Fix --watch hangs. (#8585)

* Fix --watch hangs.

* Don't prebuild in watch mode.

* Fix up merge.

Author: mitchdenny

src/Aspire.Cli/Commands/RunCommand.cs

@@ -76,27 +76,30 @@ protected override async Task<int> ExecuteAsync(ParseResult parseResult, Cancell
 
             appHostCompatabilityCheck = await AppHostHelper.CheckAppHostCompatabilityAsync(_runner, effectiveAppHostProjectFile, cancellationToken);
 
-            if (!appHostCompatabilityCheck?.IsCompatableAppHost ?? throw new InvalidOperationException("IsCompatableAppHost is null"))
+            if (!appHostCompatabilityCheck?.IsCompatableAppHost ?? throw new InvalidOperationException("IsCompatibleAppHost is null"))
             {
                 return ExitCodeConstants.FailedToDotnetRunAppHost;
             }
 
             var watch = parseResult.GetValue<bool>("--watch");
 
-            var buildExitCode = await AppHostHelper.BuildAppHostAsync(_runner, effectiveAppHostProjectFile, cancellationToken);
-
-            if (buildExitCode != 0)
+            if (!watch)
             {
-                AnsiConsole.MarkupLine($"[red bold]:thumbs_down: The project could not be built. For more information run with --debug switch.[/]");
-                return ExitCodeConstants.FailedToBuildArtifacts;
+                var buildExitCode = await AppHostHelper.BuildAppHostAsync(_runner, effectiveAppHostProjectFile, cancellationToken);
+
+                if (buildExitCode != 0)
+                {
+                    AnsiConsole.MarkupLine($"[red bold]:thumbs_down: The project could not be built. For more information run with --debug switch.[/]");
+                    return ExitCodeConstants.FailedToBuildArtifacts;
+                }
             }
 
             var backchannelCompletitionSource = new TaskCompletionSource<AppHostBackchannel>();
 
             var pendingRun = _runner.RunAsync(
                 effectiveAppHostProjectFile,
                 watch,
-                true,
+                !watch,
                 Array.Empty<string>(),
                 env,
                 backchannelCompletitionSource,

src/Aspire.Cli/Utils/AppHostHelper.cs

@@ -11,7 +11,7 @@ internal static class AppHostHelper
 {
     private static readonly ActivitySource s_activitySource = new ActivitySource(nameof(AppHostHelper));
 
-    internal static async Task<(bool IsCompatableAppHost, bool SupportsBackchannel, string? AspireHostingSdkVersion)> CheckAppHostCompatabilityAsync(DotNetCliRunner runner, FileInfo projectFile, CancellationToken cancellationToken)
+    internal static async Task<(bool IsCompatibleAppHost, bool SupportsBackchannel, string? AspireHostingSdkVersion)> CheckAppHostCompatabilityAsync(DotNetCliRunner runner, FileInfo projectFile, CancellationToken cancellationToken)
     {
             var appHostInformation = await GetAppHostInformationAsync(runner, projectFile, cancellationToken);