There doesn't seem to be a way to execute tasks or targets for 'dotnet run'

[rolfbjarne]

Description

For mobile platforms (iOS, tvOS), we need to execute tasks to figure out a few things before we can run an app.

So we implemented a target to run before the Run target:

https:/xamarin/xamarin-macios/blob/6ce5f80cb7ef96000652fdd534c9176b793402e9/dotnet/targets/Xamarin.Shared.Sdk.targets#L859

This works fine for dotnet build -t:Run, but it doesn't not work for dotnet run, because from what I can see dotnet run will pick out the RunCommand and RunArguments properties once the project has been evaluated:

sdk/src/Cli/dotnet/commands/dotnet-run/RunCommand.cs

Lines 236 to 263 in a30e465

	var project = new ProjectInstance(Project, globalProperties, null);
	string runProgram = project.GetPropertyValue("RunCommand");
	if (string.IsNullOrEmpty(runProgram))
	{
	ThrowUnableToRunError(project);
	}
	string runArguments = project.GetPropertyValue("RunArguments");
	string runWorkingDirectory = project.GetPropertyValue("RunWorkingDirectory");
	if (Args.Any())
	{
	runArguments += " " + ArgumentEscaper.EscapeAndConcatenateArgArrayForProcessStart(Args);
	}
	CommandSpec commandSpec = new CommandSpec(runProgram, runArguments);
	var command = CommandFactoryUsingResolver.Create(commandSpec)
	.WorkingDirectory(runWorkingDirectory);
	var rootVariableName = Environment.Is64BitProcess ? "DOTNET_ROOT" : "DOTNET_ROOT(x86)";
	if (Environment.GetEnvironmentVariable(rootVariableName) == null)
	{
	command.EnvironmentVariable(rootVariableName, Path.GetDirectoryName(new Muxer().MuxerPath));
	}
	return command;

instead of executing the Run target, which means that the RunCommand and RunArguments properties aren't set, because we set them inside a target:

https:/xamarin/xamarin-macios/blob/6ce5f80cb7ef96000652fdd534c9176b793402e9/dotnet/targets/Xamarin.Shared.Sdk.targets#L846-L849

The end result is that with an iOS app executing dotnet run just doesn't work:

• Install .NET 6 Preview 6 on a Mac.
• Install the iOS workload: sudo dotnet workload install microsoft-ios-sdk-full
• Clone https:/dotnet/maui-samples (hash: bb264d046139f6635ed066157c44b99010b8d1dd)
• Build & run HelloiOS

$ cd HelloiOS
$ dotnet build
$ dotnet run --no-build
A fatal error was encountered. The library 'libhostpolicy.dylib' required to execute the application was not found in '/Users/rolf/work/net6-mobile-samples/HelloiOS/bin/Debug/net6.0-ios/iossimulator-x64/'.
Failed to run as a self-contained app.
  - The application was run as a self-contained app because '/Users/rolf/work/net6-mobile-samples/HelloiOS/bin/Debug/net6.0-ios/iossimulator-x64/HelloiOS.runtimeconfig.json' did not specify a framework.
  - If this should be a framework-dependent app, specify the appropriate framework in '/Users/rolf/work/net6-mobile-samples/HelloiOS/bin/Debug/net6.0-ios/iossimulator-x64/HelloiOS.runtimeconfig.json'

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[marcpopMSFT]

This is a reasonable request but deferring to investigations around multi-project startup. @KathleenDollard

[rolfbjarne]

Any updates on this?

[baronfel]

Going to close this one as a duplicate of #31253, even though this one is older, since #31253 has more discussion on it.