Added ability to collect test cases by topology mark (#2640)

We do have ability run TC with --topology t0,t1 etc. argument. But if we want to collect which cases support for example t0 topo without execution, option --collect-only always returns all available tests in module/folder. PR resolves this problem.

What is the motivation for this PR?
Can not collect test cases based on topology.

How did you do it?
Enhanced check_topology method.
Added pytest_collection_modifyitems hook.

Signed-off-by: Roman Savchuk <romanx.savchuk@intel.com>

tests/common/plugins/custom_markers/__init__.py

@@ -41,9 +41,12 @@ def pytest_configure(config):
  "markers", "supported_completeness_level(TEST_LEVEL): mark test to specify the completeness level for the test. Allowed values: 'debug', 'basic' ,'confident', 'thorough'"
  )
 
+def pytest_collection_modifyitems(session):
+ if session.config.getoption("--topology"):
+ for item in session.items[:]:
+ check_topology(session, item)
+
 def pytest_runtest_setup(item):
- if item.config.getoption("--topology"):
- check_topology(item)
  if item.config.getoption("--feature"):
  check_feature(item)
  if item.config.getoption("--asic"):
@@ -55,19 +58,27 @@ def pytest_runtest_setup(item):
 
  check_test_completeness(item)
 
-def check_topology(item):
+def check_topology(session, item):
  # The closest marker is used here so that the module or class level
  # marker will be overrided by case level marker
  topo_marks = [mark for mark in item.iter_markers(name="topology")] # Get all 'topology' marks on the chain
  if topo_marks:
  topo_mark = topo_marks[0] # The nearest mark overides others
- cfg_topos = item.config.getoption("--topology").split(',')
+ cfg_topos = session.config.getoption("--topology").split(',')
  if all(topo not in topo_mark.args for topo in cfg_topos):
- pytest.skip("test requires topology in {!r}".format(topo_mark))
+ if session.config.getoption("--collectonly"):
+ session.items.remove(item)
+ session.config.hook.pytest_deselected(items=[item])
+ else:
+ item.add_marker(pytest.mark.skip("test requires topology in {!r}".format(topo_mark)))
  else:
- warn_msg = "testcase {} is skipped when no topology marker is given".format(item.nodeid)
- warnings.warn(warn_msg)
- pytest.skip(warn_msg)
+ if session.config.getoption("--collectonly"):
+ session.items.remove(item)
+ session.config.hook.pytest_deselected(items=[item])
+ else:
+ warn_msg = "testcase {} is skipped when no topology marker is given".format(item.nodeid)
+ warnings.warn(warn_msg)
+ item.add_marker(pytest.mark.skip(warn_msg))
 
 def check_feature(item):
  feature_names = [mark.args for mark in item.iter_markers(name="feature")]