dotnet/roslyn
Voir sur GitHubUnexpected diagnostic in `with` expression with indexer on a struct
Open
#81 666 ouverte le 12 déc. 2025
Area-CompilersConcept-Diagnostic Clarityhelp wanted
Métriques du dépôt
- Stars
- (20 414 stars)
- Métriques de merge PR
- (Merge moyen 6j 17h) (256 PRs mergées en 30 j)
Description
Although this is an error scenario, the first diagnostic is unexpected.
[Fact]
public void TODO2()
{
var src = """
var c = new S() with { [0] = 1 };
public struct S
{
public int this[int i] { set { } }
}
""";
CreateCompilation(src).VerifyEmitDiagnostics(
// (1,24): error CS0131: The left-hand side of an assignment must be a variable, property or indexer
// var c = new S() with { [0] = 1 };
Diagnostic(ErrorCode.ERR_AssgLvalueExpected, "[0]").WithLocation(1, 24),
// (1,24): error CS0747: Invalid initializer member declarator
// var c = new S() with { [0] = 1 };
Diagnostic(ErrorCode.ERR_InvalidInitializerElementInitializer, "[0] = 1").WithLocation(1, 24));
}