Incorrect behavior when using alias refers to namespace in using alias · dotnet/roslyn#1027

(17 comments) (1 reaction) (0 assignees)C# (20,414 stars) (4,257 forks)batch import

Area-CompilersBughelp wanted

説明

extern alias Contracts1;
extern alias Contracts2;

using alias1 = Contracts1::TestContractAssembly;
using alias2 = Contracts2::TestContractAssembly;

partial class Contract : alias1.IContract, alias2.IContract
{
    int alias1.IContract.x
    {
        get
        {
            return 1;
        }
    }
    int alias2.IContract.x
    {
        get
        {
            return 1;
        }
    }
}

Both IContract types are the same - they expose an int property "x". Roslyn incorrectly reports that IContract.x has already been implemented.

This works if you inline the using aliases.

I strongly suspect that the alias points to the merged namespace symbol, rather than to the namespace symbol contained in the assembly symbol referenced by the extern alias.

コントリビューターガイド

技術スタック: csharp
領域: tooling
Issue 種別: bug
難度: 5
推定時間: over 1 week
活動状況: needs maintainer response
明確さ: clear
前提条件: C#Roslyn compiler internalsunderstanding of extern aliases
初心者向け度: 10
調査方針: Investigate the Roslyn source code related to namespace alias resolution. The issue suggests that alias references are incorrectly resolved to merged namespace symbols instead of assembly specific ones. Look at the SemanticModel or symbol resolution logic, likely in files like `Symbol.cs` or `NamespaceSymbol.cs`. Review comments in the issue for any suggested code paths. A fix would require ensuring that extern alias references maintain proper assembly boundaries when resolving namespaces.