Roslyn doesn't take into account [DoesNotReturn] annotations on accessors #50018
Description
Version Used:
Branch master (8 Dec 2020)
Latest commit 60d947d by AlekseyTs:
Ensure that each generic local function gets its own container to cache dynamic call-sites. (#49802)
Fixes #49599.
Steps to Reproduce:
#nullable enable
using System.Diagnostics.CodeAnalysis;
public class Base
{
public virtual string? P { [DoesNotReturn] get { throw null!; } [DoesNotReturn] set { throw null!; } }
void Test()
{
P = null;
P?.ToString();
P.ToString(); // false CS8602
}
}
Expected Behavior:
No warnings in the Test method. The method won't execute after the first set accessor is executed
Actual Behavior:
No warnings. Roslyn completely ignores the [DoesNotReturn] annotations and thinks the method can continue.
Notes
Roslyn allows these annotations and even verifies them for inheritance so I think it should take them into account in the nullability analysis as well
#nullable enable
using System.Diagnostics.CodeAnalysis;
public class Base
{
public virtual string? P { [DoesNotReturn] get { throw null!; } [DoesNotReturn] set { throw null!; } }
}
public class Derived : Base
{
public override string P {
get { throw null!; } // CS8770: Method 'string Derived.P.get' lacks `[DoesNotReturn]` annotation to match implemented or overridden member.
set { throw null!; } // CS8770: Method 'void Derived.P.set' lacks `[DoesNotReturn]` annotation to match implemented or overridden member.
}
}
Note: This issue is referenced in source