This document gives a high level overview of swc internals. You may find it useful if you want to contribute to swc or if you are interested in the inner workings of swc.
swc uses proc macro extensively to reduce work. Please see links below to know what each macro do.
And some adhoc-macros are used.
These macro breaks macro hygiene.
swc uses official ecmascript conformance test suite called test262 for testing.
Parser tests ensures that parsed result of test262/pass is identical with test262/pass-explicit.
Codegen tests ensures that generated code is equivalent to goldened reference files located at tests/references.