plandex-ai/plandex · error

failed to parse file: %v

Error message

failed to parse file: %v

What it means

After resolving a parser, multi.go parses each file's bytes with parser.ParseCtx(ctx, nil, contentBytes). If the tree-sitter parse itself fails (e.g. context cancellation, operation/timeout limit), the goroutine wraps it as 'failed to parse file: %v'.

Source

Thrown at app/server/syntax/file_map/multi.go:105

			var parser *tree_sitter.Parser
			file := filepath.Base(path)
			if strings.Contains(strings.ToLower(file), "dockerfile") {
				parser = syntax.GetParserForLanguage(shared.LanguageDockerfile)
			} else {
				parser, _, _, _ = syntax.GetParserForPath(path)

				if parser == nil {
					errCh <- fmt.Errorf("unsupported file type: %s", path)
					return
				}
			}

			contentBytes := []byte(content)

			// Parse file
			tree, err := parser.ParseCtx(ctx, nil, contentBytes)
			if err != nil {
				errCh <- fmt.Errorf("failed to parse file: %v", err)
				return
			}
			defer tree.Close()

			mu.Lock()
			defer mu.Unlock()
			trees[path] = string(tree.RootNode().String())
			errCh <- nil
		}(path, content)
	}

	for i := 0; i < len(inputs); i++ {
		err := <-errCh
		if err != nil {
			return nil, err
		}
	}

View on GitHub (pinned to e2d772072e)

Solutions

1. Inspect the wrapped '%v' cause; if it is a timeout/operation-limit, increase limits or parse in chunks
2. Increase the context deadline or remove cancellation for long batches
3. Exclude very large/generated files from mapping
4. Lower concurrency (semaphore size) to reduce resource pressure

Example fix

// before
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
// after
ctx, cancel := context.WithTimeout(context.Background(), 60*time.Second)
MultiMapFile(ctx, paths)

if len(content) > maxParseSize {
    return fmt.Errorf("file %s too large to map (%d bytes)", path, len(content))
}
if ctx.Err() != nil {
    return ctx.Err()
}

err := <-errCh
if err != nil && strings.Contains(err.Error(), "failed to parse file") {
    if strings.Contains(err.Error(), "operation limit") || strings.Contains(err.Error(), "timeout") {
        // retry with larger limits or skip large file
    }
}

When it happens

Trigger: ParseCtx returns a non-nil error while concurrently mapping a file — most commonly ctx cancellation/timeout or hitting the operation limit on very large files.

Common situations: Mapping huge generated files under a context deadline; parent context cancelled mid-batch; resource limits reached during concurrent parsing of many large files.

Understand the failure class

• Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

Related errors

• error mapping file %s: %v
• failed to delete contexts: %v
• failed to read the file %s: %v
• error getting plan current branch: %v
• panic in UpdateContexts: %v\n%s

AI-assisted analysis of plandex-ai/plandex@e2d772072e (2026-09-05). Data as JSON: /api/errors/e656153d6b70767b. Report an issue: GitHub.