Don't use yarn internally

[dcousens]

this issue was transferred from https://github.com/keystonejs/keystone, but GitHub didn't like how I went from discussion(there)->discussion(here)->issue(this)

^{Originally posted by RodrigoNovais May 4, 2023}
I've run npm init keystone-app to setup a new environment and it's dependencies where installed with yarn without my consent.
Would be polite to ask the developers which manager they want to use.
I only have yarn installed in my machine cause I was obligated to use it in previours jobs and would like to avoid it as much as possible.
Since the dependencies where automatically installed via yarn I don't even know if the CLI can initiate a project in a setup with pure npm.

I don't think this is a matter of consent, as this is open source software - but we don't need to be using yarn specifically either, so it's something we could probably add support for if desired.

@RodrigoNovais pull requests are accepted 💛

[dcousens]

@RodrigoNovais the code falls back to npm if yarn isn't installed.

create-keystone-app/create-keystone-app/src/index.ts

Lines 50 to 67 in 780a3c6

	const installDeps = async (cwd: string): Promise<'yarn' | 'npm'> => {
	const spinner = ora(
	'Installing dependencies with yarn. This may take a few minutes.'
	).start();
	try {
	await execa('yarn', ['install'], { cwd });
	spinner.succeed('Installed dependencies with yarn.');
	return 'yarn';
	} catch (_err: any) {
	let err: ExecaError = _err;
	if (err.failed) {
	process.stdout.write('\n');
	spinner.warn('Failed to install with yarn.');
	spinner.start(
	'Installing dependencies with npm. This may take a few minutes.'
	);
	try {
	await execa('npm', ['install'], { cwd });

You could probably write up something that uses the process.env.npm_config_user_agent to determine what package manager is in use.

[RodrigoNovais]

I may not have been able to communicate correctly. I also think I was pretty rude in my first approach.

I think it would be nice if one of the options occurred:

• To ask the client which package manager they would like to use
• To handle the project with the same package manager the CLI was called with

I don't think I'm capable of implementing such thing but I'd like to know your opinion about it