[browser] Library mode without workload (#122607)

Co-authored-by: Copilot <198982749+Copilot@users.noreply.github.com>
Co-authored-by: Larry Ewing <lewing@microsoft.com>

Author: 3 people

src/mono/browser/build/BrowserWasmApp.targets

@@ -50,15 +50,6 @@
     <ProjectCapability Include="DotNetCoreWeb"/>
   </ItemGroup>
 
-  <!-- When trimming non-exe projects, root the whole intermediate assembly. -->
-  <Target Name="_RootEntireIntermediateAssembly" AfterTargets="PrepareForILLink" BeforeTargets="_RunILLink" Condition="'$(RuntimeIdentifier)' == 'browser-wasm' And '$(OutputType)' == 'Library'">
-    <ItemGroup>
-      <TrimmerRootAssembly Condition="'%(Identity)' == '$(AssemblyName)'">
-        <RootMode>all</RootMode>
-      </TrimmerRootAssembly>
-    </ItemGroup>
-  </Target>
-
   <Import Project="$(MSBuildThisFileDirectory)EmSdkRepo.Defaults.props" Condition="'$(WasmUseEMSDK_PATH)' == 'true'" />
   <Target Name="_SetupEmscripten" BeforeTargets="_SetupToolchain">
     <PropertyGroup>

src/mono/nuget/Microsoft.NET.Runtime.WebAssembly.Sdk/Sdk/Sdk.props

@@ -3,6 +3,5 @@
     <TargetArchitecture>wasm</TargetArchitecture>
     <TargetOS>browser</TargetOS>
     <OutputType Condition="'$(OutputType)' == ''">Exe</OutputType>
-    <PublishTrimmed Condition="'$(PublishTrimmed)' == ''">true</PublishTrimmed>
   </PropertyGroup>
 </Project>

src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.targets

@@ -1245,4 +1245,11 @@ Copyright (c) .NET Foundation. All rights reserved.
           Condition="Exists('$(_DotnetTypesSourcePath)')"
           SkipUnchangedFiles="true" />
   </Target>
+
+  <!-- When trimming non-exe projects, root the whole intermediate assembly. -->
+  <Target Name="_RootEntireIntermediateAssembly" AfterTargets="PrepareForILLink" BeforeTargets="_RunILLink" Condition="'$(RuntimeIdentifier)' == 'browser-wasm' And '$(OutputType)' == 'Library'">
+    <ItemGroup>
+      <TrimmerRootAssembly Include="$(AssemblyName)" RootMode="all" />
+    </ItemGroup>
+  </Target>
 </Project>

src/mono/nuget/Microsoft.NET.Workload.Mono.Toolchain.Current.Manifest/WorkloadManifest.targets.in

@@ -37,7 +37,6 @@
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(RuntimeIdentifier)' == 'browser-wasm'">
-    <SelfContained>true</SelfContained>
     <WasmNativeWorkloadAvailable Condition="'$(TargetsCurrent)' == 'true'">$(WasmNativeWorkload11)</WasmNativeWorkloadAvailable>
     <WasmNativeWorkloadAvailable Condition="'$(TargetsNet10)' == 'true'">$(WasmNativeWorkload10)</WasmNativeWorkloadAvailable>
     <WasmNativeWorkloadAvailable Condition="'$(TargetsNet9)' == 'true'">$(WasmNativeWorkload9)</WasmNativeWorkloadAvailable>
@@ -64,7 +63,6 @@
         '$(WasmProfilers)' != '' or
         '$(RunAOTCompilation)' == 'true' or
         '$(WasmBuildNative)' == 'true' or
-        '$(_UsingBlazorOrWasmSdk)' != 'true' or
         '$(EmccInitialHeapSize)' != '' or
         '$(EmccMaximumHeapSize)' != '' " >true</_WasmNativeWorkloadNeeded>
 

src/mono/wasm/Wasm.Build.Tests/Templates/WasmTemplateTests.cs

@@ -300,10 +300,12 @@ void AssertFile(string suffix)
             }
         }
 
-        [Theory]
-        // [InlineData(false)] https://github.com/dotnet/runtime/issues/123477
-        [InlineData(true)]
-        public async Task LibraryModeBuild(bool useWasmSdk)
+        [Theory, TestCategory("no-workload")]
+        [InlineData(false, false)]
+        [InlineData(false, true)]
+        [InlineData(true, false)]
+        [InlineData(true, true)]
+        public async Task LibraryMode(bool useWasmSdk, bool isPublish)
         {
             var config = Configuration.Release;
             ProjectInfo info = CopyTestAsset(config, aot: false, TestAsset.LibraryModeTestApp, "libraryMode");
@@ -313,13 +315,22 @@ public async Task LibraryModeBuild(bool useWasmSdk)
                     { "Microsoft.NET.Sdk.WebAssembly", "Microsoft.NET.Sdk" }
                 });
             }
-            BuildProject(info, config, new BuildOptions(AssertAppBundle: useWasmSdk));
+
+            // Without WASM SDK, the project is a plain library with browser-wasm RID.
+            // It should build and publish successfully but won't produce a wasm app bundle.
+            if (isPublish)
+                PublishProject(info, config, new PublishOptions(AssertAppBundle: useWasmSdk));
+            else
+                BuildProject(info, config, new BuildOptions(AssertAppBundle: useWasmSdk));
+
             if (useWasmSdk)
             {
-                var result = await RunForBuildWithDotnetRun(new BrowserRunOptions(config, ExpectedExitCode: 100));
+                var result = isPublish
+                    ? await RunForPublishWithWebServer(new BrowserRunOptions(config, ExpectedExitCode: 100))
+                    : await RunForBuildWithDotnetRun(new BrowserRunOptions(config, ExpectedExitCode: 100));
+
                 Assert.Contains("WASM Library MyExport is called", result.TestOutput);
             }
-            
         }
 
         [Theory]

src/mono/wasm/testassets/WasmBasicTestApp/LazyLibrary/LazyLibrary.csproj

@@ -4,6 +4,5 @@
     <RuntimeIdentifier>browser-wasm</RuntimeIdentifier>
     <OutputType>Library</OutputType>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
-    <UseMonoRuntime>true</UseMonoRuntime>
   </PropertyGroup>
 </Project>