transpiler / swc things to double-check #1613

Capturing a few items from my personal to-do list that need to be double-checked:

• when swc: true, make sure path is an absolute path to ts-node's own SWC transpiler

  • absolute path to the swc transpiler, which itself is responsible for finding and loading @swc/core or @swc/wasm

• Within swc transpiler

  • use tsconfig-relative require() to find swc first
  • fallback to require() relative to ts-node, in case ts-node is a global installation

• When transpiler is a string, do project-local require

• When transpiler is the ts-node/transpilers/swc-experimental, also fallback to absolute path to globally-installed-ts-node-transpiler for backwards compat

  • can we do this with require.resolve(specifier, {paths})?

• Consider genericizing this require() logic

  • We have several use-cases for this: locate transpiler, locate compiler, locate @swc/core|wasm, locate --require
  • make a single require.resolve wrapper that understands the nuance of how we locate dependencies in all the above situations
    - if specifier comes from a tsconfig, attempt to resolve relative to tsconfig
    - if specifier comes from API or CLI, attempt to resolve relative to ...
    - CWD?
    - entrypoint? (for shebangs?) No, the shebang case is handled by having a tsconfig next to the entrypoint

• tweak swc jsdoc to link to ts-node website, since it requires installing additional deps