

eslint.config.ts

import plugin from "@pobammer-ts/eslint-cease-nonsense-rules";

export default [
  {
    plugins: { "cease-nonsense": plugin },
    rules: {
      "cease-nonsense/no-empty-array-literal": [
        "error",
        {
          allowedEmptyArrayContexts: {
            callArguments: false,
            returnStatements: false,
          },
          inferTypeForEmptyArrayFix: true,
          requireExplicitGenericOnNewArray: true,
        },
      ],
    },
  },
];

Allowed contexts

allowedEmptyArrayContexts supports these keys:

• arrowFunctionBody
• assignmentExpressions
• assignmentPatterns
• callArguments
• conditionalExpressions
• forOfStatements
• jsxAttributes
• logicalExpressions
• propertyValues
• returnStatements
• typeAssertions

Examples

Incorrect

const values = [];

class Store {
  items: Array<string> = [];
  queue = [];
}

Correct

const values: Array<string> = [];

function readAll(input: Array<number> = []) {
  return input;
}

const fallback = data || [];
const seeded = [1, 2, 3];

Related rules

array-type-genericEnforce `Array` and `ReadonlyArray` type syntax.

no-array-constructor-elementsCheck how `new Array(...)` is used once you adopt constructor form.