HOW-TO: ES Modules with @std/esm

[motss]

If you're using @std/esm for your projects, ava will not be able to read your import test from 'ava'; if you're not transpiling ES modules.

The following configuration in package.json will help you out:

{
...
"@std/esm": {
  "esm": "all",
  "cjs": true,
  "gz": true,
  "await" true
},
"ava": {
  "require": [
    "@std/esm"
  ]
}
...
}

Hope this helps! 🎉

[sindresorhus]

@motss Would you be able to submit a recipe?

See: https://github.com/avajs/ava/tree/master/docs/recipes

[motss]

@sindresorhus PTAL at the PR #1593

[dacz]

It doesn't work for me. I use flow so my .babelrc:

{
  "presets": ["@babel/preset-flow"]
}

and package.json

...
"@std/esm": { "esm": "all", "cjs": true },
  "ava": {
    "files": ["**/**/*.test.js"],
    "require": ["@std/esm", "@babel/register"],
    "babel": {
      "babelrc": true
    }
  },
...

I tried all possible combinations in require section of ava and in @std/esm settings.

Outside ava `@std/esm works like a charm. And w/o @std/esm ava works (with some limitations based on babel7).

[jdalton]

@dacz head over to the @std/esm repo and file the issue there with a simple repro repo and I'll investigate.

[motss]

@dacz Thanks for reporting the issue. Are you using Babel 6 or 7? Mind filing an issue at @std/esm as @jdalton suggested with your Babel config to assist in the investigation?

[jdalton]

It looks like there was complications with ava support for test files.
See standard-things/esm#197 (comment).

Packages using @std/esm still work with ava.
It's just that ava handles ESM tightly on test files at the moment. Related to #709.