Is there a way to invoke InstallTool depending on the targets that will be run?

[paulomorgado]

Some builds require some expensive to acquire tools only for some targets.

It would be nice to have a way to filter that.

[nils-a]

While there is no built-in feature for it, it can be done.

Depending on the complexity of things, the "easy" way would be to try to split your script into multiple files, each file requiring only the tools needed for the tasks in that file. The "main" script file would then call the specific other files using CakeExecuteScript.

Alternatively, it is also possible to add tools fully dynamically:

The idea here is, essentially, not to directly add the #tool directive to your script, but to create temporary file on-the-fly that contains that directive and then run that file also on-the-fly using CakeExecuteScript.
This will neatly add the tool into the tools folder for later use.

Cake.Recipe does exactly this in RequireToolNotRegistered / RequireTool: https://github.com/cake-contrib/Cake.Recipe/blob/6bee4e5cfbc2ad0a89483d360864da85c7d0bd71/Source/Cake.Recipe/Content/tools.cake

[paulomorgado]

Can the same be done for CakeFrosting?

[nils-a]

Hm. Not sure.
@pascalberger, any ideas?

[pascalberger]

In Cake Frosting the IToolInstaller service can be used in a task:

[TaskName("MyTask")]
public sealed class MyTask : FrostingTask<BuildContext>
{
    private readonly IServiceProvider _provider;

    public MyTask(IServiceProvider provider)
    {
        _provider = provider;
    }

    public override void Run(BuildContext context)
    {
        var toolInstaller = (IToolInstaller)provider.GetService(typeof(IToolInstaller));
        toolInstaller.Install(new PackageReference("nuget:?package=MyPackage&version=1.0.0"));
    }
}