fix(linter): Improve docs, diagnostic message, and implementation of typescript/consistent-indexed-object-style rule.

[connorshea]

Diagnostic messages are grammatically correct and also tell the user what to actually do now. And the implementation of the rule has been refactored a bit to ensure the enum is used for the config options rather than a boolean, which was confusing (especially in the generated docs).

Docs now look like this:

What it does

Choose between requiring either Record type or indexed signature types.

These two types are equivalent, this rule enforces consistency in picking one style over the other:

type Foo = Record<string, unknown>;

type Foo = {
  [key: string]: unknown;
}

Why is this bad?

Inconsistent style for indexed object types can harm readability in a project.

Examples

Examples of incorrect code for this rule with
consistent-indexed-object-style: ["error", "record"] (default):

interface Foo {
  [key: string]: unknown;
}
type Foo = {
  [key: string]: unknown;
};

Examples of correct code for this rule with
consistent-indexed-object-style: ["error", "record"] (default):

type Foo = Record<string, unknown>;

Examples of incorrect code for this rule with
consistent-indexed-object-style: ["error", "index-signature"]:

type Foo = Record<string, unknown>;

Examples of correct code for this rule with
consistent-indexed-object-style: ["error", "index-signature"]:

interface Foo {
  [key: string]: unknown;
}
type Foo = {
  [key: string]: unknown;
};

Configuration

This rule accepts a configuration object with the following properties:

preferredStyle

type: "record" | "index-signature"

default: "record"

When set to record, enforces the use of a Record for indexed object types, e.g. Record<string, unknown>.
When set to index-signature, enforces the use of indexed signature types, e.g. { [key: string]: unknown }.

[graphite-app]

How to use the Graphite Merge Queue

Add either label to this PR to merge it via the merge queue:

• 0-merge - adds this PR to the back of the merge queue
• hotfix - for urgent hot fixes, skip the queue and merge this PR next

You must have a Graphite account in order to use the merge queue. Sign up using this link.

An organization admin has enabled the Graphite Merge Queue in this repository.

Please do not merge from GitHub as this will restart CI on PRs being processed by the merge queue.

[Copilot]

Pull Request Overview

This PR improves the diagnostic messages and documentation for the typescript/consistent-indexed-object-style linter rule to make them more grammatically correct and actionable.

Key Changes:

• Fixed grammar in diagnostic messages ("A index signature" → "An index signature")
• Enhanced help messages to provide concrete examples of what to use
• Improved documentation examples with better formatting and clearer configuration examples

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
crates/oxc_linter/src/rules/typescript/consistent_indexed_object_style.rs	Updated diagnostic function to provide better messages with examples, improved documentation comments, and removed redundant parameters
crates/oxc_linter/src/snapshots/typescript_consistent_indexed_object_style.snap	Updated test snapshots to reflect new diagnostic and help messages

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[codspeed-hq]

CodSpeed Performance Report

Merging #15750 will not alter performance

_{Comparing consist-docs (5234b12) with main (3ab750a)}

Summary

✅ 4 untouched
⏩ 33 skipped¹

Footnotes

1. 33 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[camc314]

Merge activity

• Nov 16, 10:27 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Nov 16, 10:29 PM UTC: camc314 added this pull request to the Graphite merge queue.
• Nov 16, 10:34 PM UTC: Merged by the Graphite merge queue.