Migrate to the Options pattern for Screenplay Options

[craigfowler]

At present, Reqnroll & SpecFlow (I might drop support for SpecFlow) use the BoDi DI container. This container does not support the .NET Options pattern, because it lacks some of the necessary features. What I would like to do is to permit the use of Configure functions from the IServiceCollection, so that Screenplay extensions may additively configure the Screenplay options, without needing to use multiple mechanisms by which to do it (the second parameter to Screenplay.Create).

Unfortunately, I must wait for the BoDi container to be replaced in Reqnroll in order to do this, so that this technique becomes available.

[craigfowler]

The CSF.Screenplay.ServiceCollectionAdapter class in the SpecFlow/Reqnroll projects is insufficient for this purpose. It cannot support the GetEnumerator method, because:

• IObjectContainer does not contain it, or functionality which could be adapted to serve in its place
• The ObjectContainer concrete type suffers the same problem

I had a try using the concrete type's _registrations private field, but the key and value types of this concurrent dictionary are private contained types which cannot be accessed from outside the object container. The .NET Options pattern requires the GetEnumerator method of the service collection, so there is no way to implement this at present.

Here's the exception I receive when I try. This when I made an experimental change (never committed) around ScreenplayServiceCollectionExtensions line 36 to use the options pattern.

Failed AddTypeShouldAddToObjectContainer [87 ms]
  Error Message:
   OneTimeSetUp: System.NotSupportedException : This method is not supported for ServiceCollectionAdapter; a BoDi object container is not a true service collection.
  Stack Trace:
     at CSF.Screenplay.ServiceCollectionAdapter.GetEnumerator() in E:\Craig\Documents\Projects\CSF.Screenplay\CSF.Screenplay.Reqnroll\ServiceCollectionAdapter.cs:line 137
   at System.Linq.Enumerable.Any[TSource](IEnumerable`1 source, Func`2 predicate)
   at Microsoft.Extensions.DependencyInjection.Extensions.ServiceCollectionDescriptorExtensions.TryAdd(IServiceCollection collection, ServiceDescriptor descriptor)
   at Microsoft.Extensions.DependencyInjection.OptionsServiceCollectionExtensions.AddOptions(IServiceCollection services)
   at Microsoft.Extensions.DependencyInjection.OptionsServiceCollectionExtensions.AddOptions[TOptions](IServiceCollection services, String name)
   at Microsoft.Extensions.DependencyInjection.OptionsServiceCollectionExtensions.AddOptions[TOptions](IServiceCollection services)
   at CSF.Screenplay.ScreenplayServiceCollectionExtensions.AddScreenplay(IServiceCollection services) in E:\Craig\Documents\Projects\CSF.Screenplay\CSF.Screenplay\ScreenplayServiceCollectionExtensions.cs:line 36
   at CSF.Screenplay.ScreenplayPlugin.OnCustomizeGlobalDependencies(Object sender, CustomizeGlobalDependenciesEventArgs args) in E:\Craig\Documents\Projects\CSF.Screenplay\CSF.Screenplay.Reqnroll\ScreenplayPlugin.cs:line 109
   at Reqnroll.Plugins.RuntimePluginEvents.RaiseCustomizeGlobalDependencies(ObjectContainer container, ReqnrollConfiguration reqnrollConfiguration)
   at Reqnroll.Infrastructure.ContainerBuilder.CreateGlobalContainer(Assembly testAssembly, IRuntimeConfigurationProvider configurationProvider)
   at Reqnroll.TestRunnerManager.CreateTestRunnerManager(Assembly testAssembly, IContainerBuilder containerBuilder)
   at Reqnroll.TestRunnerManager.<>c__DisplayClass38_0.<GetTestRunnerManager>b__0(Assembly assembly)
   at System.Collections.Concurrent.ConcurrentDictionary`2.GetOrAdd(TKey key, Func`2 valueFactory)
   at Reqnroll.TestRunnerManager.GetTestRunnerManager(Assembly testAssembly, IContainerBuilder containerBuilder, Boolean createIfMissing)
   at Reqnroll.TestRunnerManager.OnTestRunStartAsync(Assembly testAssembly, String testWorkerId, IContainerBuilder containerBuilder)
-- <further irrelevant stack frames omitted>

[craigfowler]

In fact, in the branch for #281 I might have a solution to this.

• Use MSDI libraries v6.0.0+
• Include a workaround to resolving IEnumerable<T> from the container