fix: no complete keyword colons before colons

[A4-Tacks]

Related #22479

Example

fn foo() { $0::bar }

Before this PR

fn foo() { self::::bar }

After this PR

fn foo() { self::bar }

[ChayimFriedman2]

I think the label should also not include ::.

View changes since this review

[A4-Tacks]

I think the label should also not include ::.

This will be difficult to distinguish between self (local) and self:: (module)

[ChayimFriedman2]

Given they complete exactly the same, I don't think we should show both.

[A4-Tacks]

Users can choose whether to complete the colons by selecting the completion item, This feature should not be compromised

[ChayimFriedman2]

What I mean is, when we do not complete colons we should not show both.

[A4-Tacks]

Cases that do not complete the colons seem to only occur before the colons

This should be irrelevant

[ChayimFriedman2]

There, or when the user opted out in the settings. In both cases it's confusing that colons are shown but not completed.

[A4-Tacks]

There

This is irrelevant because colons is exists

or when the user opted out in the settings. In both cases it's confusing that colons are shown but not completed.

Colons shown and completed

My consideration for this is:
When users want to completely return to their old behavior by changing settings, not completing :: will break, but perhaps this is a good thing?

[A4-Tacks]

fn main() {
    s$0
    s$0::bar
}

Old: self:: self::
New: self:: self
New addColonsToModule: false: self:: self
New addColonsToModule: false: self self (perhaps this is better?)

[ChayimFriedman2]

Your table of behaviors is correct. The only thing I said is that when we don't complete the colons, we should not show them in the label either, and that when we do that and also have a self completion, we should not show both since it's the same completion.

[A4-Tacks]

The only thing I said is that when we don't complete the colons, we should not show them in the label either,

This will make it difficult to distinguish between local and module in both user and testing scenarios

and that when we do that and also have a self completion, we should not show both since it's the same completion.

This is difficult to implement and has little impact

Although the completion content is the same, CompletionRelevance is different