.NET: Make GitHub.Copilot.SDK build targets reach transitive consumers (#6455)

dotnet/src/Microsoft.Agents.AI.GitHub.Copilot/Microsoft.Agents.AI.GitHub.Copilot.csproj

@@ -32,4 +32,52 @@
     <Description>Provides Microsoft Agent Framework support for GitHub Copilot SDK.</Description>
   </PropertyGroup>
 
+  <!--
+    buildTransitive bridge for GitHub.Copilot.SDK's CLI binary-download targets.
+
+    GitHub.Copilot.SDK ships its CLI download targets under build/, which NuGet
+    only auto-imports for projects with a DIRECT PackageReference to the SDK.
+    Consumers of this package (who reference Microsoft.Agents.AI.GitHub.Copilot
+    instead of GitHub.Copilot.SDK directly) would otherwise get only the managed
+    adapter .dll, no copilot.exe in their output, and a runtime failure at the
+    first RunAsync call.
+
+    The targets file in buildTransitive/ is static and contains all of the
+    Condition / Import logic. The .props file generated here just bakes the
+    SDK version this package was built against into a dedicated property
+    ($(_MicrosoftAgentsAICopilotSdkPackagedVersion)) — no Condition or
+    inner $(...) reference in the generated file, so we avoid any MSBuild
+    escape gymnastics during string construction. The static targets file
+    then defaults $(_MicrosoftAgentsAICopilotSdkVersion) to the packaged
+    version unless the consumer overrides it.
+  -->
+  <ItemGroup>
+    <None Include="buildTransitive\Microsoft.Agents.AI.GitHub.Copilot.targets" Pack="true" PackagePath="buildTransitive\" />
+    <None Include="buildTransitive\Microsoft.Agents.AI.GitHub.Copilot.props" Pack="true" PackagePath="buildTransitive\" />
+  </ItemGroup>
+
+  <Target Name="_GenerateBuildTransitiveProps" BeforeTargets="Build;Pack;_GetPackageFiles">
+    <ItemGroup>
+      <_CopilotSdkPackageVersion Include="@(PackageVersion)" Condition="'%(Identity)' == 'GitHub.Copilot.SDK'" />
+    </ItemGroup>
+    <PropertyGroup>
+      <_CopilotSdkResolvedVersion>@(_CopilotSdkPackageVersion->'%(Version)')</_CopilotSdkResolvedVersion>
+    </PropertyGroup>
+    <Error Condition="'$(_CopilotSdkResolvedVersion)' == ''"
+           Text="Could not resolve GitHub.Copilot.SDK version from PackageVersion items. Ensure the central package version is declared in Directory.Packages.props." />
+    <PropertyGroup>
+      <_BuildTransitivePropsContent>
+<![CDATA[<Project>
+  <PropertyGroup>
+    <_MicrosoftAgentsAICopilotSdkPackagedVersion>$(_CopilotSdkResolvedVersion)</_MicrosoftAgentsAICopilotSdkPackagedVersion>
+  </PropertyGroup>
+</Project>]]>
+      </_BuildTransitivePropsContent>
+    </PropertyGroup>
+    <WriteLinesToFile File="$(MSBuildThisFileDirectory)buildTransitive\Microsoft.Agents.AI.GitHub.Copilot.props"
+                      Lines="$(_BuildTransitivePropsContent)"
+                      Overwrite="true"
+                      WriteOnlyWhenDifferent="true" />
+  </Target>
+
 </Project>

dotnet/src/Microsoft.Agents.AI.GitHub.Copilot/buildTransitive/.gitignore

@@ -0,0 +1,3 @@
+# Auto-generated at pack time by _GenerateBuildTransitiveProps in the csproj.
+Microsoft.Agents.AI.GitHub.Copilot.props
+

dotnet/src/Microsoft.Agents.AI.GitHub.Copilot/buildTransitive/Microsoft.Agents.AI.GitHub.Copilot.targets

@@ -0,0 +1,34 @@
+<Project>
+  <!--
+    Bridge GitHub.Copilot.SDK's build/ targets to transitive consumers.
+
+    GitHub.Copilot.SDK ships its CLI download / binary-copy MSBuild targets under
+    build/, which means they only auto-import for projects with a DIRECT
+    PackageReference to GitHub.Copilot.SDK. Consumers of this package
+    (Microsoft.Agents.AI.GitHub.Copilot) would otherwise get only the managed
+    adapter .dll, no copilot CLI binary in their output, and the SDK would fail
+    at runtime with:
+
+        Copilot CLI not found at 'bin/{config}/{tfm}/runtimes/{rid}/native/copilot.exe'
+
+    This file ships under buildTransitive/ so NuGet auto-imports it for every
+    transitive consumer, locates the SDK in the NuGet package cache, and imports
+    the SDK's build/ targets so the CLI binary gets downloaded and copied to the
+    consumer's output as expected.
+
+    The companion .props file is generated at this package's pack time and sets
+    $(_MicrosoftAgentsAICopilotSdkPackagedVersion) to the SDK version this
+    package was built against. The Condition below uses that as the default for
+    $(_MicrosoftAgentsAICopilotSdkVersion), so consumers may override the SDK
+    version path by setting $(_MicrosoftAgentsAICopilotSdkVersion) before this
+    file is imported. Consumers may also opt out of the binary download via the
+    SDK's own $(CopilotSkipCliDownload)=true, which the SDK targets honor.
+  -->
+  <PropertyGroup>
+    <_MicrosoftAgentsAICopilotSdkVersion Condition="'$(_MicrosoftAgentsAICopilotSdkVersion)' == ''">$(_MicrosoftAgentsAICopilotSdkPackagedVersion)</_MicrosoftAgentsAICopilotSdkVersion>
+    <_MicrosoftAgentsAICopilotSdkTargetsPath Condition="'$(_MicrosoftAgentsAICopilotSdkVersion)' != ''">$([System.IO.Path]::Combine('$(NuGetPackageRoot)', 'github.copilot.sdk', '$(_MicrosoftAgentsAICopilotSdkVersion)', 'build', 'GitHub.Copilot.SDK.targets'))</_MicrosoftAgentsAICopilotSdkTargetsPath>
+  </PropertyGroup>
+
+  <Import Project="$(_MicrosoftAgentsAICopilotSdkTargetsPath)"
+          Condition="'$(_MicrosoftAgentsAICopilotSdkTargetsPath)' != '' And Exists('$(_MicrosoftAgentsAICopilotSdkTargetsPath)')" />
+</Project>