NuGet Packages for unstable, in-development Libraries – cont. (III)

Previously, I wrote about using one global msbuild xml file to override nuget package content for local development. While this does work, it comes with a warning if multiple packages use this mechanism:

***Test\packages\***.0.7.1-prerelease-\build\native\***.targets(7,5):
warning MSB4011: "***Test\packagesoverride.xml.user" cannot be imported again. It was already imported at "***Test\packages\***.0.7.1-prerelease-\build\native\***.targets (6,3)".
This is most likely a build authoring error. This subsequent import will be ignored. [***Test\***Test.vcxproj]

While this is not realy a problem, it is a warning. And I don’t like warning. I like my projects to build entirly without warnings.

A soltion for this comes from classic c++ programming: use an include guard. These are the changes required:

The packagesoverride.xml.user must define a default variable. I named it HAS_packagesoverride:

<?xml version="1.0" encoding="utf-8"?>
<Project ToolsVersion="15.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <PropertyGroup>
    <HAS_packagesoverride>True</HAS_packagesoverride>
    <NugetDevPackageTest_testLib_DevDir>C:\Dev\SomeProject\Dir</NugetDevPackageTest_testLib_DevDir>
  </PropertyGroup>
</Project>

And now importing this xml in the nuget packages’ target files can this for this variable to avoid multiple import:

<?xml version="1.0" encoding="utf-8"?>
<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003" InitialTargets="FaroMorfCopySymbols">

  <!-- Import override settings, if they exist -->
  <ImportGroup>
    <Import
      Condition="Exists('$(SolutionDir)packagesoverride.xml.user') and '$(HAS_packagesoverride)' != 'True'"
      Project="$(SolutionDir)packagesoverride.xml.user" />
  </ImportGroup>

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