node --check does not support ESM on Node.js 16

[matthewrobertson]

Version

v16.13.1

Platform

x86_64 GNU/Linux

Subsystem

No response

What steps will reproduce the bug?

Create a simple ESM script:

// foo.mjs
export function testFunction(req, res) {
  return 'PASS';
}

Then run:

node --check foo.mjs

How often does it reproduce? Is there a required condition?

100% of the time

What is the expected behavior?

check should allow ESM exports in files that have a .esm extensions or in projects that set "type": "module" in their package.json

What do you see instead?

node --check does respect the .mjs extension:

node --check foo.mjs
(node:2292833) Warning: To load an ES module, set "type": "module" in the package.json or use the .mjs extension.
(Use `node --trace-warnings ...` to show where the warning was created)
/usr/local/google/home/mattrobertson/gcf/functions-framework-nodejs/test/data/esm_mjs/foo.mjs:8
export function testFunction(req, res) {
^^^^^^

SyntaxError: Unexpected token 'export'
    at Object.compileFunction (node:vm:352:18)
    at wrapSafe (node:internal/modules/cjs/loader:1031:15)
    at checkSyntax (node:internal/main/check_syntax:66:3)
    at node:internal/main/check_syntax:39:3

Additional information

When using v14 the file checks fine:

nvm use 14 # => Now using node v14.18.1 (npm v6.14.15)
node --check foo.mjs

[Ayase-252]

It occurs since v16.12.0.

[targos]

It occurs since v16.12.0.

Changelog: https://github.com/nodejs/node/releases/tag/v16.12.0