Can't use Microsoft.CodeAnalysis.Common on .Net 4.5

Description

The Microsoft.CodeAnalysis.Common package reference System.Reflection.Metadata conditionally depending on the framework version and paket doesn't seem to handle it well.

Repro steps

• Use the following dependencies:

redirects: on
source https://nuget.org/api/v2
nuget Microsoft.CodeAnalysis.Common ~> 1.3.2

• Run paket install
• Observe that paket.lock has an incorrect framework restriction on the System.Reflection.Metadata package making it inaccessible to .Net 4.5 (But the package is compatible and referenced by a package that is also compatible) :

System.Reflection.Metadata (1.3) - framework: >= net46, >= netstandard13

It seem to have used only one restriction from Microsoft.CodeAnalysis.Common dependencies instead of merging them all :

    Microsoft.CodeAnalysis.Common (1.3.2)
      ...
      System.Reflection.Metadata (>= 1.2) - framework: portable-net45+win8
      System.Reflection.Metadata (>= 1.3) - framework: >= net46, >= netstandard13

Expected behavior

Transitive dependencies are correctly detected and installed in the project.

Actual behavior

As no reference is created to the transitive dependency the dll isn't included and the code would crash at runtime.

Known workarounds

Using project.json ?

More seriously, I tried to specify a very specific framework for the dependency :

nuget System.Reflection.Metadata framework: portable-net45+win8

But while the lock file now include that one, the msbuild produced still doesn't want to do what I want :

<When Condition="($(TargetFrameworkProfile) == 'Profile7') Or ($(TargetFrameworkProfile) == 'Profile44')">

For now i'll remove the dependency and reference the whole transitive graph by hand.

Start by reproducing the paket install with Microsoft.CodeAnalysis.Common 1.3.2 and inspect the generated paket.lock restriction for System.Reflection.Metadata. Trace how the two dependency restrictions are combined, then verify that the resulting lock file and MSBuild output make the transitive dependency available to .NET 4.5.