tinyhumansai/openhuman · error

keyword rule regex is well-formed

Error message

keyword rule regex is well-formed

What it means

Static-invariant panic in keyword_rule(): the rule table builds case-insensitive, word-boundaried alternations from hardcoded term lists, so Regex::new can only fail on a developer mistake (unescaped regex metacharacter in a term, or an empty list producing an invalid pattern). It fires at PII-rule-table initialization, before any user data is scanned.

Source

Thrown at src/openhuman/security/pii/rules.rs:37

/// A single detection rule: matches [`regex`](Rule::regex), attributes hits to
/// [`category`](Rule::category), and — if present — only counts a match when
/// [`validator`](Rule::validator) confirms it.
pub(crate) struct Rule {
    pub category: PiiCategory,
    pub regex: Regex,
    /// Optional structural check applied to each raw match before it counts.
    pub validator: Option<fn(&str) -> bool>,
}

/// Build a keyword rule: a case-insensitive, word-boundaried alternation over
/// `terms`, all attributed to `category`.
fn keyword_rule(category: PiiCategory, terms: &[&str]) -> Rule {
    let alternation = terms.join("|");
    let pattern = format!(r"(?i)\b(?:{alternation})\b");
    Rule {
        category,
        regex: Regex::new(&pattern).expect("keyword rule regex is well-formed"),
        validator: None,
    }
}

/// Build a pattern rule from a raw regex string.
fn pattern_rule(category: PiiCategory, pattern: &str, validator: Option<fn(&str) -> bool>) -> Rule {
    Rule {
        category,
        regex: Regex::new(pattern).expect("pattern rule regex is well-formed"),
        validator,
    }
}

/// Luhn checksum validation for candidate payment-card numbers. Strips
/// separators first; requires 13–19 digits.
pub(crate) fn is_luhn_valid(raw: &str) -> bool {
    let digits: Vec<u8> = raw
        .bytes()

View on GitHub (pinned to 7491200858)

Solutions

1. Escape each term with regex::escape before joining with '|'
2. Add a unit test per rule asserting compilation so a bad term fails CI, not boot
3. Guard against empty term lists producing '(?i)\b(?:)\b'

When it happens

Trigger: Thrown at src/openhuman/security/pii/rules.rs:37 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of tinyhumansai/openhuman@7491200858 (2026-08-17). Data as JSON: /api/errors/12e0628c5774a697. Report an issue: GitHub.