oxc-project/oxc · warning · OxcDiagnostic

{un_prefixed_name} should match {raw_pattern}

Error message

{un_prefixed_name} should match {raw_pattern}

What it means

Diagnostic from the shared jest/vitest `valid-title` rule (must_match path). It fires when a title (with the test/describe prefix stripped, hence `un_prefixed_name`) does not match the regex configured in the rule's `mustMatch` option. It enforces a project-wide title convention, e.g. unit titles must start with a verb in third person.

Source

Thrown at crates/oxc_linter/src/rules/shared/jest_vitest/valid_title.rs:54

    OxcDiagnostic::warn("Should not have duplicate prefix")
        .with_help("The function name already has the prefix, try to remove the duplicate prefix")
        .with_label(span)
}

fn accidental_space_diagnostic(span: Span) -> OxcDiagnostic {
    OxcDiagnostic::warn("Should not have leading or trailing spaces")
        .with_help("Remove the leading or trailing spaces")
        .with_label(span)
}

fn disallowed_word_diagnostic(word: &str, span: Span) -> OxcDiagnostic {
    OxcDiagnostic::warn(format!("{word} is not allowed in test title"))
        .with_help("It is included in the `disallowedWords` of your config file, try to remove it from your title")
        .with_label(span)
}

pub fn must_match_diagnostic(message: &str, span: Span) -> OxcDiagnostic {
    OxcDiagnostic::warn(message.to_string())
        .with_help("Make sure the title matches the `mustMatch` of your config file")
        .with_label(span)
}

pub fn must_not_match_diagnostic(message: &str, span: Span) -> OxcDiagnostic {
    OxcDiagnostic::warn(message.to_string())
        .with_help("Make sure the title does not match the `mustNotMatch` of your config file")
        .with_label(span)
}

pub const DOCUMENTATION: &str = r"
### What it does

Checks that the titles of Jest and Vitest blocks are valid.

Titles must be:
- not empty,
- strings,

View on GitHub (pinned to e1e7af627c)

Solutions

1. Rewrite the title to satisfy the configured pattern.
2. Loosen or fix the regex if it rejects legitimate titles (test it against real titles before enforcing in CI).
3. Apply the convention incrementally: enable mustMatch as warning first, fix hotspots, then promote to error.

Example fix

// before
// config: "valid-title": ["error", { "mustMatch": "^[a-z]+( [a-zA-Z0-9]+)+$" }]
it('ADD numbers', () => { /* ... */ });

// after
it('adds two numbers', () => { /* ... */ });

const mustMatch = /^[a-z]+( [a-zA-Z0-9]+)+$/; // mirror oxlint mustMatch
for (const [fn, title] of collectTestCalls(src)) {
  if (!mustMatch.test(title)) console.warn(`title '${title}' fails mustMatch`);
}

When it happens

Trigger: Configure `mustMatch` as a pattern string or `[pattern, flags]` array, e.g. `{ "mustMatch": "^[a-z]+( [a-zA-Z0-9]+)+$" }` or `"^[A-Z]" `; a title like `it('does stuff', fn)` that fails the regex yields '{title} should match {rawPattern}' with help pointing at the `mustMatch` config.

Common situations: Org style guides (e.g. 'should...' or given/when/then titles) enforced mechanically; enabling mustMatch on a legacy suite and getting hundreds of hits; overly strict regexes that reject spaces or punctuation used in existing titles.

Related errors

• {un_prefixed_name} should not match {raw_pattern}
• {word} is not allowed in test title
• Should not have duplicate prefix
• Title must be a string
• Should not have an empty title

AI-assisted analysis of oxc-project/oxc@e1e7af627c (2026-08-20). Data as JSON: /api/errors/44429646dc8cf506. Report an issue: GitHub.