PR: Fix enabling/disabling individual providers (Completions)

[dalthviz]

Description of Changes

The start and shutdown providers logic was missing updating the language_status attribute which is used to determine the providers that are available for a certain language. In the case of a completion request all responses for the available providers need to be aggregated, so all providers need to be waited before a response is made available. This caused that by disabling one of the providers no reponse was able to be retrieved but still that provider was expected to give a reponse

Also, there is some logic to handle a timeout but only the LSP provider is marked as slow and at least 3 providers need to be marked as slow to trigger the logic. For more details about that see:

spyder/spyder/plugins/completion/plugin.py

Lines 1038 to 1044 in 6d53101

	# Start the timer on this request
	if req_type in self.AGGREGATE_RESPONSES and slow_provider_count > 2:
	if self.wait_for_ms > 0:
	QTimer.singleShot(self.wait_for_ms,
	lambda: self.receive_timeout(req_id))
	else:
	self.requests[req_id]['timed_out'] = True

Issue(s) Resolved

Fixes #21462

Affirmation

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and understand I am releasing the same under Spyder's MIT (Expat) license.

I certify the above statement is true and correct: dalthviz

[ccordoba12]

Thanks @dalthviz for quickly finding the solution to this serious problem. For now I'm just going to leave a quick note to say that the failures in our tests on Windows are unrelated to this and I'll try to fix them tomorrow.

[ccordoba12]

@dalthviz, please rebase on top of 5.x to get the changes I did in PR #21467 to fix our tests.

Also, there is some logic to handle a timeout but only the LSP provider is marked as slow and at least 3 providers need to be marked as slow to trigger the logic.

I suggest to leave that for Spyder 6 so we can think more carefully about it. What do you think?

[ccordoba12]

Looks good to me, thanks @dalthviz!