Error CS0229 : Ambiguity on partial props with primary constructor

[jasonmsmith]

Describe the bug

The error occurs in a very specific situation:

1. The class must contain at least one partial property. (In my tests, the definition and implementation were in separate files)
2. The class must have a primary constructor
3. Use the nameof operator to refer to one of the partial properties of the class from the constructor of an attribute attached to a class. (It is important that the nameof operator is used outside of any class definitions. nameof works as expected inside the bounds of a class definition.)

When these three conditions are met, dotnet build fails with Error CS0229, claiming ambiguity between the two halves of the partial property.

To Reproduce

You can see a simple class library here: https://github.com/jasonmsmith/PartialPropertyTest

Note that there are two nearly identical classes, one with a standard constructor and the other with a primary constructor. The one with a primary constructor causes an error on build, but not the one with a standard constructor.

Exceptions (if any)

N/A

Further technical details

dotnet --info
.NET SDK:
Version: 9.0.101
Commit: eedb237549
Workload version: 9.0.100-manifests.1e472b70
MSBuild version: 17.12.12+1cce77968

Runtime Environment:
OS Name: Windows
OS Version: 10.0.22631
OS Platform: Windows
RID: win-x64
Base Path: C:\Program Files\dotnet\sdk\9.0.101\

.NET workloads installed:
[android]
Installation Source: SDK 9.0.100, VS 17.9.34723.18
Manifest Version: 35.0.24/9.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\9.0.100\microsoft.net.sdk.android\35.0.24\WorkloadManifest.json
Install Type: Msi

[ios]
Installation Source: SDK 9.0.100, VS 17.9.34723.18
Manifest Version: 18.2.9170/9.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\9.0.100\microsoft.net.sdk.ios\18.2.9170\WorkloadManifest.json
Install Type: Msi

[maccatalyst]
Installation Source: SDK 9.0.100, VS 17.9.34723.18
Manifest Version: 18.2.9170/9.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\9.0.100\microsoft.net.sdk.maccatalyst\18.2.9170\WorkloadManifest.json
Install Type: Msi

[maui-windows]
Installation Source: SDK 9.0.100, VS 17.9.34723.18
Manifest Version: 9.0.0/9.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\9.0.100\microsoft.net.sdk.maui\9.0.0\WorkloadManifest.json
Install Type: Msi

Configured to use loose manifests when installing new manifests.

Host:
Version: 9.0.0
Architecture: x64
Commit: 9d5a6a9aa4

.NET SDKs installed:
8.0.202 [C:\Program Files\dotnet\sdk]
8.0.404 [C:\Program Files\dotnet\sdk]
9.0.101 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
Microsoft.AspNetCore.App 6.0.28 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 7.0.17 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 8.0.3 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 8.0.11 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 9.0.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 6.0.28 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 7.0.17 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 8.0.3 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 8.0.11 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 9.0.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 6.0.28 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 7.0.17 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 8.0.3 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 8.0.11 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 9.0.0 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

Other architectures found:
x86 [C:\Program Files (x86)\dotnet]
registered at [HKLM\SOFTWARE\dotnet\Setup\InstalledVersions\x86\InstallLocation]

Environment variables:
Not set

global.json file:
Not found

Learn more:
https://aka.ms/dotnet/info

Download .NET:
https://aka.ms/dotnet/download

• The IDE (VS / VS Code/ VS4Mac) you're running on, and its version: Jetbrains Rider 2024.3.3. However, the issue persists when running dotnet build from the command line.

[KalleOlaviNiemitalo]

This is similar to #76651; not exactly the same, but might have the same root cause.