Hmbown/CodeWhale · error

snippet regex pattern is valid

Error message

snippet regex pattern is valid

What it means

Panic compiling the DuckDuckGo snippet pattern — a two-alternative regex matching `<a class="result__snippet">` or `<div class="result__snippet">`, with the match taken from capture group 1 or 2. Like the other scrape getters it is a hardcoded literal behind `SNIPPET_RE.get_or_init`, so the expect fires only when an edit made the literal syntactically invalid (the alternation and nested quotes are the easy parts to break).

Source

Thrown at crates/tui/src/tools/web/scrape.rs:43

static SNIPPET_RE: OnceLock<Regex> = OnceLock::new();
static TAG_RE: OnceLock<Regex> = OnceLock::new();
static BING_RESULT_RE: OnceLock<Regex> = OnceLock::new();
static BING_TITLE_RE: OnceLock<Regex> = OnceLock::new();
static BING_SNIPPET_RE: OnceLock<Regex> = OnceLock::new();

fn get_title_re() -> &'static Regex {
    TITLE_RE.get_or_init(|| {
        Regex::new(r#"<a[^>]*class=\"result__a\"[^>]*href=\"([^\"]+)\"[^>]*>(.*?)</a>"#)
            .expect("title regex pattern is valid")
    })
}

fn get_snippet_re() -> &'static Regex {
    SNIPPET_RE.get_or_init(|| {
        Regex::new(
            r#"<a[^>]*class=\"result__snippet\"[^>]*>(.*?)</a>|<div[^>]*class=\"result__snippet\"[^>]*>(.*?)</div>"#,
        )
        .expect("snippet regex pattern is valid")
    })
}

fn get_tag_re() -> &'static Regex {
    TAG_RE.get_or_init(|| Regex::new(r"<[^>]+>").expect("tag regex pattern is valid"))
}

fn get_bing_result_re() -> &'static Regex {
    BING_RESULT_RE.get_or_init(|| {
        Regex::new(r#"(?is)<li[^>]*class=\"[^\"]*\bb_algo\b[^\"]*\"[^>]*>(.*?)</li>"#)
            .expect("bing result regex pattern is valid")
    })
}

fn get_bing_title_re() -> &'static Regex {
    BING_TITLE_RE.get_or_init(|| {
        Regex::new(r#"(?is)<h2[^>]*>.*?<a[^>]*href=\"([^\"]+)\"[^>]*>(.*?)</a>"#)
            .expect("bing title regex pattern is valid")

View on GitHub (pinned to 0c42157ee5)

Solutions

1. Fix the literal and validate it compiles in the Rust regex flavor before committing.
2. Force-initialize the getter in a unit test so CI catches syntax breaks.
3. Run the scrape test target after any pattern edit.

Example fix

// before
Regex::new(
    r#"<a[^>]*class=\"result__snippet\"[^>]*>(.*?)</a>|<div[^>]*class=\"result__snippet\"[^>]*>(.*?)</div>"#,
).expect("snippet regex pattern is valid")

// after: validate the edited pattern in isolation first
#[test]
fn snippet_pattern_edits_compile() {
    let re = get_snippet_re();
    assert_eq!(re.captures_len() - 1, 2); // two capture groups preserved
}

#[test]
fn snippet_pattern_compiles_with_two_groups() {
    let re = get_snippet_re();
    assert_eq!(re.captures_len() - 1, 2);
}

let snippets = std::panic::catch_unwind(|| collect_snippets(&html))
    .unwrap_or_default();

When it happens

Trigger: Editing the snippet literal and leaving an unbalanced parenthesis, a broken `|` alternation, or a malformed escape; the first `parse_duckduckgo_results` call after that build panics in `get_snippet_re`'s `get_or_init`.

Common situations: Loosening the snippet selector for a DDG markup change; pasting a pattern written for a regex dialect with different escape rules (e.g. escaping `/` or using `\/` unnecessarily inside a raw string).

Related errors

• title regex pattern is valid
• bing result regex pattern is valid
• bing title regex pattern is valid
• bing snippet regex pattern is valid
• tag regex pattern is valid

AI-assisted analysis of Hmbown/CodeWhale@0c42157ee5 (2026-08-20). Data as JSON: /api/errors/26af141c1e3d0c93. Report an issue: GitHub.