podman: skip tests with unsupported versions

Podman tests would fail with older version of podman due to missing
cp command.

Now we also check the version and skip the tests if installed version
is too old.

.travis.yml

@@ -362,5 +362,7 @@ before_install:
 script:
   # keep it like this to first create env and later to run again with tests
   # in order to avoid regressions to run twice on the same environment.
+  - podman version
+  - docker version
   - tox --notest
   - tox

molecule/test/functional/conftest.py

@@ -20,10 +20,12 @@
 #  DEALINGS IN THE SOFTWARE.
 
 import distutils.spawn
+from distutils.version import LooseVersion
 import os
 import pkg_resources
 import platform
 import shutil
+import subprocess
 
 import pexpect
 import pytest
@@ -38,6 +40,9 @@
 LOG = logger.get_logger(__name__)
 
 IS_TRAVIS = os.getenv('TRAVIS') and os.getenv('CI')
+# requires >=1.5.1 due to missing cp command, we tested with 1.4.2-stable3 and
+# it failed, see https://bugzilla.redhat.com/show_bug.cgi?id=1759713
+MIN_PODMAN_VERSION = "1.5.1"
 
 
 @pytest.fixture(scope="session", autouse=True)
@@ -302,6 +307,21 @@ def supports_podman():
         pytest.fail("Cannot run podman tests with a broken podman installation.")
         return False
 
+    # checks for minimal version of podman
+    cmd = ["podman", "version", "-f", "{{.Version}}"]
+    podman_version = util.check_output(
+        cmd, stderr=subprocess.STDOUT, universal_newlines=True
+    )
+    # We need to use the outdated LooseVersion because podman versioning
+    # is not PEP-440 compliant, example '1.4.2-stable3' which should evaluate
+    # as newer than '1.4.2'
+    if LooseVersion(podman_version) < LooseVersion(MIN_PODMAN_VERSION):
+        pytest.skip(
+            "Podman driver requires version >={}, and you have {}".format(
+                MIN_PODMAN_VERSION, podman_version
+            )
+        )
+
     return True