common:
- rename `Folder` to `Fold`
- folder.then()
- impl Fold for Box<F>
- impl Fold<T> for &mut F where F: Fold<T>
transforms:
- make Simplifier private
- organize compat
codegen:
- use `Mark` to avoid deoptimization
swc:
- upgrade rayon and use global thread pool instead
- Parser and lexer for lastest ecma spec https://tc39.github.io/ecma262
- Lexer is currently very inefficient
- Use https://github.com/tc39/test262-parser-tests/ for testing.
- Implement proc-macro based ast folder and assert_eq_ignore_span! based on it.
- Some utilities for proc macro at /macros/common
