expressions: ERR_MODULE_NOT_FOUND attempting to run example demo script

[dekimsey]

Describe the bug
The instructions for running the demo don't seem to work. While I'm pretty sure it's user error, it's not clear how to address this. Especially from within the runtime context of a @actions/github-script.

To Reproduce
Steps to reproduce the behavior:

1. npm install @actions/expressions
2. copy example code block, simple example to a file (note: it's not obvious, but it appears it must be in a mjs file as it uses imports keyword)
3. run with: node ./example.mjs.

Expected behavior
A testable example.

Screenshots

$ npm install @actions/expressions
$ vim example.mjs
...
$ node example.mjs
node:internal/modules/esm/resolve:264
    throw new ERR_MODULE_NOT_FOUND(
          ^

Error [ERR_MODULE_NOT_FOUND]: Cannot find module '/private/var/folders/j0/_6v6ffj54qs0wrl91bz5tbw40000gp/T/tmp.mvxT5dPk/node_modules/@actions/expressions/dist/ast' imported from /private/var/folders/j0/_6v6ffj54qs0wrl91bz5tbw40000gp/T/tmp.mvxT5dPk/node_modules/@actions/expressions/dist/index.js
    at finalizeResolution (node:internal/modules/esm/resolve:264:11)
    at moduleResolve (node:internal/modules/esm/resolve:917:10)
    at defaultResolve (node:internal/modules/esm/resolve:1130:11)
    at ModuleLoader.defaultResolve (node:internal/modules/esm/loader:396:12)
    at ModuleLoader.resolve (node:internal/modules/esm/loader:365:25)
    at ModuleLoader.getModuleJob (node:internal/modules/esm/loader:240:38)
    at ModuleWrap.<anonymous> (node:internal/modules/esm/module_job:85:39)
    at link (node:internal/modules/esm/module_job:84:36) {
  code: 'ERR_MODULE_NOT_FOUND',
  url: 'file:///private/var/folders/j0/_6v6ffj54qs0wrl91bz5tbw40000gp/T/tmp.mvxT5dPk/node_modules/@actions/expressions/dist/ast'
}

Node.js v21.4.0

Package/Area

• Expressions
• Workflow Parser
• Language Service
• Language Server

Package Version
v0.3.8

Additional context

I really just want to access this module from within a @actions/github-script step but for the life of me I haven't been able to figure out how to do that. With other NPM installed modules it was some variation of an import directive. However, this one just doesn't work. So I tried just replicating exactly what is documented in this project to check my assumptions. Which is how I came to this point.

I'll be honest, this could very well be user error. Undoubtedly further complicated by my personal lack of familiarity with the state of module/script vs require/imports in Node. But struggle as I may, I cannot figure out how to import this module into a script to run.

Very likely related to #50.

Thank you

[JoshuaKGoldberg]

Here's a quick standalone reproduction: https://github.com/JoshuaKGoldberg/repros/tree/actions-workflow-parser-module-import-issues

Related to #50 indeed.

[lavaude]

Any workaround found so far?

[ericsciple]

Should be fixed with PR:

• ESM migration: Add .js extensions for node16 moduleResolution #257

Please reopen if not.