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Object reference not set to an instance of an object

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
25/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale
Tech stack
csharp
Domain
tooling

Research direction

Reproduce the provided Cake script and inspect the stack from Cake.Graph.Templates.GraphTemplateManager through RazorLight. Start at RazorLight.Compilation.DefaultMetadataReferenceManager.Resolve and the graph template parsing path; done means Mermaid HTML graph generation completes without the NullReferenceException.

Written by the indexing model from the issue text.

Description

Hi!
Trying to generate tasks dependency graph and getting "Object reference not set to an instance of an object" error.

#addin nuget:?package=System.Collections.Immutable&version=1.2.0
#addin nuget:?package=Cake.Graph&prerelease&loaddependencies=true&version=0.8.0

Task("Graph")
    .Does(() => {
        Graph(Tasks).Deploy(s => s          
          .WithMermaidHtmlGenerator()
          .SetOutputPath("docs")
        );
    });

Running cake build with diagnostic logging gives me the following stack trace:

An error occurred when executing task 'Graph'.
Executing custom task teardown action (Graph)...
##teamcity[blockClosed name='Graph']
Error: System.AggregateException: One or more errors occurred. ---> System.NullReferenceException: Object reference not set to an instance of an object.
   at RazorLight.Compilation.DefaultMetadataReferenceManager.Resolve(DependencyContext dependencyContext)
   at RazorLight.Compilation.RoslynCompilationService.EnsureOptions()
   at RazorLight.Compilation.RoslynCompilationService.get_ParseOptions()
   at RazorLight.Compilation.RoslynCompilationService.CreateSyntaxTree(SourceText sourceText)
   at RazorLight.Compilation.RoslynCompilationService.CreateCompilation(String compilationContent, String assemblyName)
   at RazorLight.Compilation.RoslynCompilationService.CompileAndEmit(IGeneratedRazorTemplate razorTemplate)
   at RazorLight.Compilation.RoslynCompilationService.CompileAsync(IGeneratedRazorTemplate razorTemplate)
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at RazorLight.Compilation.TemplateFactoryProvider.<CompileAsync>d__10.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at RazorLight.Compilation.TemplateFactoryProvider.<CreateFactoryAsync>d__8.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at RazorLight.RazorLightEngine.<CompileTemplateAsync>d__14.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at RazorLight.RazorLightEngine.<CompileRenderAsync>d__11.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Graph.Templates.GraphTemplateManager.<ParseAndCacheRazorTemplateAsync>d__8`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Graph.Templates.GraphTemplateManager.<ParseRazorTemplateFromResourceAsync>d__7`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Graph.Templates.GraphTemplateManager.<ParseTemplateAsync>d__6`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Graph.Generators.MermaidHtmlGenerator.<SerializeAsync>d__8.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Graph.GraphRunner.<DeployAsync>d__5.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Graph.GraphRunner.<DeployAsync>d__3.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Graph.GraphRunner.Deploy(Action`1 configure)
   at Submission#0.<<Initialize>>b__0_20()
   at Cake.Core.CakeTaskBuilderExtensions.<>c__DisplayClass24_0.<Does>b__0(ICakeContext x)
   at Cake.Core.CakeTask.<Execute>d__43.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Core.DefaultExecutionStrategy.<ExecuteAsync>d__4.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Core.CakeEngine.<ExecuteTaskAsync>d__31.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Core.CakeEngine.<RunTask>d__28.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Core.CakeEngine.<RunTargetAsync>d__27.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Scripting.BuildScriptHost.<RunTargetAsync>d__3.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Core.Scripting.ScriptHost.RunTarget(String target)
   at Submission#0.<<Initialize>>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.CodeAnalysis.Scripting.ScriptExecutionState.<RunSubmissionsAsync>d__9`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.CodeAnalysis.Scripting.Script`1.<RunSubmissionsAsync>d__21.MoveNext()
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
   at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
   at Cake.Scripting.Roslyn.RoslynScriptSession.Execute(Script script)
   at Cake.Core.Scripting.ScriptRunner.Run(IScriptHost host, FilePath scriptPath, IDictionary`2 arguments)
   at Cake.Commands.BuildCommand.Execute(CakeOptions options)
   at Cake.CakeApplication.Run(CakeOptions options)
   at Cake.Program.Main()
---> (Inner Exception #0) System.NullReferenceException: Object reference not set to an instance of an object.
   at RazorLight.Compilation.DefaultMetadataReferenceManager.Resolve(DependencyContext dependencyContext)
   at RazorLight.Compilation.RoslynCompilationService.EnsureOptions()
   at RazorLight.Compilation.RoslynCompilationService.get_ParseOptions()
   at RazorLight.Compilation.RoslynCompilationService.CreateSyntaxTree(SourceText sourceText)
   at RazorLight.Compilation.RoslynCompilationService.CreateCompilation(String compilationContent, String assemblyName)
   at RazorLight.Compilation.RoslynCompilationService.CompileAndEmit(IGeneratedRazorTemplate razorTemplate)
   at RazorLight.Compilation.RoslynCompilationService.CompileAsync(IGeneratedRazorTemplate razorTemplate)
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at RazorLight.Compilation.TemplateFactoryProvider.<CompileAsync>d__10.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at RazorLight.Compilation.TemplateFactoryProvider.<CreateFactoryAsync>d__8.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at RazorLight.RazorLightEngine.<CompileTemplateAsync>d__14.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at RazorLight.RazorLightEngine.<CompileRenderAsync>d__11.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Graph.Templates.GraphTemplateManager.<ParseAndCacheRazorTemplateAsync>d__8`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Graph.Templates.GraphTemplateManager.<ParseRazorTemplateFromResourceAsync>d__7`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Graph.Templates.GraphTemplateManager.<ParseTemplateAsync>d__6`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Graph.Generators.MermaidHtmlGenerator.<SerializeAsync>d__8.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Graph.GraphRunner.<DeployAsync>d__5.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Graph.GraphRunner.<DeployAsync>d__3.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Graph.GraphRunner.Deploy(Action`1 configure)
   at Submission#0.<<Initialize>>b__0_20()
   at Cake.Core.CakeTaskBuilderExtensions.<>c__DisplayClass24_0.<Does>b__0(ICakeContext x)
   at Cake.Core.CakeTask.<Execute>d__43.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Core.DefaultExecutionStrategy.<ExecuteAsync>d__4.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Core.CakeEngine.<ExecuteTaskAsync>d__31.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Core.CakeEngine.<RunTask>d__28.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Core.CakeEngine.<RunTargetAsync>d__27.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Scripting.BuildScriptHost.<RunTargetAsync>d__3.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cake.Core.Scripting.ScriptHost.RunTarget(String target)
   at Submission#0.<<Initialize>>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.CodeAnalysis.Scripting.ScriptExecutionState.<RunSubmissionsAsync>d__9`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.CodeAnalysis.Scripting.Script`1.<RunSubmissionsAsync>d__21.MoveNext()<---

When I use non-html generators everything works and I get .md or .json files.
What could be the source of this problem?

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