Add StaticWebAssetMakeReferencedAssetOriginalItemSpecAbsolute property to WasmSdk

[Copilot]

This PR fixes an issue where web applications referencing Sdk.WebAssembly projects fail to build with the error "The UpdateExternallyDefinedStaticWebAssets task failed unexpectedly". The error occurs because the WasmSdk was missing the StaticWebAssetMakeReferencedAssetOriginalItemSpecAbsolute property that is already present in the BlazorWebAssembly SDK.

The fix adds the missing property to /src/WasmSdk/Sdk/Sdk.props:

<StaticWebAssetMakeReferencedAssetOriginalItemSpecAbsolute Condition="'$(StaticWebAssetMakeReferencedAssetOriginalItemSpecAbsolute)' == ''">true</StaticWebAssetMakeReferencedAssetOriginalItemSpecAbsolute>

This ensures consistency between the WasmSdk and BlazorWebAssembly SDK implementations and allows static web assets to resolve file paths correctly when processing externally defined assets.

The property includes a conditional check to avoid overriding any user-defined values, following the same pattern used in the BlazorWebAssembly SDK.

Fixes dotnet/runtime#118393, dotnet/aspnetcore#62915

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[Copilot]

Pull Request Overview

This PR fixes a build failure in web applications that reference Sdk.WebAssembly projects by adding a missing property to the WasmSdk. The error "The UpdateExternallyDefinedStaticWebAssets task failed unexpectedly" occurred because the WasmSdk lacked a property that was already present in the BlazorWebAssembly SDK.

• Adds StaticWebAssetMakeReferencedAssetOriginalItemSpecAbsolute property to WasmSdk
• Ensures consistency between WasmSdk and BlazorWebAssembly SDK implementations
• Includes conditional check to avoid overriding user-defined values

Comments suppressed due to low confidence (1)

src/WasmSdk/Sdk/Sdk.props:29

• This property addition should include test coverage to verify that it resolves the build failure when web applications reference Sdk.WebAssembly projects. Consider adding a test that validates the property is set correctly and that the UpdateExternallyDefinedStaticWebAssets task succeeds.

    <StaticWebAssetMakeReferencedAssetOriginalItemSpecAbsolute Condition="'$(StaticWebAssetMakeReferencedAssetOriginalItemSpecAbsolute)' == ''">true</StaticWebAssetMakeReferencedAssetOriginalItemSpecAbsolute>

[pavelsavara]

There are more defaults. Should we use them all ?

sdk/src/BlazorWasmSdk/Targets/Microsoft.NET.Sdk.BlazorWebAssembly.Current.props

Lines 28 to 34 in a6d225e

	<!-- Static web assets defaults -->
	<StaticWebAssetProjectMode Condition="'$(StaticWebAssetProjectMode)' == ''">Root</StaticWebAssetProjectMode>
	<StaticWebAssetsAdditionalPublishProperties>$(StaticWebAssetsAdditionalPublishProperties);_PublishingBlazorWasmProject=true</StaticWebAssetsAdditionalPublishProperties>
	<StaticWebAssetsAdditionalEmbeddedPublishProperties>$(StaticWebAssetsAdditionalEmbeddedPublishProperties);_PublishingBlazorWasmProject=true</StaticWebAssetsAdditionalEmbeddedPublishProperties>
	<StaticWebAssetStandaloneHosting Condition="'$(StaticWebAssetStandaloneHosting)' == '' and '$(StaticWebAssetProjectMode)' == 'Root'">true</StaticWebAssetStandaloneHosting>
	<StaticWebAssetMakeReferencedAssetOriginalItemSpecAbsolute Condition="'$(StaticWebAssetMakeReferencedAssetOriginalItemSpecAbsolute)' == ''">true</StaticWebAssetMakeReferencedAssetOriginalItemSpecAbsolute>
	<StaticWebAssetsGetEmbeddedPublishAssetsTargets>ComputeFilesToPublish;GetCurrentProjectEmbeddedPublishStaticWebAssetItems</StaticWebAssetsGetEmbeddedPublishAssetsTargets>

[ilonatommy]

There are more defaults. Should we use them all ?

sdk/src/BlazorWasmSdk/Targets/Microsoft.NET.Sdk.BlazorWebAssembly.Current.props

Lines 28 to 34 in a6d225e

	<!-- Static web assets defaults -->
	<StaticWebAssetProjectMode Condition="'$(StaticWebAssetProjectMode)' == ''">Root</StaticWebAssetProjectMode>
	<StaticWebAssetsAdditionalPublishProperties>$(StaticWebAssetsAdditionalPublishProperties);_PublishingBlazorWasmProject=true</StaticWebAssetsAdditionalPublishProperties>
	<StaticWebAssetsAdditionalEmbeddedPublishProperties>$(StaticWebAssetsAdditionalEmbeddedPublishProperties);_PublishingBlazorWasmProject=true</StaticWebAssetsAdditionalEmbeddedPublishProperties>
	<StaticWebAssetStandaloneHosting Condition="'$(StaticWebAssetStandaloneHosting)' == '' and '$(StaticWebAssetProjectMode)' == 'Root'">true</StaticWebAssetStandaloneHosting>
	<StaticWebAssetMakeReferencedAssetOriginalItemSpecAbsolute Condition="'$(StaticWebAssetMakeReferencedAssetOriginalItemSpecAbsolute)' == ''">true</StaticWebAssetMakeReferencedAssetOriginalItemSpecAbsolute>
	<StaticWebAssetsGetEmbeddedPublishAssetsTargets>ComputeFilesToPublish;GetCurrentProjectEmbeddedPublishStaticWebAssetItems</StaticWebAssetsGetEmbeddedPublishAssetsTargets>

Good question. StaticWebAssetsAdditionalPublishProperties and StaticWebAssetsAdditionalEmbeddedPublishProperties look like blazor-specific. The rest can probably be added for pure wasm.

Edit:
some of them are already set in https://github.com/dotnet/runtime/blob/123627ba0f80c268cbde5beb6db42dc5c12d150d/src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.props#L34
Now I'm not that confident if I'm making the change in the right place. It should probably be with other default props in the runtime.

Props that do not look blazor-specific and are not set, neither in sdk nor in runtime:

• StaticWebAssetMakeReferencedAssetOriginalItemSpecAbsolute
• StaticWebAssetsGetEmbeddedPublishAssetsTargets

I would wait for @maraf with the decision.

[javiercn]

There are similar properties in the Blazor WebAssembly SDK, we should remove them from there since that SDK imports this SDK and they are no longer needed

[javiercn]

@copilot fix it

[javiercn]

No, we don't care about the remaining defaults, they are Blazor specific

[maraf]

We should move the setting to https://github.com/dotnet/runtime/blob/main/src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.props#L32-L39 if having the property set only after the nuget packages are restored is early enough

[javiercn]

We should move the setting to https://github.com/dotnet/runtime/blob/main/src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.props#L32-L39 if having the property set only after the nuget packages are restored is early enough

It should be