[release/9.1] Fix arg annotations when running in IDE mode (#7722)

* Fix arg annotations when running in IDE mode

* Comment

* Comment

* Comments and refactor

---------

Co-authored-by: James Newton-King <[email protected]>

Author: github-actions[bot]

src/Aspire.Hosting/Dcp/DcpExecutor.cs

@@ -966,31 +966,31 @@ private async Task CreateExecutableAsync(AppResource er, ILogger resourceLogger,
         }
         var spec = exe.Spec;
 
+        // Don't create an args collection unless needed. A null args collection means a project run by the will use args provided by the launch profile.
+        // https://github.com/dotnet/aspire/blob/main/docs/specs/IDE-execution.md#launch-profile-processing-project-launch-configuration
+        spec.Args = null;
+
         // An executable can be restarted so args must be reset to an empty state.
         // After resetting, first apply any dotnet project related args, e.g. configuration, and then add args from the model resource.
-        spec.Args = [];
-        if (er.DcpResource.TryGetAnnotationAsObjectList<string>(CustomResource.ResourceProjectArgsAnnotation, out var projectArgs))
+        if (er.DcpResource.TryGetAnnotationAsObjectList<string>(CustomResource.ResourceProjectArgsAnnotation, out var projectArgs) && projectArgs.Count > 0)
         {
+            spec.Args ??= [];
             spec.Args.AddRange(projectArgs);
         }
 
-        var launchArgs = new List<(string Value, bool IsSensitive, bool AnnotationOnly)>();
+        // Get args from app host model resource.
+        (var appHostArgs, var failedToApplyArgs) = await BuildArgsAsync(resourceLogger, er.ModelResource, cancellationToken).ConfigureAwait(false);
 
-        // If the executable is a project then include any command line args from the launch profile.
-        if (er.ModelResource is ProjectResource project)
-        {
-            // When the .NET project is launched from an IDE the launch profile args are automatically added.
-            // We still want to display the args in the dashboard so only add them to the custom arg annotations.
-            var annotationOnly = spec.ExecutionType == ExecutionType.IDE;
+        var launchArgs = BuildLaunchArgs(er, spec, appHostArgs);
 
-            var launchProfileArgs = GetLaunchProfileArgs(project.GetEffectiveLaunchProfile()?.LaunchProfile);
-            launchArgs.AddRange(launchProfileArgs.Select(a => (a, isSensitive: false, annotationOnly)));
+        var executableArgs = launchArgs.Where(a => !a.AnnotationOnly).Select(a => a.Value).ToList();
+        if (executableArgs.Count > 0)
+        {
+            spec.Args ??= [];
+            spec.Args.AddRange(executableArgs);
         }
 
-        (var args, var failedToApplyArgs) = await BuildArgsAsync(resourceLogger, er.ModelResource, cancellationToken).ConfigureAwait(false);
-        launchArgs.AddRange(args.Select(a => (a.Value, a.IsSensitive, annotationOnly: false)));
-
-        spec.Args.AddRange(launchArgs.Where(a => !a.AnnotationOnly).Select(a => a.Value));
+        // Arg annotations are what is displayed in the dashboard.
         er.DcpResource.SetAnnotationAsObjectList(CustomResource.ResourceAppArgsAnnotation, launchArgs.Select(a => new AppLaunchArgumentAnnotation(a.Value, isSensitive: a.IsSensitive)));
 
         (spec.Env, var failedToApplyConfiguration) = await BuildEnvVarsAsync(resourceLogger, er.ModelResource, cancellationToken).ConfigureAwait(false);
@@ -1003,6 +1003,37 @@ private async Task CreateExecutableAsync(AppResource er, ILogger resourceLogger,
         await _kubernetesService.CreateAsync(exe, cancellationToken).ConfigureAwait(false);
     }
 
+    private static List<(string Value, bool IsSensitive, bool AnnotationOnly)> BuildLaunchArgs(AppResource er, ExecutableSpec spec, List<(string Value, bool IsSensitive)> appHostArgs)
+    {
+        // Launch args is the final list of args that are displayed in the UI and possibly added to the executable spec.
+        // They're built from app host resource model args and any args in the effective launch profile.
+        // Follows behavior in the IDE execution spec when in IDE execution mode:
+        // https://github.com/dotnet/aspire/blob/main/docs/specs/IDE-execution.md#launch-profile-processing-project-launch-configuration
+        var launchArgs = new List<(string Value, bool IsSensitive, bool AnnotationOnly)>();
+
+        // If the executable is a project then include any command line args from the launch profile.
+        if (er.ModelResource is ProjectResource project)
+        {
+            // Args in the launch profile is used when:
+            // 1. The project is run as an executable. Launch profile args are combined with app host supplied args.
+            // 2. The project is run by the IDE and no app host args are specified.
+            if (spec.ExecutionType == ExecutionType.Process || (spec.ExecutionType == ExecutionType.IDE && appHostArgs.Count == 0))
+            {
+                // When the .NET project is launched from an IDE the launch profile args are automatically added.
+                // We still want to display the args in the dashboard so only add them to the custom arg annotations.
+                var annotationOnly = spec.ExecutionType == ExecutionType.IDE;
+
+                var launchProfileArgs = GetLaunchProfileArgs(project.GetEffectiveLaunchProfile()?.LaunchProfile);
+                launchArgs.AddRange(launchProfileArgs.Select(a => (a, isSensitive: false, annotationOnly)));
+            }
+        }
+
+        // In the situation where args are combined (process execution) the app host args are added after the launch profile args.
+        launchArgs.AddRange(appHostArgs.Select(a => (a.Value, a.IsSensitive, annotationOnly: false)));
+
+        return launchArgs;
+    }
+
     private static List<string> GetLaunchProfileArgs(LaunchProfile? launchProfile)
     {
         var args = new List<string>();

tests/Aspire.Hosting.Tests/Dcp/DcpExecutorTests.cs

@@ -106,17 +106,19 @@ public async Task ResourceStarted_ProjectHasReplicas_EventRaisedOnce()
     }
 
     [Theory]
-    [InlineData(true)]
-    [InlineData(false)]
-    public async Task CreateExecutable_LaunchProfileHasCommandLineArgs_AnnotationsAdded(bool isIDE)
+    [InlineData(ExecutionType.IDE, false, null, new string[] { "--", "--test1", "--test2" })]
+    [InlineData(ExecutionType.IDE, true, new string[] { "--withargs-test" }, new string[] { "--withargs-test" })]
+    [InlineData(ExecutionType.Process, false, new string[] { "--", "--test1", "--test2" }, new string[] { "--", "--test1", "--test2" })]
+    [InlineData(ExecutionType.Process, true, new string[] { "--", "--test1", "--test2", "--withargs-test" }, new string[] { "--", "--test1", "--test2", "--withargs-test" })]
+    public async Task CreateExecutable_LaunchProfileHasCommandLineArgs_AnnotationsAdded(string executionType, bool addAppHostArgs, string[]? expectedArgs, string[]? expectedAnnotations)
     {
         var builder = DistributedApplication.CreateBuilder(new DistributedApplicationOptions
         {
             AssemblyName = typeof(DistributedApplicationTests).Assembly.FullName
         });
 
         IConfiguration? configuration = null;
-        if (isIDE)
+        if (executionType == ExecutionType.IDE)
         {
             var configurationBuilder = new ConfigurationBuilder();
             configurationBuilder.AddInMemoryCollection(new Dictionary<string, string?>
@@ -127,11 +129,15 @@ public async Task CreateExecutable_LaunchProfileHasCommandLineArgs_AnnotationsAd
             configuration = configurationBuilder.Build();
         }
 
-        var resource = builder.AddProject<Projects.ServiceA>("ServiceA")
-            .WithArgs(c =>
-            {
-                c.Args.Add("--withargs-test");
-            }).Resource;
+        var resourceBuilder = builder.AddProject<Projects.ServiceA>("ServiceA");
+        if (addAppHostArgs)
+        {
+            resourceBuilder
+                .WithArgs(c =>
+                {
+                    c.Args.Add("--withargs-test");
+                });
+        }
 
         var kubernetesService = new TestKubernetesService();
         using var app = builder.Build();
@@ -148,30 +154,12 @@ public async Task CreateExecutable_LaunchProfileHasCommandLineArgs_AnnotationsAd
 
         var exe = Assert.Single(executables);
 
-        if (isIDE)
-        {
-            var callArg = Assert.Single(exe.Spec.Args!);
-            Assert.Equal("--withargs-test", callArg);
-        }
-        else
-        {
-            // ignore dotnet specific args for .NET project
-            var callArgs = exe.Spec.Args![^4..];
-
-            Assert.Collection(callArgs,
-                a => Assert.Equal("--", a),
-                a => Assert.Equal("--test1", a),
-                a => Assert.Equal("--test2", a),
-                a => Assert.Equal("--withargs-test", a));
-        }
+        // Ignore dotnet specific args for .NET project in process execution.
+        var callArgs = executionType == ExecutionType.IDE ? exe.Spec.Args : exe.Spec.Args![^(expectedArgs?.Length ?? 0)..];
+        Assert.Equal(expectedArgs, callArgs);
 
         Assert.True(exe.TryGetAnnotationAsObjectList<AppLaunchArgumentAnnotation>(CustomResource.ResourceAppArgsAnnotation, out var argAnnotations));
-
-        Assert.Collection(argAnnotations,
-            a => Assert.Equal("--", a.Argument),
-            a => Assert.Equal("--test1", a.Argument),
-            a => Assert.Equal("--test2", a.Argument),
-            a => Assert.Equal("--withargs-test", a.Argument));
+        Assert.Equal(expectedAnnotations, argAnnotations.Select(a => a.Argument));
     }
 
     [Fact]