use setuptools_scm to generate a version file

This avoids the overhead of using importlib.metadata to search for the
version.

Signed-off-by: Jan Luebbe <jlu@pengutronix.de>

Author: jluebbe

.gitignore

@@ -17,6 +17,7 @@
 /dist
 /.pytest_cache/
 /htmlcov/
+/labgrid/_version.py
 /dockerfiles/staging/crossbar/*
 !/dockerfiles/staging/crossbar/places_example.yaml
 /.idea

labgrid/__init__.py

@@ -6,3 +6,8 @@
 from .step import step, steps
 from .stepreporter import StepReporter
 from .consoleloggingreporter import ConsoleLoggingReporter
+
+try:
+    from ._version import __version__
+except ImportError:
+    __version__ = "unknown"

labgrid/util/version.py

@@ -4,6 +4,12 @@
 
 
 def labgrid_version():
+    try:
+        from .._version import __version__
+        return __version__
+    except ModuleNotFoundError:
+        pass
+
     import contextlib
     from importlib.metadata import PackageNotFoundError, version
 

pyproject.toml

@@ -153,6 +153,7 @@ packages = [
 
 [tool.setuptools_scm]
 local_scheme = "no-local-version"
+version_file = "labgrid/_version.py"
 
 [tool.pytest.ini_options]
 testpaths = [