Merge pull request conda#9349 from beckermr/osx-virt

ENH add osx version virtual package

conda/common/compat.py

@@ -16,6 +16,7 @@
 
 on_win = bool(sys.platform == "win32")
 on_mac = bool(sys.platform == "darwin")
+on_linux = bool(sys.platform == "linux")
 
 PY2 = sys.version_info[0] == 2
 PY3 = sys.version_info[0] == 3

conda/core/index.py

@@ -159,6 +159,13 @@ def _supplement_index_with_system(index):
         rec = _make_virtual_package('__cuda', cuda_version)
         index[rec] = rec
 
+    dist_name, dist_version = context.os_distribution_name_version
+    if dist_name == 'OSX':
+        dist_version = os.environ.get('CONDA_OVERRIDE_OSX', dist_version)
+        if len(dist_version) > 0:
+            rec = _make_virtual_package('__osx', dist_version)
+            index[rec] = rec
+
     libc_family, libc_version = context.libc_family_version
     if libc_family and libc_version:
         libc_version = os.getenv("CONDA_OVERRIDE_{}".format(libc_family.upper()), libc_version)

docs/source/user-guide/tasks/manage-virtual.rst

@@ -14,6 +14,7 @@ small bit of code to detect the presence or absence of the system feature that
 corresponds to the package.  The currently supported list of virtual packages includes:
 
   * ``__cuda``: Maximum version of CUDA supported by the display driver
+  * ``__osx``: OSX version if applicable
   * ``__glibc``: Version of glibc supported by the OS
 
 Other virtual packages will be added in future conda releases.  These are denoted
@@ -69,5 +70,7 @@ using an environment variable.  Supported variables include:
 
 * ``CONDA_OVERRIDE_CUDA`` - CUDA version number or set to ``""`` for no CUDA
   detected.
+* ``CONDA_OVERRIDE_OSX`` - OSX version number or set to ``""`` for no OSX
+  detected.
 * ``CONDA_OVERRIDE_GLIBC`` - GLIBC version number or set to ``""`` for no GLIBC.
   This only applies on Linux.

tests/core/test_index.py

@@ -8,7 +8,7 @@
 
 from conda.base.constants import DEFAULT_CHANNELS
 from conda.base.context import context, Context, conda_tests_ctxt_mgmt_def_pol
-from conda.common.compat import iteritems, on_win, on_mac
+from conda.common.compat import iteritems, on_win, on_mac, on_linux
 from conda.common.io import env_vars
 from conda.core.index import check_whitelist, get_index, get_reduced_index, _supplement_index_with_system
 from conda.exceptions import ChannelNotAllowed
@@ -54,6 +54,17 @@ def test_supplement_index_with_system_cuda():
     assert cuda_pkg.package_type == PackageType.VIRTUAL_SYSTEM
 
 
+@pytest.mark.skipif(not on_mac, reason="osx-only test")
+def test_supplement_index_with_system_osx():
+      index = {}
+      with env_vars({'CONDA_OVERRIDE_OSX': '0.15'}):
+          _supplement_index_with_system(index)
+
+      osx_pkg = next(iter(_ for _ in index if _.name == '__osx'))
+      assert osx_pkg.version == '0.15'
+      assert osx_pkg.package_type == PackageType.VIRTUAL_SYSTEM
+
+
 @pytest.mark.skipif(on_win or on_mac, reason="linux-only test")
 def test_supplement_index_with_system_glibc():
     index = {}