Need a hook or event to set process.env before _parseOptionsEnv

[hungtcs]

Hallo,
Is there any way to set environment variables before _parseOptionsEnv function?
my use case is to read .env file via dotenv and set environment variables before all subcommands are executed.

The dotenv file can be specified, and I am use enablePositionalOptions to process options.
The issue is preAction hook are emit after _parseOptionsEnv function, this will cause new Option().env('SOME_ENV') not to perform as expected.

program.addOption(new Option('--env <env>', 'env file').default('.env'))
  .hook('preAction', async () => {
    const { env } = program.opts();
    dotenv.config({ path: env, override: true });
  });

I also tried the option:env event, but it doesn't solve the problem perfectly either.

I searched relevant issues and stackoverflow as much as possible, but no solution found.

Thanks.

[hungtcs]

It may be a preSubCommand hook that performs some async operations before sub command parsing

[shadowspawn]

I also tried the option:env event, but it doesn't solve the problem perfectly either.

For interest, what didn't work using the option:env approach? (It does not support async?)

[hungtcs]

I also tried the option:env event, but it doesn't solve the problem perfectly either.

For interest, what didn't work using the option:env approach? (It does not support async?)

In my use case, async support is not necessary.

program.addOption(new Option('--env <env>', 'env file').default('.env'))
  .on('option:env', () => {
    console.log('option:env event emit');
  });

This event will only fire when the env parameter is explicitly specified, default value does not trigger the event.

node dist/main.js --env .env.production  # trigger
node dist/main.js  # default value .env not trigger

[shadowspawn]

Released in Commander v9.4.0