From 8ef530a00a8251f40af4ca86fe1504496b4dcc76 Mon Sep 17 00:00:00 2001
From: Larry Ewing <lewing@microsoft.com>
Date: Fri, 6 Feb 2026 14:48:02 -0600
Subject: [PATCH] Fix invalid MSBuild ItemGroup syntax in WASM HotReload

The code was using:
  <_WasmHotReloadModule OriginalItemSpec="%(Identity)" />

This creates a new empty item instead of setting metadata on the existing item.

Fixed to use proper MSBuild Update syntax:
  <_WasmHotReloadModule Update="@(_WasmHotReloadModule)">
    <OriginalItemSpec>%(Identity)</OriginalItemSpec>
  </_WasmHotReloadModule>

This issue was introduced in #52816 and could cause DefineStaticWebAssets
to receive empty items, leading to potential build failures or incorrect
static web asset processing.
---
 src/WasmSdk/Sdk/Sdk.targets | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/WasmSdk/Sdk/Sdk.targets b/src/WasmSdk/Sdk/Sdk.targets
index e69f3f2d5b3f..d566696af777 100644
--- a/src/WasmSdk/Sdk/Sdk.targets
+++ b/src/WasmSdk/Sdk/Sdk.targets
@@ -42,7 +42,9 @@ Copyright (c) .NET Foundation. All rights reserved.
       <_WasmHotReloadModule Include="$(_WasmHotReloadIntermediatePath)Microsoft.DotNet.HotReload.WebAssembly.Browser.lib.module.js">
         <RelativePath>_framework/Microsoft.DotNet.HotReload.WebAssembly.Browser.lib.module.js</RelativePath>
       </_WasmHotReloadModule>
-      <_WasmHotReloadModule OriginalItemSpec="%(Identity)" />
+      <_WasmHotReloadModule Update="@(_WasmHotReloadModule)">
+        <OriginalItemSpec>%(Identity)</OriginalItemSpec>
+      </_WasmHotReloadModule>
       <FileWrites Include="$(_WasmHotReloadIntermediatePath)Microsoft.DotNet.HotReload.WebAssembly.Browser.lib.module.js" />
     </ItemGroup>