Fix MAUI iOS simulator launch in VS Code

extension/src/debugger/languages/dotnet.ts

@@ -8,7 +8,7 @@ import * as readline from 'readline';
 import * as os from 'os';
 import * as fs from 'fs';
 import { doesFileExist } from '../../utils/io';
-import { AspireResourceExtendedDebugConfiguration, ExecutableLaunchConfiguration, isProjectLaunchConfiguration, ProjectLaunchConfiguration } from '../../dcp/types';
+import { AspireResourceExtendedDebugConfiguration, EnvVar, ExecutableLaunchConfiguration, isProjectLaunchConfiguration, ProjectLaunchConfiguration } from '../../dcp/types';
 import { ResourceDebuggerExtension } from '../debuggerExtensions';
 import {
     readLaunchSettings,
@@ -232,8 +232,12 @@ function quoteCommandLineArgument(argument: string): string {
     return `"${argument.replace(/"/g, '\\"')}"`;
 }
 
+function createDotNetRunBaseArguments(projectPath: string): string[] {
+    return ['run', '--project', projectPath, '--no-launch-profile'];
+}
+
 function createDotNetRunArguments(projectPath: string, baseProfileArgs: string | undefined, runSessionArgs: string[] | undefined): string[] | string {
-    const dotnetRunArgs = ['run', '--project', projectPath, '--no-launch-profile'];
+    const dotnetRunArgs = createDotNetRunBaseArguments(projectPath);
     if (runSessionArgs !== undefined) {
         if (runSessionArgs.length > 0) {
             dotnetRunArgs.push('--', ...runSessionArgs);
@@ -253,6 +257,24 @@ function createDotNetRunArguments(projectPath: string, baseProfileArgs: string |
     return dotnetRunArgs;
 }
 
+function configureDotNetRunDebugConfiguration(
+    debugConfiguration: AspireResourceExtendedDebugConfiguration,
+    projectPath: string,
+    args: string[] | string,
+    baseProfileEnvironmentVariables: { [key: string]: string } | undefined,
+    runSessionEnvironmentVariables: EnvVar[]): void {
+    debugConfiguration.program = 'dotnet';
+    debugConfiguration.args = args;
+    debugConfiguration.cwd = path.dirname(projectPath);
+    debugConfiguration.executablePath = undefined;
+    debugConfiguration.noDebug = true;
+    debugConfiguration.env = Object.fromEntries(mergeEnvironmentVariables(
+        baseProfileEnvironmentVariables,
+        debugConfiguration.env,
+        runSessionEnvironmentVariables
+    ));
+}
+
 export function createProjectDebuggerExtension(dotNetServiceProducer: (debugSession: AspireDebugSession) => IDotNetService): ResourceDebuggerExtension {
     return {
         resourceType: 'project',
@@ -268,8 +290,6 @@ export function createProjectDebuggerExtension(dotNetServiceProducer: (debugSess
             throw new Error(invalidLaunchConfiguration(JSON.stringify(launchConfig)));
         },
         createDebugSessionConfigurationCallback: async (launchConfig, args, env, launchOptions, debugConfiguration: AspireResourceExtendedDebugConfiguration): Promise<void> => {
-            const dotNetService: IDotNetService = dotNetServiceProducer(launchOptions.debugSession);
-
             if (!isProjectLaunchConfiguration(launchConfig)) {
                 extensionLogOutputChannel.info(`The resource type was not project for ${JSON.stringify(launchConfig)}`);
                 throw new Error(invalidLaunchConfiguration(JSON.stringify(launchConfig)));
@@ -318,6 +338,8 @@ export function createProjectDebuggerExtension(dotNetServiceProducer: (debugSess
             }
 
             if (baseProfile?.commandName?.toLowerCase() === LaunchProfileCommandName.executable && baseProfile.executablePath) {
+                const dotNetService: IDotNetService = dotNetServiceProducer(launchOptions.debugSession);
+
                 // For Executable command profiles (e.g., class library integrations), the launch profile
                 // specifies an external executable to run instead of the project output.
                 // Build the project to ensure dependencies are compiled, then launch
@@ -340,6 +362,7 @@ export function createProjectDebuggerExtension(dotNetServiceProducer: (debugSess
                 ));
             }
             else if (!isFileBasedApp(projectPath)) {
+                const dotNetService: IDotNetService = dotNetServiceProducer(launchOptions.debugSession);
                 const outputPath = await dotNetService.getDotNetTargetPath(projectPath);
                 if ((!(await doesFileExist(outputPath)) || launchOptions.forceBuild)) {
                     await dotNetService.buildDotNetProject(projectPath);
@@ -352,21 +375,19 @@ export function createProjectDebuggerExtension(dotNetServiceProducer: (debugSess
                         vscode.window.showInformationMessage(fallbackMessage);
                     }
 
-                    debugConfiguration.program = 'dotnet';
-                    debugConfiguration.args = createDotNetRunArguments(projectPath, baseProfile?.commandLineArgs, args);
-                    debugConfiguration.cwd = path.dirname(projectPath);
-                    debugConfiguration.executablePath = undefined;
-                    debugConfiguration.noDebug = true;
+                    configureDotNetRunDebugConfiguration(debugConfiguration, projectPath, createDotNetRunArguments(projectPath, baseProfile?.commandLineArgs, args), baseProfile?.environmentVariables, env);
                 } else {
                     debugConfiguration.program = outputPath;
+                    debugConfiguration.env = Object.fromEntries(mergeEnvironmentVariables(
+                        baseProfile?.environmentVariables,
+                        debugConfiguration.env,
+                        env
+                    ));
                 }
-                debugConfiguration.env = Object.fromEntries(mergeEnvironmentVariables(
-                    baseProfile?.environmentVariables,
-                    debugConfiguration.env,
-                    env
-                ));
             }
             else {
+                const dotNetService: IDotNetService = dotNetServiceProducer(launchOptions.debugSession);
+
                 // For file-based apps, get the dotnet run-api output first to determine the executable path
                 const runApiOutput = await dotNetService.getDotNetRunApiOutput(projectPath);
                 const runApiConfig = getRunApiConfigFromOutput(runApiOutput);

extension/src/test/dotnetDebugger.test.ts

@@ -268,6 +268,34 @@ suite('Dotnet Debugger Extension Tests', () => {
         assert.strictEqual(dotNetService.buildDotNetProjectStub.notCalled, true);
     });
 
+    test('does not use dotnet run when ordinary project launch configuration requests NoDebug', async () => {
+        const outputPath = '/tmp/bin/Debug/net10.0/Worker.dll';
+        const { extension } = createDebuggerExtension(outputPath, null, true, true);
+
+        const projectPath = '/tmp/Worker.csproj';
+        const launchConfig: ProjectLaunchConfiguration = {
+            type: 'project',
+            mode: 'NoDebug',
+            project_path: projectPath
+        };
+
+        const debugConfig: AspireResourceExtendedDebugConfiguration = {
+            runId: '1',
+            debugSessionId: '1',
+            type: 'coreclr',
+            name: 'Test Debug Config',
+            request: 'launch',
+            noDebug: true
+        };
+
+        const fakeAspireDebugSession = sinon.createStubInstance(AspireDebugSession);
+
+        await extension.createDebugSessionConfigurationCallback!(launchConfig, [], [], { debug: false, runId: '1', debugSessionId: '1', isApphost: false, debugSession: fakeAspireDebugSession }, debugConfig);
+
+        assert.strictEqual(debugConfig.program, outputPath);
+        assert.strictEqual(debugConfig.noDebug, true);
+    });
+
     test('uses dotnet CLI when project runtimeconfig has no runnable framework', async () => {
         const fs = require('fs');
         const path = require('path');

src/Aspire.Hosting.Maui/MauiiOSExtensions.cs

@@ -360,14 +360,20 @@ public static IResourceBuilder<MauiiOSSimulatorResource> AddiOSSimulator(
 
         var iOSSimulatorResource = new MauiiOSSimulatorResource(name, builder.Resource);
 
+#pragma warning disable ASPIREEXTENSION001 // WithDebugSupport is experimental
         var resourceBuilder = builder.ApplicationBuilder.AddResource(iOSSimulatorResource)
             .WithAnnotation(new MauiProjectMetadata(projectPath))
             .WithAnnotation(new MauiiOSEnvironmentAnnotation()) // Enable environment variable support via targets file
             .WithAnnotation(new ExecutableAnnotation
             {
                 Command = "dotnet",
                 WorkingDirectory = workingDirectory
-            });
+            })
+            // VS Code does not advertise this launch type, so DCP runs the simulator
+            // resource as the executable below. That keeps the MAUI SDK `dotnet run`
+            // target in control instead of launching the compiled DLL directly.
+            .WithDebugSupport(_ => new { type = "maui-ios-simulator" }, "maui-ios-simulator");
+#pragma warning restore ASPIREEXTENSION001
 
         // Build additional arguments for simulator UDID if specified
         // For iOS simulators, we need to use the MSBuild property _DeviceName with the :v2:udid= prefix