Non-determenistics build order results in failed builds

[m-novikov]

Actual Behavior

conda build spontaneously fails when building two packages from one recipe

Expected Behavior

conda build should succeed

Steps to Reproduce

The recipe run enough times.
This build recipe includes two packages: testpkg and testpkg-client.

Problem:

The build order of these packages is non-determenistic as function render_recipe may return results in arbitrary order.

Build order: testpkg-client, testpkg

When conda build decides that it wants to build testpkg-client as a first package and recipe has GIT_* variables in it it will trigger execution this line which tries to move work dir to another location.
But as the work directory already exists it results in nested path work/work which makes directory not installable or prevents population of environment variables.

When I tried to fix it replacing offending move line with following code:

if old_dir:
    dst = self.work_dir   # Calls _ensure_dir and creates directory
    shutil.rmtree(dst)     # Remove directory to allow proper move
    shutil.move(old_dir, dst)

It builds the package, but fails on test stage, where test enviroment still installs testpkg instead of testpkg-client.
Removing GIT_* from recipe variables also results in this error.

Build order: testpkg, testpkg-client

Everything built and tested as expected without any problems.

Output of conda info

     active environment : base
    active env location : /home/novikov/tools/miniconda3
            shell level : 1
       user config file : /home/novikov/.condarc
 populated config files : /home/novikov/.condarc
          conda version : 4.7.5
    conda-build version : 3.18.7
         python version : 3.7.3.final.0
       virtual packages : __cuda=10.2
       base environment : /home/novikov/tools/miniconda3  (writable)
           channel URLs : https://repo.anaconda.com/pkgs/main/linux-64
                          https://repo.anaconda.com/pkgs/main/noarch
                          https://repo.anaconda.com/pkgs/r/linux-64
                          https://repo.anaconda.com/pkgs/r/noarch
          package cache : /home/novikov/tools/miniconda3/pkgs
                          /home/novikov/.conda/pkgs
       envs directories : /home/novikov/tools/miniconda3/envs
                          /home/novikov/.conda/envs
               platform : linux-64
             user-agent : conda/4.7.5 requests/2.22.0 CPython/3.7.3 Linux/5.2.0-arch2-1-ARCH arch/ glibc/2.29
                UID:GID : 1000:1000
             netrc file : None
           offline mode : False

[github-actions]

Hi there, thank you for your contribution!

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