helix-editor/helix · warning

Failed to compile regex

Error message

Failed to compile regex

What it means

The workspace symbol picker builds a matcher from the typed pattern via state.regex_matcher_builder (the regex crate). Patterns that are not valid regex — unbalanced groups, dangling quantifiers, unsupported look-around — abort the search with 'Failed to compile regex'; the underlying compile error is logged at info level, and a later successful compile clears the stale statusline error.

Source

Thrown at helix-term/src/commands/syntax.rs:344

                }
            }
        }
        if !state.search_root.exists() {
            return async { Err(anyhow::anyhow!("Current working directory does not exist")) }
                .boxed();
        }
        let matcher = match state.regex_matcher_builder.build(query) {
            Ok(matcher) => {
                // Clear any "Failed to compile regex" errors out of the statusline.
                editor.clear_status();
                matcher
            }
            Err(err) => {
                log::info!(
                    "Failed to compile search pattern in workspace symbol search: {}",
                    err
                );
                return async { Err(anyhow::anyhow!("Failed to compile regex")) }.boxed();
            }
        };
        let pattern = Arc::new(pattern);
        let injector = injector.clone();
        let loader = editor.syn_loader.load();

        let documents: HashSet<_> = editor
            .documents()
            .filter_map(Document::path)
            .map(ToOwned::to_owned)
            .collect();

        async move {
            let searcher = state.searcher_builder.build();
            state.walk_builder.build_parallel().run(|| {
                let mut searcher = searcher.clone();
                let matcher = matcher.clone();
                let injector = injector.clone();

View on GitHub (pinned to 079a789e8c)

Solutions

1. Escape metacharacters: 'Vec\<T\>', 'operator\(\)'.
2. Remove unsupported constructs (look-around, backreferences) — regex cannot compile them.
3. Type a simpler metacharacter-free prefix first, then refine.

Example fix

# before
Vec<T>
# after
Vec\<T\>

if regex::Regex::new(pattern).is_ok() {
    // safe to submit to the workspace symbol prompt
}

fn is_valid_symbol_regex(p: &str) -> bool {
    regex::Regex::new(p).is_ok()
}

When it happens

Trigger: Typing '(', '(?<=x)', '*sym', or '[a-' into the workspace symbol prompt while it dynamically re-filters.

Common situations: Symbol names containing regex metacharacters (generics like 'Vec<T>', 'operator()'); PCRE-style look-around habits; mid-typing states.

Related errors

• Failed to compile regex
• Current working directory does not exist

AI-assisted analysis of helix-editor/helix@079a789e8c (2026-08-16). Data as JSON: /api/errors/f665737f5d3a3907. Report an issue: GitHub.