export default async function foo() {} does not declare foo

[mroch]

Bug Report

Current Behavior

export default async function foo() { return "foo" }
foo().then(console.log)

in node 10.10 with --experimental-modules, this logs "foo". in babel 7.0.0, it says foo is not defined.

Expected behavior/code
I think foo should be in scope.

it's in scope if you remove async. the spec has the same rules for all ExportDeclaration: export default HoistableDeclaration productions, which also leads me to believe that if it's in scope for non-async functions, it should work the same for async functions as well.

Babel Configuration (.babelrc, package.json, cli command)

  ["@babel/plugin-transform-regenerator", {
      "asyncGenerators": false,
      "generators": false,
      "async": false
  }]

Environment

• Babel version(s): v7.0.0
• Node/npm version: 10.10
• OS: macOS 10.13.6
• How you are using Babel: cli

[babel-bot]

Hey @mroch! We really appreciate you taking the time to report an issue. The collaborators
on this project attempt to help as many people as possible, but we're a limited number of volunteers,
so it's possible this won't be addressed swiftly.

If you need any help, or just have general Babel or JavaScript questions, we have a vibrant Slack
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for an invite.

[nicolo-ribaudo]

What is the code generated by Babel? You are disabling the async functions transform ("async": false), so Babel desn't transpile that function.

[babel-bot]

Hi @mroch! A maintainer of the project has notified me that you're missing
some information we'll need to replicate this issue.

Please understand that we receive a high volume of issues, and there are only a limited number
of volunteers that help maintain this project. The easier it is for us to decipher an issue with the info provided,
the more likely it is that we'll be able to help.

Please make sure you have the following information documented in this ticket:

1. Your Babel configuration (typically in the form of a .babelrc)
2. The current (incorrect) behavior you're seeing
3. The behavior you expect
4. A short, self-contained example

Please provide either a link to the problem via the repl, or if the repl is insufficient,
a new and minimal repository with instructions on how to build/replicate the issue.

[danez]

I just tested this and I'm not able to reproduce this. If it is still a problem please reopen and provide an example that triggers the error.