CommandRuntimeException: Could not resolve type SomeCommand

[sandrock]

Hi. I'm coding a command that plays with git and local files. It works well. Then I wanted to add unit tests.

I chose to create an interface to represent git and filesystem actions so that I can mock them. I added constructor to my command:

public class FixEol : Command<FixEol.Settings>
{
    private readonly IFixEolProvider provider;

    public FixEol() { // for main runtime
        this.provider = new FixEolProvider();
    }

    public FixEol(IFixEolProvider provider) { // for unit tests
        this.provider = provider;
    }

    // more code here
}

static class Program
{
    static int Main(string[] args)
    {
        var app = new CommandApp();
        app.Configure(x =>
        {
            x.PropagateExceptions();
            x.AddCommand<FixEol>("fixeol");
        });
        return app.Run(args);
    }
}

And now this exception occurs:

Unhandled exception. Spectre.Console.Cli.CommandRuntimeException: Could not resolve type 'GitExtras.FixEol'.
---> System.InvalidOperationException: Could not find registration for 'GitExtras.IFixEolProvider'.
at Spectre.Console.Cli.ReflectionActivator.Activate(DefaultTypeResolver container) in //src/Spectre.Console.Cli/Internal/Composition/Activators.cs:line 87
at Spectre.Console.Cli.DefaultTypeResolver.Resolve(Type type) in //src/Spectre.Console.Cli/Internal/Composition/DefaultTypeResolver.cs:line 24
at Spectre.Console.Cli.TypeResolverAdapter.Resolve(Type type) in //src/Spectre.Console.Cli/Internal/TypeResolverAdapter.cs:line 21
--- End of inner exception stack trace ---
at Spectre.Console.Cli.TypeResolverAdapter.Resolve(Type type) in //src/Spectre.Console.Cli/Internal/TypeResolverAdapter.cs:line 36
at Spectre.Console.Cli.CommandTree.CreateCommand(ITypeResolver resolver) in //src/Spectre.Console.Cli/Internal/Parsing/CommandTree.cs:line 27
at Spectre.Console.Cli.CommandExecutor.Execute(CommandTree leaf, CommandTree tree, CommandContext context, ITypeResolver resolver, IConfiguration configuration) in //src/Spectre.Console.Cli/Internal/CommandExecutor.cs:line 136
at Spectre.Console.Cli.CommandExecutor.Execute(IConfiguration configuration, IEnumerable1 args) in /_/src/Spectre.Console.Cli/Internal/CommandExecutor.cs:line 85 at Spectre.Console.Cli.CommandApp.RunAsync(IEnumerable1 args) in //src/Spectre.Console.Cli/CommandApp.cs:line 84
at Spectre.Console.Cli.CommandApp.Run(IEnumerable`1 args) in //src/Spectre.Console.Cli/CommandApp.cs:line 58
at GitExtras.Program.Main(String[] args) in /home/sandrock/dev/tools-alt/src/GitExtras/Program.cs:line 19

Is there a way to annotate the injection constructor? Or to configure instantiation with a lambda?

[sandrock]

I found a workaround but I would like a proper answer.

The workaround is to use a static method and a private constructor.

    public FixEol()
    {
        this.provider = new FixEolProvider();
    }

    private FixEol(IFixEolProvider provider)
    {
        this.provider = provider;
    }

    public static FixEol Create(IFixEolProvider provider)
    {
        return new FixEol(provider);
    }

[phil-scott-78]

Multiple public constructors aren't supported. You'd either want to set up proper DI for the app, a single constructor that has defaults or maybe mark the one for testing as internal.