Insiders changes breaks some implementations of DocumentSymbolProvider

[DanTup]

The current version of Dart code's symbol provider works in Stable, but shows 0 results in Insiders.

I think this is because I'm not returning an instance of SymbolInformation but rather returning an object that implements the (previous?) interface.

I suspect this will be considered a bug of mine and I should be creating instances of SymbolInformation, however it's possible others have done this and the failures appears to be silent (I don't see any warnings that what I returned will not be used).

I think this has come up before - TypeScript is happy that my objects are the required type, but changes in Code sometimes fail if they're not real instances. I'm not sure what the official line is (or whether there's a TypeScript setting I can enable to warn when people do this?).

[jrieken]

TypeScript is happy that my objects are the required type, but changes in Code sometimes

Yeah, that some TypeScript weirdness as they don't consider the ctor being part of the structural identity... I'll see if I can make a change

[jrieken]

Hm, this actually shouldn't be an issue anymore. I have pushed 49323b3#diff-6ed04bc0a0e32b52bb98d493792f857e 12 days ago... @DanTup Do you recall with what version of insiders you have tried this?

[DanTup]

I don't, but my tests are still failing today on the CI (I run them on stable and insiders). LMK if you can't repro and I'll make a small code sample.

[DanTup]

Oops, ignore the comment about CI; I confused this with #50321 because opened both... I can re-test though. It's possible I was a few days out of date when I raised this - I will re-test.

[DanTup]

@jrieken If I roll back my fix I still see the issue on Insiders bfd155e.

Repros with this code:

public provideDocumentSymbols(document: TextDocument, token: CancellationToken): SymbolInformation[] {
	return [{
		containerName: "container",
		kind: SymbolKind.Method,
		location: {
			range: document.getWordRangeAtPosition(document.positionAt(0)),
			uri: document.uri,
		},
		name: "name",
	}];
}

[jrieken]

Yeah, there was another nested instanceof-check. Messy stuff... I have pushed a workaround that help for now. This code will likely undergo further changes when the API becomes stable