Object reference not set error when trying to use "dotnet new bepinex5plugin" with .NET 8, works with .NET 7

[akarnokd]

Describe the bug

Having .NET 8 SDK installed on Windows 10 22H2, the following command to use a template fails with "Object reference not set to an instance of an object".

I have to install .NET 7 SDK and force 7.0.404 via global.json to make it work.

I reported the issue to the developers of the template, BepInEx/BepInEx.Templates#8, but they immediately point at .NET 8 this being a regression.

While there was no .NET 8 SDK, I was using .NET 7 on which the template worked fine before.

To Reproduce

dotnet new -i BepInEx.Templates --nuget-source https://nuget.bepinex.dev/v3/index.json

dotnet new bepinex5plugin -n MyModNameHere -T netstandard2.1 -U 2023.1.9

Exceptions (if any)

Template "BepInEx 5 Plugin Template" could not be created.
Failed to create template.
Details: Object reference not set to an instance of an object.


For details on the exit code, refer to https://aka.ms/templating-exit-codes#100

Further technical details

• Include the output of dotnet --info

.NET SDK:
 Version:           8.0.100
 Commit:            57efcf1350
 Workload version:  8.0.100-manifests.6a1e483a

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.19045
 OS Platform: Windows
 RID:         win-x64
 Base Path:   C:\Program Files\dotnet\sdk\8.0.100\

.NET workloads installed:
 Workload version: 8.0.100-manifests.6a1e483a
There are no installed workloads to display.

Host:
  Version:      8.0.0
  Architecture: x64
  Commit:       5535e31a71

.NET SDKs installed:
  7.0.404 [C:\Program Files\dotnet\sdk]
  8.0.100 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.All 2.1.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.App 2.1.0 [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 6.0.25 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 7.0.14 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 8.0.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 6.0.25 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 7.0.14 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 8.0.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 6.0.25 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 7.0.14 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 8.0.0 [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

Not applicable. Using command line.

[baronfel]

For the team, here is the detailed output from invoking the template:

% dotnet new bepinex5plugin -n MyModNameHere -T netstandard2.1 -U 2023.1.9 -v diagnostic

[2023-11-17 07:01:56.780] [Debug] [Template Engine] => [Execute]: Execute started
[2023-11-17 07:01:56.835] [Debug] [Microsoft.TemplateEngine.Edge.TemplateConstraintManager] => [Execute]: Found 5 constraints factories, initializing.
[2023-11-17 07:01:56.835] [Debug] [Microsoft.TemplateEngine.Edge.TemplateConstraintManager] => [Execute]: Found 5 constraints factories, initializing.
[2023-11-17 07:01:56.838] [Debug] [MSBuildEvaluator] => [Execute]: Output directory is: /home/chethusk/code/container-webapp.
[2023-11-17 07:01:56.838] [Debug] [MSBuildEvaluator] => [Execute]: Project full path is: <null>.
[2023-11-17 07:01:56.839] [Debug] [MSBuildEvaluator] => [Execute]: Found project files: /home/chethusk/code/container-webapp/container-webapp.csproj.
[2023-11-17 07:01:56.839] [Debug] [MSBuildEvaluator] => [Execute]: Evaluating project: /home/chethusk/code/container-webapp/container-webapp.csproj
[2023-11-17 07:01:56.857] [Debug] [Template Engine] => [Execute] => [Template from config /home/chethusk/.templateengine/packages/BepInEx.Templates.1.4.0.nupkg/content/templates/BepInEx5.PluginTemplate/.template.config/template.json]: Template from config /home/chethusk/.templateengine/packages/BepInEx.Templates.1.4.0.nupkg/content/templates/BepInEx5.PluginTemplate/.template.config/template.json started
[2023-11-17 07:01:56.881] [Debug] [Template Engine] => [Execute] => [Template from config /home/chethusk/.templateengine/packages/BepInEx.Templates.1.4.0.nupkg/content/templates/BepInEx5.PluginTemplate/.template.config/template.json]: Template from config /home/chethusk/.templateengine/packages/BepInEx.Templates.1.4.0.nupkg/content/templates/BepInEx5.PluginTemplate/.template.config/template.json finished, took 22 ms
[2023-11-17 07:01:56.881] [Debug] [Template Engine] => [Execute]: Found template 'BepInEx 5 Plugin Template' (BepInEx5.Plugin)
[2023-11-17 07:01:56.882] [Debug] [Template Engine] => [Execute]: The template 'BepInEx 5 Plugin Template' (BepInEx5.Plugin) has the following validation messages:
   [Info][MV007] Missing 'groupIdentity'.
   [Info][MV008] Missing 'generatorVersions'.
   [Info][MV009] Missing 'precedence'.

[2023-11-17 07:01:56.882] [Debug] [Microsoft.TemplateEngine.Edge.Template.TemplateCreator] => [Execute] => [Template content generation]: Template content generation started
[2023-11-17 07:01:56.889] [Debug] [NuGetLogger] => [Execute]: Searching for BepInEx.Templates in https://nuget.bepinex.dev/v3/index.json.
[2023-11-17 07:01:56.915] [Debug] [NuGetLogger] => [Execute]:   GET https://nuget.bepinex.dev/v3/registration/bepinex.templates/index.json
[2023-11-17 07:01:56.915] [Debug] [Microsoft.TemplateEngine.Edge.Template.TemplateCreator] => [Execute] => [Template content generation]: Template content generation finished, took 32 ms
Template "BepInEx 5 Plugin Template" could not be created.
Failed to create template.
Details: Object reference not set to an instance of an object.
[2023-11-17 07:01:56.938] [Debug] [NuGetLogger] => [Execute]: Searching for BepInEx.Templates in https://api.nuget.org/v3/index.json.
[2023-11-17 07:01:56.941] [Debug] [NuGetLogger] => [Execute]:   GET https://api.nuget.org/v3/registration5-gz-semver2/bepinex.templates/index.json
[2023-11-17 07:01:57.157] [Debug] [MSBuildEvaluator] => [Execute]: SDK-style project: True
[2023-11-17 07:01:57.157] [Debug] [MSBuildEvaluator] => [Execute]: Target frameworks:
[2023-11-17 07:01:57.157] [Debug] [MSBuildEvaluator] => [Execute]: Target framework: net8.0
[2023-11-17 07:01:57.157] [Debug] [MSBuildEvaluator] => [Execute]: Project is SDK style, single TFM:net8.0, evaluation succeeded.
[2023-11-17 07:01:57.400] [Debug] [NuGetLogger] => [Execute]:   NotFound https://api.nuget.org/v3/registration5-gz-semver2/bepinex.templates/index.json 458ms
[2023-11-17 07:01:57.403] [Debug] [NuGetLogger] => [Execute]: BepInEx.Templates is not found in NuGet feed https://api.nuget.org/v3/index.json.
[2023-11-17 07:01:57.554] [Debug] [NuGetLogger] => [Execute]:   OK https://nuget.bepinex.dev/v3/registration/bepinex.templates/index.json 638ms
[2023-11-17 07:01:57.586] [Debug] [NuGetLogger] => [Execute]: Found 7 versions for BepInEx.Templates in NuGet feed https://nuget.bepinex.dev/v3/index.json.
[2023-11-17 07:01:57.588] [Debug] [NuGetLogger] => [Execute]: Found 1 search endpoints.
[2023-11-17 07:01:57.588] [Debug] [NuGetLogger] => [Execute]: Querying https://nuget.bepinex.dev/v3/search?q=BepInEx.Templates&skip=0&take=1&prerelease=true&semVerLevel=2.0.0


[2023-11-17 07:01:57.793] [Debug] [Template Engine] => [Execute]: Execute finished, took 1014 ms
For details on the exit code, refer to https://aka.ms/templating-exit-codes#100

[anisghaoui]

I have got the same issue here.

[wildstingray]

Issue with 8 .net
install 6 or 7 .net to resolve 😢

[nixtap]

I have got the same issue here.

Me too. I am sure that issue is caused by .NET SDK 8.