aspnetcore: TopLevelParameterNameAnalyzer threw an exception of type System.NullReferenceException.

Describe the bug

The warning below is emitted when building my project.

CSC : warning AD0001: Analyzer 'Microsoft.AspNetCore.Mvc.Analyzers.TopLevelParameterNameAnalyzer' threw an exception of type 'System.NullReferenceException' with message 'Object reference not set to an instance of an object.'.

To Reproduce

Install .NET Core SDK 3.0.100.
git clone git@github.com:twitchax/AspNetCore.Proxy.git
dotnet test

Expected behavior

No warnings.

Screenshots

N/A.

Additional context

.NET Core SDK (reflecting any global.json):
 Version:   3.0.100
 Commit:    04339c3a26

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.18362
 OS Platform: Windows
 RID:         win10-x64
 Base Path:   C:\Program Files\dotnet\sdk\3.0.100\

Host (useful for support):
  Version: 3.0.0
  Commit:  7d57652f33

.NET Core SDKs installed:
  1.0.4 [C:\Program Files\dotnet\sdk]
  1.1.0-preview1-005051 [C:\Program Files\dotnet\sdk]
  1.1.0-preview1-005077 [C:\Program Files\dotnet\sdk]
  1.1.0-preview1-005098 [C:\Program Files\dotnet\sdk]
  1.1.0 [C:\Program Files\dotnet\sdk]
  2.0.0-preview1-005977 [C:\Program Files\dotnet\sdk]
  2.0.0-preview2-006497 [C:\Program Files\dotnet\sdk]
  2.0.0 [C:\Program Files\dotnet\sdk]
  2.0.2-vspre-006949 [C:\Program Files\dotnet\sdk]
  2.0.2 [C:\Program Files\dotnet\sdk]
  2.1.1-preview-007094 [C:\Program Files\dotnet\sdk]
  2.1.1-preview-007165 [C:\Program Files\dotnet\sdk]
  2.1.1 [C:\Program Files\dotnet\sdk]
  2.1.2 [C:\Program Files\dotnet\sdk]
  2.1.4 [C:\Program Files\dotnet\sdk]
  2.1.100-preview-007326 [C:\Program Files\dotnet\sdk]
  2.1.100-preview-007363 [C:\Program Files\dotnet\sdk]
  2.1.100 [C:\Program Files\dotnet\sdk]
  2.1.200-preview-007474 [C:\Program Files\dotnet\sdk]
  2.1.200-preview-007597 [C:\Program Files\dotnet\sdk]
  2.1.200 [C:\Program Files\dotnet\sdk]
  2.1.201 [C:\Program Files\dotnet\sdk]
  2.1.202 [C:\Program Files\dotnet\sdk]
  2.1.301 [C:\Program Files\dotnet\sdk]
  2.1.400-preview-009171 [C:\Program Files\dotnet\sdk]
  2.1.402 [C:\Program Files\dotnet\sdk]
  2.1.600-preview-009426 [C:\Program Files\dotnet\sdk]
  2.1.600-preview-009472 [C:\Program Files\dotnet\sdk]
  2.1.602 [C:\Program Files\dotnet\sdk]
  2.2.102 [C:\Program Files\dotnet\sdk]
  2.2.401 [C:\Program Files\dotnet\sdk]
  3.0.100 [C:\Program Files\dotnet\sdk]

.NET Core runtimes installed:
  Microsoft.AspNetCore.All 2.1.1 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.6 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.7 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.9 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.13 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.2.1 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.2.6 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.App 2.1.1 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.6 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.7 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.9 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.13 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.2.1 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.2.6 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.0.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 1.0.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 1.1.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.0.0-preview1-002111-00 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.0.0-preview2-25407-01 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.0.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.0.3 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.0.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.0.6 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.0.7 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.0.9 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.1 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.4 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.6 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.7 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.9 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.13 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.2.1 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.2.6 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.0.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 3.0.0 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

About this issue

Original URL
State: closed
Created 5 years ago
Reactions: 8
Comments: 17 (5 by maintainers)

Most upvoted comments

I have the same problem after migration to core 3, visual studio is 16.3.7

+14

Shiko1st on Oct 31, 2019

Without disabling the Code Analysis (Project Settings > Code Analysis > Run On Build) this error prevents my project from building in Visual Studio.

VS version: 16.3.9 .NET Core SDK: 3.0.100

As you can see my project after upgrading from .net core 2.2 to 3.0 has references to two different versions of Microsoft.AspNetCore.Mvc.Analyzers

+12

yuchen-w on Nov 20, 2019

@twitchax the test app is using a 3.0.0 of Microsoft.AspNetCore.TestHost which is effectively lifting the tests to compile the app against 3.0.0 versions of ASP.NET Core. Your app is still targeting .NET Core 2.2. Given there were many breaking changes in 3.0, I don’t think you want to mix the two versions when testing.

Consider changing the test app to target 2.2.x version of TestHost or migrating your application to .NET Core 3.0. Alternatively, you should be able to suppress the analyzer in the test project.

More details: The null refs is a result of one of the breaking changes in 3.0 - some types that were formerly pub-internal were moved to a public interface while also changing their namespace. The app’s package reference to Microsoft.AspNetCore.Mvc to 2.2.0 gets lifted to the 3.0.0 framework reference in the test app, but the analyzer package remains 2.2.0. You effectively get this:

This might fall in to the category of the SDK lifting the 2.2 analyzer package reference to a 3.0 version if it sees a FrameworkReference to Microsoft.AspNetCore.App, but I’m not sure how trivial that is.

pranavkm on Oct 4, 2019

Closing this as there are no follow-up items left here. If you hit this issue, read @pranavkm 's comment above: https://github.com/dotnet/aspnetcore/issues/14723#issuecomment-588389938

mkArtakMSFT on May 21, 2020

@OwenPattison Yes, I have noted that the issue is that code analysis by default does generate the issue by the way it is configured. 2 options: The first remove the checkboxes, the default is checked and what it installs does not work

The 2nd Install FxCop package and then update to the new version, no clue why it isn’t installing a updated version to start with

PeterPann23 on Feb 19, 2020

I am also seeing the same issue after upgrading to dotnet core 3.1.101.

@PeterPann23 were you able to resolve your issue, I’m also interested in how you established it was introduced via an entity framework dll? so that I could potentially track down where my issue lies.

OwenPattison on Feb 19, 2020

@yuchen-w You probably have nuget package which have 2.2.0 as dependency, like:

devenv_2019-11-26_21-16-53

sm-g on Nov 26, 2019