moai-tool-ast-grep

AST-based code search finds complex patterns across 40+ languages by matching abstract syntax tree structures instead of plain text. This enables precise structural queries for locating specific APIs, function calls, or syntax constructs in multilingual codebases.

Codemods automate code transformations to migrate APIs and modernize codebases. By defining structural rules, you can apply bulk automated refactoring across large projects, replacing outdated function calls or modifying syntax patterns safely without manual text edits.

Security scanning templates in ast-grep detect security risks by locating vulnerable code patterns. You can run rule-driven checks using configuration files to automatically identify dangerous syntax structures and enforce security rules across your codebase.

You need to install the ast-grep CLI via Homebrew, npm, or cargo. After installation, verify the setup and execute pattern searches by specifying the target language, pattern syntax, and source directory in your terminal command.

You configure custom rules by creating an sgconfig.yml file that defines structural patterns and transformation logic. Running a scan with this configuration applies rule-driven checks to enforce coding standards and execute automated refactoring.

AST search matches abstract syntax tree structures for precise structural results, unlike regular text search which relies on string matching. This ensures accurate pattern identification across different formatting styles, making it reliable for large-scale refactoring.