tests/test_vagrant.py: Allow to set provider from env variables

Current provider is hardcoded inside the test file. We may want
to switch easily between test providers (local testing, using
something else than GHA, whatever...) so add a new function used
to return the current test provider.

Changing the test provider is done by setting an environment variable
since any code / logic to detect the provider to use will always
be broken.

Signed-off-by: Arnaud Patard <apatard@hupstream.com>

Author: apatard

tests/test_vagrant.py

@@ -30,6 +30,20 @@
 import vagrant
 from vagrant import compat
 
+
+# must be defined before TEST_PROVIDER.
+def get_provider() -> str:
+    """
+    Return the provider to use for testing and allow to set it
+    with PYTHON_VAGRANT_TEST_PROVIDER environment variable is set.
+    Defauts to virtualbox
+    """
+    my_prov = "virtualbox"
+    if "PYTHON_VAGRANT_TEST_PROVIDER" in os.environ:
+        my_prov = os.environ["PYTHON_VAGRANT_TEST_PROVIDER"]
+    return my_prov
+
+
 # location of Vagrant executable
 VAGRANT_EXE = vagrant.get_vagrant_executable()
 
@@ -53,7 +67,7 @@
 # name of the base box used for testing
 TEST_BOX_URL = "generic/alpine315"
 TEST_BOX_NAME = TEST_BOX_URL
-TEST_PROVIDER = "virtualbox"
+TEST_PROVIDER = get_provider()
 TEST_DUMMY_BOX_URL = os.path.join(
     os.path.dirname(os.path.abspath(__file__)), "tools", f"dummy-{TEST_PROVIDER}.box"
 )

tox.ini

@@ -26,6 +26,7 @@ commands =
     --no-cov-on-fail \
   }
 passenv =
+    PYTHON_VAGRANT_TEST_PROVIDER
     # Pass HOME to the test environment as it is required by
     # vagrant. Otherwise error happens due to missing HOME env variable.
     HOME