Replace pkg_resources usage with packaging + importlib.metadata (#392)

geoalchemy2/__init__.py

@@ -443,12 +443,25 @@ def load_spatialite(dbapi_conn, connection_record):
 
 # Get version number
 __version__ = "UNKNOWN VERSION"
+
+# Attempt to use importlib.metadata first because it's much faster
+# though it's only available in Python 3.8+ so we'll need to fall
+# back to pkg_resources for Python 3.7 support
 try:
-    from pkg_resources import DistributionNotFound
-    from pkg_resources import get_distribution
+    import importlib.metadata
+except ImportError:
+    try:
+        from pkg_resources import DistributionNotFound
+        from pkg_resources import get_distribution
+    except ImportError:  # pragma: no cover
+        pass
+    else:
+        try:
+            __version__ = get_distribution('GeoAlchemy2').version
+        except DistributionNotFound:  # pragma: no cover
+            pass
+else:
     try:
-        __version__ = get_distribution('GeoAlchemy2').version
-    except DistributionNotFound:  # pragma: no cover
-        pass  # pragma: no cover
-except ImportError:  # pragma: no cover
-    pass  # pragma: no cover
+        __version__ = importlib.metadata.version('GeoAlchemy2')
+    except importlib.metadata.PackageNotFoundError:  # pragma: no cover
+        pass

geoalchemy2/shape.py

@@ -8,12 +8,12 @@
 """
 import shapely.wkb
 import shapely.wkt
-from pkg_resources import parse_version
+from packaging import version
 
 from .elements import WKBElement
 from .elements import WKTElement
 
-if parse_version(shapely.__version__) < parse_version("1.7"):  # pragma: no cover
+if version.parse(shapely.__version__) < version.parse('1.7'):  # pragma: no cover
     ######################################################################
     # Backport function from Shapely 1.7
     from shapely.geometry.base import geom_factory

setup.cfg

@@ -23,7 +23,7 @@ passenv=
 setenv=
     COVERAGE_FILE = {env:COVERAGE_FILE:.coverage-{envname}}
     EXPECTED_COV = 91
-    pypy3: EXPECTED_COV = 78
+    pypy3: EXPECTED_COV = 77
 deps=
     alembic
     sqla14: SQLAlchemy==1.4.*