clearScreen: 'update'

[Rich-Harris]

Description

If a plugin logs something to the console, the logs are destroyed as soon as the welcome text appears...

  VITE v3.0.0  ready in 243 ms

  ➜  Local:   http://127.0.0.1:5174/
  ➜  Network: use --host to expose

...unless you use clearScreen: false — in other words, potentially critical logs are hidden by default. Of course, there's a good reason why clearScreen: true is the default; setting it to false is often undesirable.

It's possible to work around this — in SvelteKit we're doing this...

const print_urls = vite.printUrls;
vite.printUrls = function () {
  print_urls.apply(this);
  if (deferred_warning) console.error('\n' + deferred_warning);
};

...but that only works for that deferred_warning; adding new stuff involves more plumbing, and can never cover arbitrary other plugins unless we monkey-patch console which is brittle and hacky. It's also clearly not an individual plugin's responsibility.

Suggested solution

It would be nice if we had a hybrid solution — don't clear the screen initially, but do clear it after updates. Something like this:

clearScreen: 'update'

I'd personally love it if this was the default, and I'd go so far as to argue that it's not a breaking change, though others might feel differently about that last part.

Alternative

The name 'update' is definitely bikesheddable.

Additional context

No response

Validations

• Follow our Code of Conduct
• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that request the same feature to avoid creating a duplicate.

[sapphi-red]

It seems Vite already does this as long as config.logger.warn/warnOnce/error is used.

vite/packages/vite/src/node/cli.ts

Lines 112 to 117 in 45d6797

	info(
	`\n ${colors.green(
	`${colors.bold('VITE')} v${VERSION}`
	)} ${startupDurationString}\n`,
	{ clear: !server.config.logger.hasWarned }
	)

vite/packages/vite/src/node/logger.ts

Lines 110 to 128 in 45d6797

	const logger: Logger = {
	hasWarned: false,
	info(msg, opts) {
	output('info', msg, opts)
	},
	warn(msg, opts) {
	logger.hasWarned = true
	output('warn', msg, opts)
	},
	warnOnce(msg, opts) {
	if (warnedMessages.has(msg)) return
	logger.hasWarned = true
	output('warn', msg, opts)
	warnedMessages.add(msg)
	},
	error(msg, opts) {
	logger.hasWarned = true
	output('error', msg, opts)
	},

[benmccann]

Oops. I didn't mean to close this

[bluwy]

Update from the last time we discussed in the meetings: ideally we want this to be the default instead of another option value.