feat(test_build_system): add buildv2_skip marker

This marker enables the skipping of tests that, for any reason, cannot
be executed with the IDF build system version 2. It accepts an optional
string argument that explains why the test cannot be run with version 2.
If no explanation is provided, a default message is used. This marker is
used in the `pytest_collection_modifyitems` hook to skip tests marked
with it when the `--buildv2` pytest command line option is used.

Signed-off-by: Frantisek Hrbata <frantisek.hrbata@espressif.com>

tools/test_build_system/README.md

@@ -131,6 +131,24 @@ def test_idf_copy(idf_copy):
     run_idf_py('build', env=env)
 ```
 
+### `buildv2_skip` marker
+
+This marker enables the skipping of tests that, for any reason, cannot be
+executed with the IDF build system version 2. It accepts an optional string
+argument that explains why the test cannot be run with version 2. If no
+explanation is provided, a default message is used. This marker is used in
+the `pytest_collection_modifyitems` hook to skip tests marked with it when the
+`--buildv2` pytest command line option is used. For implementation details,
+please refer to `conftest.py`.
+
+```python
+@pytest.mark.buildv2_skip
+def test_target_guessing()
+
+@pytest.mark.buildv2_skip('This functionality has not been implemented in cmakev2 yet.')
+def test_target_guessing()
+```
+
 ### Build snapshots
 
 `get_snapshot(list_of_globs)` function takes a list of glob expressions, finds the files matching these expressions, and returns a `Snapshot` instance. `Snapshot` instances record file names and their modification timestamps. Two `Snapshot` instances can be compared using `assert_same` and `assert_different` methods:

tools/test_build_system/conftest.py

@@ -10,7 +10,10 @@ from pathlib import Path
 from tempfile import mkdtemp
 
 import pytest
+from _pytest.config import Config
 from _pytest.fixtures import FixtureRequest
+from _pytest.main import Session
+from _pytest.nodes import Item
 from test_build_system_helpers import EXT_IDF_PATH
 from test_build_system_helpers import EnvDict
 from test_build_system_helpers import IdfPyFunc
@@ -235,3 +238,13 @@ def idf_py(default_idf_env: EnvDict) -> IdfPyFunc:
         return run_idf_py(*args, env=default_idf_env, workdir=os.getcwd(), check=check, input_str=input_str)  # type: ignore
 
     return result
+
+
+def pytest_collection_modifyitems(session: Session, config: Config, items: list[Item]) -> None:
+    if not config.getoption('--buildv2', False):
+        return
+    for item in items:
+        marker = item.get_closest_marker('buildv2_skip')
+        if marker:
+            reason = marker.args[0] if marker.args else 'Skipped as this test is specific to build system v1.'
+            item.add_marker(pytest.mark.skip(reason=reason))

tools/test_build_system/pytest.ini

@@ -21,3 +21,4 @@ markers =
     idf_copy_with_space: ensures that destination directory where IDF is copied contain space
     force_temp_work_dir: force temporary folder as the working directory
     with_idf_components: automatically create/delete components under IDF_PATH
+    buildv2_skip: mark the test to run only when the --buildv2 command line option is not used