Weave assemblies only if they do not already exist

[BlinD-HuNTeR]

Currently the MTP_AssembliesWeaverTask task is invoked every time the project is compiled, which not only imposes an overhead but also breaks incremental compilation.

By adding the following target to my project, I was able to make this task be invoked only for assemblies that don't already exist:

    <Target
        Name="MTP_ExistingReferences"
        Condition="$(IgnoreAccessChecks) == 'true'"
        DependsOnTargets="MTP_GetSourceReferences;MTP_GetTargetReferences;MTP_DisableAccessChecks_Runtime"
        BeforeTargets="MTP_DisableAccessChecks">

        <ItemGroup>
            <MTP_ExistingSourceReferences Include="@(MTP_SourceReferences)" Condition="Exists('$(BaseIntermediateOutputPath)MakeTypesPublic\Assemblies\%(Filename)%(Extension)')" />
            <MTP_ExistingTargetReferences Include="@(MTP_TargetReferences->Exists())" />
            <MTP_SourceReferences Remove="@(MTP_ExistingSourceReferences)" />
            <MTP_TargetReferences Remove="@(MTP_ExistingTargetReferences)" />
            <ReferencePath Remove="@(MTP_ExistingSourceReferences)" />
            <ReferencePath Include="@(MTP_ExistingTargetReferences)" />
        </ItemGroup>
    </Target>

With this target in place, assemblies don't get weaved on every compilation. Everything works fine, and incremental compilation starts working again.

Also you can even enable weaving at design-time with no drawbacks. You can probably even remove the IgnoreAccessChecks property and make this the defaut behaviour.