Inconsistent coloring of interface inheriting IDisposable

[kerams]

The problem is here

fsharp/src/Compiler/Service/SemanticClassification.fs

Lines 311 to 329 in d441308

	| Item.Types (_, ty :: _), LegitTypeOccurence, m ->
	let ty = stripTyEqns g ty
	if isDisposableTy g amap ty then
	add m SemanticClassificationType.DisposableType
	else
	match tryTcrefOfAppTy g ty with
	| ValueSome tcref -> add m (reprToClassificationType g tcref.TypeReprInfo tcref)
	| ValueNone ->
	if isStructTupleTy g ty then
	add m SemanticClassificationType.ValueType
	elif isRefTupleTy g ty then
	add m SemanticClassificationType.ReferenceType
	elif isForallFunctionTy g ty then
	add m SemanticClassificationType.Function
	elif isTyparTy g ty then
	add m SemanticClassificationType.ValueType
	else
	add m SemanticClassificationType.TypeDef

We check for a disposable type first.

Expected behavior

IConn in source code should be classified as an interface. Or perhaps the tooltip coloring should be changed?

Actual behavior

IConn in source code is classified as a disposable type. IConn in tooltip is classified as an interface.

[majocha]

Tooltips use TextTag type for colorization, not SemanticClassificationType. Unfortunately there is no one-to-one mapping between those. That's why tooltips entirely miss some semantic colors for mutability, disposable value / type etc.
IIRC tooltip text generation and tagging happens mostly in NicePrint.fs.