#432 Use importlib.metadata.version to get the version

pyproject.toml

@@ -31,6 +31,7 @@ requires-python = ">=3.8"
 dependencies = [
     "click",
     "importlib-resources>=5; python_version<'3.10'",
+    "importlib-metadata==4.6.*; python_version<'3.10'",
     "incremental",
     "jinja2",
     "tomli; python_version<'3.11'",

src/towncrier/_project.py

@@ -5,17 +5,24 @@
 Responsible for getting the version and name from a project.
 """
 
-
 from __future__ import annotations
 
 import sys
 
 from importlib import import_module
+from importlib.metadata import PackageNotFoundError
+from importlib.metadata import version as metadata_version
 from types import ModuleType
 
 from incremental import Version as IncrementalVersion
 
 
+try:
+    from importlib.metadata import packages_distributions
+except ImportError:
+    from importlib_metadata import packages_distributions
+
+
 def _get_package(package_dir: str, package: str) -> ModuleType:
     try:
         module = import_module(package)
@@ -37,13 +44,31 @@ def _get_package(package_dir: str, package: str) -> ModuleType:
     return module
 
 
+def _get_metadata_version(package: str) -> str | None:
+    distributions = packages_distributions()
+    distribution_names = distributions.get(package)
+    if not distribution_names or not len(distribution_names) == 1:
+        # We can only determine the version if there is exactly one matching distribution.
+        return None
+    try:
+        return metadata_version(distribution_names[0])
+    except PackageNotFoundError:
+        return None
+
+
 def get_version(package_dir: str, package: str) -> str:
+    # First try to get the version from the package metadata.
+    if version := _get_metadata_version(package):
+        return version
+
     module = _get_package(package_dir, package)
 
     version = getattr(module, "__version__", None)
 
     if not version:
-        raise Exception("No __version__, I don't know how else to look")
+        raise Exception(
+            f"No __version__ or metadata version info for the {package} package."
+        )
 
     if isinstance(version, str):
         return version.strip()