Finding alternate object directories on open

Git 2.11 introduced a change such that incoming objects in a push are sequestered in an "alternate object directory." It appears that libgit2 supports opening repositories with these directories, taking certain environment variables into consideration, but the latest pygit2 does not invoke the appropriate function (git_repository_open_ext() from what I can tell). Am I correct in this assessment? Is there a way to work around this with the current code, or is a patch necessary?

If that didn't make sense, let me explain at a higher level: I'm writing a receive hook in Python and using pygit2 to examine the incoming commits. With versions of Git prior to 2.11 this is not a problem since the incoming objects are stored directly in the odb. However, now they are located elsewhere and pygit2 does not see them.

Beginne damit nachzuverfolgen, wie pygit2 Repositorys öffnet, und vergleiche diesen Pfad mit libgit2s git_repository_open_ext(), einschließlich der in diesem Issue beschriebenen Umgebungsvariablen. Überprüfe den receive-hook-Fall, bei dem eingehende Objekte in einem alternativen Objektverzeichnis liegen; fertig ist die Aufgabe, wenn pygit2 diese Commits untersuchen kann.