AddAndroidEmulator() / AddAndroidDevice() fails with "Error: Unexpected argument(s): run" — duplicate `run` in generated dotnet command

[phillipmario]

Description

Was playing around with the Maui Aspire integration, and started getting some errors. copilot did some troubleshooting, and well, when using AddAndroidEmulator() or AddAndroidDevice() in an Aspire AppHost, the Android resource immediately fails to start with:

Error: Unexpected argument(s): run
Try 'Microsoft.Android.Run --help' for more information.

The generated command passed to DCP contains a duplicate run:

dotnet run --project /path/to/App.csproj --configuration Debug --no-launch-profile run -f net10.0-android -p:AdbTarget=-e ...

iOS equivalents (AddiOSSimulator, AddMacCatalystDevice) are unaffected. I assume Apple tooling silently ignores unrecognised trailing arguments. Android's Microsoft.Android.Run enforces strict argument parsing and hard fails.

Root Cause

MauiPlatformHelper.ConfigurePlatformResource is constrained where T : ProjectResource. Because the resource is always a ProjectResource, DCP's PrepareProjectExecutables unconditionally prepends:

projectArgs.Add("run");
projectArgs.Add("--project");
projectArgs.Add(projectMetadata.ProjectPath);
projectArgs.Add("--no-launch-profile");

ConfigurePlatformResource then also appends run in its WithArgs callback:

resourceBuilder.WithArgs(context =>
{
    context.Args.Add("run");   // ← redundant: DCP already added this for all ProjectResource types
    context.Args.Add("-f");
    context.Args.Add(platformTfm);
    ...
});

Fix: remove context.Args.Add("run") from ConfigurePlatformResource's WithArgs callback. DCP handles it for all ProjectResource types. The -f <tfm> and remaining platform args should follow DCP's prefix directly.

Steps to Reproduce

var app = builder.AddMauiProject("my-app", "../MyApp/MyApp.csproj");
app.AddAndroidEmulator().WithReference(someService);

Launch the AppHost and attempt to start the Android resource.

Expected Behaviour

dotnet run --project /path/to/App.csproj --configuration Debug --no-launch-profile -f net10.0-android -p:AdbTarget=-e ...

Actual Behaviour

dotnet run --project /path/to/App.csproj --configuration Debug --no-launch-profile run -f net10.0-android -p:AdbTarget=-e ...

Versions Affected

Aspire.Hosting.Maui 13.1.1 and 13.1.2 — MauiPlatformHelper.cs is identical in both versions.

Workaround

Until fixed, i guess we can strip the duplicate in their AppHost, it seems to be working with this workaround:

app.AddAndroidEmulator()
   .WithReference(someService)
   .WithArgs(ctx => ctx.Args.Remove("run"));