Is there a warnings-by-level list anywhere?

[SRNissen]

I have a project with a CS8618 warning shown by my IDE (JetBrains Rider).

The warning is correct (that is, the field is not initialized before leaving the ctor)

The .csproj has:

<PropertyGroup Condition=" '$(Configuration)' == 'Debug' ">
    <AnalysisLevel>latest</AnalysisLevel>
    <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
</PropertyGroup>

<PropertyGroup Condition=" '$(Configuration)' == 'Release' ">
    <AnalysisLevel>latest</AnalysisLevel>
    <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
</PropertyGroup>

I have tried with any combination of Warning and Analysis level but I cannot make the project stop building.

I've been looking through a lot of documentation over the last few hours and I simply cannot find a list of warnings-by-warning-level that'll tell me how my Rider setup is different from my project and, in particular, what to do to make this project stop building on this and similar errors.

[huoyaoyuan]

https://learn.microsoft.com/dotnet/csharp/language-reference/compiler-messages/warning-waves

CS8618 is a nullable warning. Do you have <Nullable>enable</Nullable> in your project? Is there warning reported when doing command line build?

[SRNissen]

Sure - I have a public repo that demos the issue

$ gh repo clone SRNissen/demos

Cloning into 'demos'...
remote: Enumerating objects: 20, done.
remote: Counting objects: 100% (20/20), done.
remote: Compressing objects: 100% (15/15), done.
remote: Total 20 (delta 5), reused 19 (delta 4), pack-reused 0
Receiving objects: 100% (20/20), 6.17 KiB | 6.17 MiB/s, done.
Resolving deltas: 100% (5/5), done.

$ cd demos/warninglist

$ dotnet build

MSBuild version 17.8.3+195e7f5a3 for .NET
  Determining projects to restore...
  All projects are up-to-date for restore.
  warninglist -> /home/srnissen/repos/srnissen/demos/warninglist/bin/Debug/net8.0/warninglist.dll

Build succeeded.
    0 Warning(s)
    0 Error(s)

Time Elapsed 00:00:01.06

• To be clear: With this question,
  • I am not looking for:
    • Changes to this project.
  • I am looking for:
    • C# documentation of all warnings, and the flags necessary to enable/disable them.

[huoyaoyuan]

Most warnings don't belong to a warning wave. They just belong to the language version they were introduced in. Most nullable warnings belong to C# 8. Only warning for previously legal code would be included in a warning wave, to avoid sudden change for compiler version upgrade.

Look at the source code about warning level:

roslyn/src/Compilers/CSharp/Portable/Errors/ErrorFacts.cs

Lines 206 to 241 in 983d20f

	// Warning wave warnings (warning level > 4) should be documented in
	// docs/compilers/CSharp/Warnversion Warning Waves.md
	switch (code)
	{
	case ErrorCode.WRN_AddressOfInAsync:
	case ErrorCode.WRN_ByValArraySizeConstRequired:
	// Warning level 8 is exclusively for warnings introduced in the compiler
	// shipped with dotnet 8 (C# 12) and that can be reported for pre-existing code.
	return 8;
	case ErrorCode.WRN_LowerCaseTypeName:
	// Warning level 7 is exclusively for warnings introduced in the compiler
	// shipped with dotnet 7 (C# 11) and that can be reported for pre-existing code.
	return 7;
	case ErrorCode.WRN_PartialMethodTypeDifference:
	// Warning level 6 is exclusively for warnings introduced in the compiler
	// shipped with dotnet 6 (C# 10) and that can be reported for pre-existing code.
	return 6;
	case ErrorCode.WRN_NubExprIsConstBool2:
	case ErrorCode.WRN_StaticInAsOrIs:
	case ErrorCode.WRN_PrecedenceInversion:
	case ErrorCode.WRN_UseDefViolationPropertyUnsupportedVersion:
	case ErrorCode.WRN_UseDefViolationFieldUnsupportedVersion:
	case ErrorCode.WRN_UnassignedThisAutoPropertyUnsupportedVersion:
	case ErrorCode.WRN_UnassignedThisUnsupportedVersion:
	case ErrorCode.WRN_ParamUnassigned:
	case ErrorCode.WRN_UseDefViolationProperty:
	case ErrorCode.WRN_UseDefViolationField:
	case ErrorCode.WRN_UseDefViolationThisUnsupportedVersion:
	case ErrorCode.WRN_UseDefViolationOut:
	case ErrorCode.WRN_UseDefViolation:
	case ErrorCode.WRN_SyncAndAsyncEntryPoints:
	case ErrorCode.WRN_ParameterIsStaticClass:
	case ErrorCode.WRN_ReturnTypeIsStaticClass:
	// Warning level 5 is exclusively for warnings introduced in the compiler
	// shipped with dotnet 5 (C# 9) and that can be reported for pre-existing code.
	return 5;

So this page is already exhaustive for warning waves.

[huoyaoyuan]

The reason you are not seeing the warning is because it's suppressed by NUnit.Analyzers: https://github.com/nunit/nunit.analyzers/blob/master/src/nunit.analyzers/DiagnosticSuppressors/NonNullableFieldOrPropertyIsUninitializedSuppressor.cs

So it is in fact a Rider issue that not handling the suppressor.

[SRNissen]

So this page is already exhaustive for warning waves.

It is not.

For example, try finding the exact warning that instigated this thread, CS8618.

[huoyaoyuan]

Most warnings aren't controlled by any options or warning waves. CS8618 isn't in the page because it isn't in any warning level, or effectively level 0. They are just enabled unconditionally with the proper language feature. The linked ErrorFacts source code is source-of-truth.