TopLevelParameterNameAnalyzer threw an exception of type 'System.NullReferenceException'

[fuocor]

Describe the bug

dotnet build throws using 3.0.100-preview4-010911 of the sdk
Microsoft.AspNetCore.Mvc.Analyzers.TopLevelParameterNameAnalyzer threw an exception of type 'System.NullReferenceException'

To Reproduce

on my builds

Expected behavior

should build

Additional context

I attached the diagnostic build logs and dotnet --info

build.zip
ditnet.info.txt

[pranavkm]

Thanks for the report. We addressed this as part of #8403. If you get the most recent SDK (3.0.100-preview4-010913), the issue should be resolved.

[spydacarnage]

@pranavkm

I've just download SDK (3.0.100-preview4-011223) and I am now also getting this NRE - has something reverted?

[pranavkm]

@spydacarnage not that I know of. I'll reopen this issue for investigation.

[spydacarnage]

Thanks

[Enngage]

I'm getting the same on Preview 5, but as warning and it does not prevent me from building the app:

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.'.

[pranavkm]

Thanks @Enngage. I think I sorted out of the last null refs from this analyzer.

[hellfirehd]

I'm still getting this with v3.0.100-preview6-012264:

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.'.

This is no global.json in use.

D:\Source> dotnet --info
.NET Core SDK (reflecting any global.json):
 Version:   3.0.100-preview6-012264
 Commit:    be3f0c1a03

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-preview6-012264\

Host (useful for support):
  Version: 3.0.0-preview6-27804-01
  Commit:  fdf81c6faf

.NET Core SDKs installed:
  2.1.700 [C:\Program Files\dotnet\sdk]
  2.1.800-preview-009677 [C:\Program Files\dotnet\sdk]
  2.1.800-preview-009696 [C:\Program Files\dotnet\sdk]
  2.2.300 [C:\Program Files\dotnet\sdk]
  3.0.100-preview6-012264 [C:\Program Files\dotnet\sdk]

.NET Core runtimes installed:
  Microsoft.AspNetCore.All 2.1.11 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.2.5 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.App 2.1.11 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.2.5 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.0.0-preview6.19307.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 2.1.11 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.2.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.0.0-preview6-27804-01 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 3.0.0-preview6-27804-01 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

To install additional .NET Core runtimes or SDKs:
  https://aka.ms/dotnet-download

What else can I provide to help troubleshoot this?

[pranavkm]

@hellfirehd do you happen to have the stack trace for this? Also, does this reproduce with a specific app? If so could you share it?

[hellfirehd]

I don't know how to get a Stack Trace from inside Visual Studio 2019 Community but it only happens during build, but on several different projects.

https://gist.github.com/hellfirehd/9720846be7aa1880f794861921f3c03a

I'm willing to share the Source Code/Project Files for Project1.txt

[pranavkm]

I'm willing to share the Source Code/Project Files for Project1.txt

That would be great!

[hellfirehd]

@pranavkm How do I get it to you? It's a .zip

[pranavkm]

Could you publish it as a GitHub repo? I think GitHub might also allow you to attach zip files to comments.

[hellfirehd]

Invite sent.

[pranavkm]

Your netcoreapp3.0 application is referencing 2.2 versions of packages which is unsupported. Have a look at https://docs.microsoft.com/en-us/aspnet/core/migration/22-to-30?view=aspnetcore-2.2&tabs=visual-studio for migrating to 3.0.

[sunildixit]

I am still seeing this issue.

Here's the stack trace

Severity Code Description Project File Line Suppression State Detail Description
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.'. ConnectorApp.Web 1 Active Analyzer 'Microsoft.AspNetCore.Mvc.Analyzers.TopLevelParameterNameAnalyzer' threw the following exception:

Exception occurred with following context:
Compilation: ConnectorApp.Web
ISymbol: Create (Method)
System.NullReferenceException: Object reference not set to an instance of an object.
at Microsoft.CodeAnalysis.CodeAnalysisExtensions.IsAssignableFrom(ITypeSymbol source, ITypeSymbol target)
at Microsoft.CodeAnalysis.CodeAnalysisExtensions.d__2.MoveNext()
at Microsoft.CodeAnalysis.CodeAnalysisExtensions.d__4.MoveNext()
at System.Linq.Enumerable.Any[TSource](IEnumerable1 source) at Microsoft.AspNetCore.Mvc.Analyzers.TopLevelParameterNameAnalyzer.<>c__DisplayClass3_0.<InitializeWorker>b__0(SymbolAnalysisContext symbolAnalysisContext) at Microsoft.CodeAnalysis.Diagnostics.AnalyzerExecutor.<>c.<ExecuteSymbolActionsCore>b__43_1(ValueTuple2 data)
at Microsoft.CodeAnalysis.Diagnostics.AnalyzerExecutor.ExecuteAndCatchIfThrows_NoLock[TArg](DiagnosticAnalyzer analyzer, Action1 analyze, TArg argument, Nullable1 info)

[spydacarnage]

What version of Core, VS2019, etc. are you using? I had the problem as well, but it went away weeks ago after an upgrade.

…

On Tue, 6 Aug 2019, 18:26 Sunil Dixit, ***@***.***> wrote: I am still seeing this issue. Here's the stack trace Severity Code Description Project File Line Suppression State Detail Description 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.'. ConnectorApp.Web 1 Active Analyzer 'Microsoft.AspNetCore.Mvc.Analyzers.TopLevelParameterNameAnalyzer' threw the following exception: 'Exception occurred with following context: Compilation: ConnectorApp.Web ISymbol: Create (Method) System.NullReferenceException: Object reference not set to an instance of an object. at Microsoft.CodeAnalysis.CodeAnalysisExtensions.IsAssignableFrom(ITypeSymbol source, ITypeSymbol target) at Microsoft.CodeAnalysis.CodeAnalysisExtensions.d__2.MoveNext() at Microsoft.CodeAnalysis.CodeAnalysisExtensions.d__4.MoveNext() at System.Linq.Enumerable.Any[TSource](IEnumerable1 source) at Microsoft.AspNetCore.Mvc.Analyzers.TopLevelParameterNameAnalyzer.<>c__DisplayClass3_0.<InitializeWorker>b__0(SymbolAnalysisContext symbolAnalysisContext) at Microsoft.CodeAnalysis.Diagnostics.AnalyzerExecutor.<>c.<ExecuteSymbolActionsCore>b__43_1(ValueTuple2 data) at Microsoft.CodeAnalysis.Diagnostics.AnalyzerExecutor.ExecuteAndCatchIfThrows_NoLock[TArg](DiagnosticAnalyzer analyzer, Action1 analyze, TArg argument, Nullable1 info) '. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#8686>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ADIEDQIGSNRZKTD6TUFUJPTQDGX4PANCNFSM4HAASQNA> .

[pranavkm]

Hi, it looks like you are posting on a closed issue/PR/commit!

We're very likely to lose track of your bug/feedback/question unless you:

1. Open a new issue
2. Explain very clearly what you need help with
3. If you think you have found a bug, include detailed repro steps so that we can investigate the problem

Thanks!

[deathcat05]

I am having an issue as well.
I have several cs projects that target netstandard2.0. But, I have a asp.net app targeting the netcoreapp3.0 which has a dependency on these 2.0 projects.

My netstandard projects reference these packages:

<PackageReference Include="Microsoft.AspNetCore.Mvc" Version="2.2.0" />
<PackageReference Include="Microsoft.Extensions.Http" Version="2.2.0" />

I don't have any need for these packages in the .csproj for my netcoreapp3.0.

[SimonCropp]

@pranavkm

Your netcoreapp3.0 application is referencing 2.2 versions of packages which is unsupported.

would it be worthwhile having some better interactive feedback as to this scenario? I assume most people will just change to <TargetFramework>netcoreapp3.0</TargetFramework> (as i did) and then cant build to a null reference in the TopLevelParameterNameAnalyzer

[DonaldAirey]

I had a working solution with no warnings or errors. Just downloaded the production release of Visual Studio 2019 16.3.0. Now I'm getting:

5>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.'.
5>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.'.
5>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.'.
5>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.'.
5>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.'.

[pranavkm]

@SimonCropp our migration guide is fairly elaborate, so hopefully this should be covered.

@gammafour \ @deathcat05 please file a separate issue, possibly with a minimal repro. I'm locking this issue since we've resolved the original issue and it's just incredibly noisy at this point.