Are two implementations of documentation comment ID generator necessary?

[svick]

There are two ways to get a documentation comment ID for an ISymbol:

1. DocumentationCommentId.CreateDeclarationId/DocumentationCommentId.CreateReferenceId
2. ISymbol.GetDocumentationCommentId

These two approaches have separate implementations, for example:

roslyn/src/Compilers/Core/Portable/DocumentationCommentId.cs

Lines 418 to 441 in 374ee31

	public override bool VisitMethod(IMethodSymbol symbol)
	{
	if (this.Visit(symbol.ContainingSymbol))
	{
	_builder.Append(".");
	_builder.Append(EncodeName(symbol.Name));
	}
	if (symbol.TypeParameters.Length > 0)
	{
	_builder.Append("``");
	_builder.Append(symbol.TypeParameters.Length);
	}
	AppendParameters(symbol.Parameters);
	if (!symbol.ReturnsVoid)
	{
	_builder.Append("~");
	this.GetReferenceGenerator(symbol).Visit(symbol.ReturnType);
	}
	return true;
	}

roslyn/src/Compilers/CSharp/Portable/DocumentationComments/DocumentationCommentIDVisitor.PartVisitor.cs

Lines 99 to 123 in 374ee31

	public override object VisitMethod(MethodSymbol symbol, StringBuilder builder)
	{
	Visit(symbol.ContainingType, builder);
	builder.Append('.');
	builder.Append(GetEscapedMetadataName(symbol));
	if (symbol.Arity != 0)
	{
	builder.Append("``");
	builder.Append(symbol.Arity);
	}
	if (symbol.Parameters.Any() || symbol.IsVararg)
	{
	s_parameterOrReturnTypeInstance.VisitParameters(symbol.Parameters, symbol.IsVararg, builder);
	}
	if (symbol.MethodKind == MethodKind.Conversion)
	{
	builder.Append('~');
	s_parameterOrReturnTypeInstance.Visit(symbol.ReturnType, builder);
	}
	return null;
	}

Is it necessary to have two separate implementations that do very similar things, or could they be consolidated into one?

Note that even on this small sample, some differences are visible:

• One uses MS.CA.IMethodSymbol, the other MS.CA.CS.Symbols.MethodSymbol.
• The condition for when return type is output are different. E.g. for int M() in class C, one returns M:C.M~System.Int32, the other one just M:C.M. Even if such differences are intentional and should be preserved, consolidating the two implementations could still make sense.

[CyrusNajmabadi]

Definitely seems odd. Would prefer we unify on the form used by the compiler today.