ERR_UNSUPPORTED_NODE_MODULES_TYPE_STRIPPING when executing globally installed local-action on Node 23

[Radiergummi]

I'm a bit at a loss. So apparently, @github/local-action doesn't include any transpiled bundle and relies on type-stripping to run(?). But that doesn't work in Node.js right now, since it refuses to do type-stripping in a node_modules/ folder, which will be where any third-party package ends up living.
This affects both installations via npm i -g and invocations via npx.

Therefore, when installing the package as advertised in the documentation and running it on a fairly recent MacOS with node v23.10, the following occurs:

$ local-action --help
node:internal/modules/typescript:170
    throw new ERR_UNSUPPORTED_NODE_MODULES_TYPE_STRIPPING(filename);
    ^

Error [ERR_UNSUPPORTED_NODE_MODULES_TYPE_STRIPPING]: Stripping types is currently unsupported for files under node_modules, for "/opt/homebrew/lib/node_modules/@github/local-action/src/bootstrap.ts"
    at stripTypeScriptModuleTypes (node:internal/modules/typescript:170:11)
    at Module._compile (node:internal/modules/cjs/loader:1686:15)
    at Object.loadTS [as .ts] (node:internal/modules/cjs/loader:1826:10)
    at Module.load (node:internal/modules/cjs/loader:1469:32)
    at Function._load (node:internal/modules/cjs/loader:1286:12)
    at TracingChannel.traceSync (node:diagnostics_channel:322:14)
    at wrapModuleLoad (node:internal/modules/cjs/loader:235:24)
    at Module.require (node:internal/modules/cjs/loader:1491:12)
    at node:internal/modules/cjs/loader:2049:12
    at loadPreloadModules (node:internal/process/pre_execution:663:5) {
  code: 'ERR_UNSUPPORTED_NODE_MODULES_TYPE_STRIPPING'
}

Node.js v23.10.0

Am I missing something, or is this a bug? Given there are no JavaScript sources for the bootstrap script, how is this supposed to work with Node versions without type stripping support?

[ncalteen]

So apparently, @github/local-action doesn't include any transpiled bundle and relies on type-stripping to run(?).

That's correct!

But that doesn't work in Node.js right now, since it refuses to do type-stripping in a node_modules/ folder, which will be where any third-party package ends up living. This affects both installations via npm i -g and invocations via npx.

GitHub Actions currently only supports up to Node v20, so it hasn't seemed necessary to support higher versions (to be fair, though, I mainly use v22 when working on this tool).

I will make sure to update the docs and the package.json to reflect that v23 is not yet supported.

Am I missing something, or is this a bug? Given there are no JavaScript sources for the bootstrap script, how is this supposed to work with Node versions without type stripping support?

At the moment, it's not :( I will keep this issue open though and do some testing. My main concern with transpiling this project is what kind of issues are going to raise their head trying to support the different permutations of TypeScript, JavaScript, CommonJS, ESM, npm, pnmp, and yarn. I'm sure at least several heads on that hydra will refuse to cooperate...

[ncalteen]

Status Update:

It is possible to bundle via rollup (it does require tweaking/removing some packages @github/local-action uses currently, but nothing that would break the overall functionality. However, the main issue lies with supporting actions authored in TypeScript. It is entirely possible I am wrong, but I do not see a way to stub the functionality of specific modules from the transpiled action code. At least not one that would keep me sane...

Because of that, @github/local-action needs to run the main TypeScript files; it's TSConfig must have allowImportingTsExtensions set to true, which then requires noEmit be set to true as well :/