docs(linter): Add config option docs for unicorn/filename-case rule.

[connorshea]

Part of #14743.

• Refactors the FilenameCase rule code
• Adds some additional tests for the rule.
• Matches the original rule by ignoring index.js, index.ts, etc automatically, to avoid problems with the rule causing invalid filenames in various frameworks.
• Adds schema-specific structs to match the actual config object an end-user will set up. I didn't want to refactor the entire rule to match the end-user config object for now, as that seemed like it'd be really difficult to get working.

To review the changeset it'd be best to go through it commit-by-commit.

Generated docs:

## Configuration

This rule accepts a configuration object with the following properties:

### case

type: `"kebabCase" | "camelCase" | "snakeCase" | "pascalCase"`

default: `"kebabCase"`

The case style to enforce for filenames.

You can set the `case` option like this:
\```json
"unicorn/filename-case": [
"error",
{
"case": "kebabCase"
}
]
\```


### cases

type: `object`

default: `{"kebabCase":true, "camelCase":false, "snakeCase":false, "pascalCase":false}`

The case style(s) to allow/enforce for filenames. `true` means the case style is allowed, `false` means it is banned.

You can set the `cases` option like this:
\```json
"unicorn/filename-case": [
"error",
{
"cases": {
"camelCase": true,
"pascalCase": true
}
}
]
\```

#### cases.camelCase

type: `boolean`

default: `false`

Whether camel case is allowed, e.g. `someFileName.js`.


#### cases.kebabCase

type: `boolean`

default: `true`

Whether kebab case is allowed, e.g. `some-file-name.js`.


#### cases.pascalCase

type: `boolean`

default: `false`

Whether pascal case is allowed, e.g. `SomeFileName.js`.


#### cases.snakeCase

type: `boolean`

default: `false`

Whether snake case is allowed, e.g. `some_file_name.js`.


### ignore

type: `[
  string,
  null
]`


A regular expression pattern for filenames to ignore.

You can set the `ignore` option like this:
\```json
"unicorn/filename-case": [
"error",
{
"ignore": "^foo.*$"
}
]
\```

### multipleFileExtensions

type: `boolean`

default: `true`

Whether to treat additional, `.`-separated parts of a filename as
parts of the extension rather than parts of the filename.

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[Copilot]

Pull request overview

This pull request adds configuration documentation for the unicorn/filename-case linter rule by introducing schema-specific structs that match the end-user configuration format. The PR refactors the rule implementation to separate the internal configuration structure from the documentation schema, adds additional test cases including automatic exemption of index.* files, and improves error messages to use standardized case naming (e.g., "kebab-case" instead of "kebab case").

Key changes:

• Adds FilenameCaseConfigJson, FilenameCaseConfigJsonCases, and FilenameCaseJsonOptions structs for schema documentation
• Updates error messages to use standardized case names (kebab-case, camelCase, snake_case, PascalCase)
• Automatically ignores index.* files to prevent framework-specific filename issues
• Removes the rule from the configuration documentation exceptions list

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
crates/oxc_linter/src/rules/unicorn/filename_case.rs	Adds schema documentation structs, refactors configuration handling, updates error messages to use standardized case names, and adds automatic index.* file exemption
crates/oxc_linter/src/snapshots/unicorn_filename_case.snap	Updates test snapshots to reflect new standardized case name format in error messages
crates/oxc_linter/tests/rule_configuration_documentation_test.rs	Removes unicorn/filename-case from the exceptions list as it now has proper schema documentation

Comments suppressed due to low confidence (1)

crates/oxc_linter/src/rules/unicorn/filename_case.rs:163

• [nitpick] The documentation header uses kebabCase but the actual case style name should be kebab-case (with a hyphen) to match the standardized naming used in error messages (lines 265, 267) and be consistent with how the case is commonly written. This affects lines 163, 169, 175, and 181.

    /// #### `kebabCase`

---

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[codspeed-hq]

CodSpeed Performance Report

Merging #16280 will not alter performance

_{Comparing filename-case-updates (76a5dc8) with main (40b0134)¹}

Summary

✅ 4 untouched
⏩ 41 skipped²

Footnotes

1. No successful run was found on main (e24aabd) during the generation of this report, so 40b0134 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

2. 41 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

• Dec 7, 2:40 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Dec 7, 2:40 PM UTC: camc314 added this pull request to the Graphite merge queue.
• Dec 7, 2:45 PM UTC: Merged by the Graphite merge queue.