dotnet/roslyn

VB SemanticModel fails to bind type argument inside cref even though compiler produces no error

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#2,197 建立於 2015年4月23日

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描述

The C# compiler (SemanticModel) correctly returns a TypeParameter symbol for the U in <see cref="C{U}"/> in the below example. I can validate this in the syntax visualizer (see below screenshot) and this also works via API (for example if I get symbol for C{U} and inspect its symbol.TypeArguments. capture

For the corresponding case in VB, U does not bind (see below screenshot). If I get symbol for C(Of U) and inspect its symbol.TypeArguments, I get back a ErrorTypeSymbol. capture2

Shouldn't the VB compiler be able to return a valid symbol in the above case (considering that the code didn't produce any errors)? Why do the two compilers behave differently here.

貢獻者指南

技術棧
csharp
領域
tooling
議題類型
bug
難度面向新貢獻者的預計實作難度，1 表示很小改動，5 表示專家級工作。
4
預計時間有經驗貢獻者完成調查、實作、測試並準備 pull request 的粗略時間範圍。
over 1 week
活動狀態議題目前的可參與程度：新鮮、活躍、陳舊、阻塞或等待維護者輸入。
stale
清晰度議題是否清楚說明預期改動、驗收標準和下一步。
clear
前置要求
C# and VB basicsRoslyn SemanticModelCompiler binding concepts
新手友善度1-100 的估計分數，表示該議題對首次貢獻者的友善程度。
15
研究方向
Investigate the VB compiler's implementation of cref binding in documentation comments. Compare with the C# compiler's handling in the same area. Look at the SemanticModel methods for resolving type arguments in crefs. Check if the VB compiler has a similar code path for C(Of U) as C# does for C<U>. The issue's screenshots show the difference in the syntax visualizer, so start by examining the VB syntax tree for the cref and see where binding fails. Also search for any existing tests related to cref binding in VB.
VB SemanticModel fails to bind type argument inside cref even though compiler produces no error · dotnet/roslyn#2197 | Good First Issue