More robust version check test (#3965)

* More robust version number handling.

* Fix typo in docstring.

* Refinements.

Author: jhale

python/dolfinx/__init__.py

@@ -45,9 +45,9 @@
     ufcx_signature,
 )
 
-from importlib.metadata import metadata
+from importlib.metadata import version
 
-__version__ = metadata("fenics-dolfinx")["Version"]
+__version__ = version("fenics-dolfinx")
 
 _cpp.common.init_logging(sys.argv)
 del _cpp, sys

python/pyproject.toml

@@ -45,7 +45,7 @@ docs = [
 lint = ["ruff>=0.2.0"]
 optional = ["numba", "pyamg"]
 petsc4py = ["petsc4py"]
-test = ["matplotlib", "networkx", "pytest", "scipy", "fenics-dolfinx[optional]"]
+test = ["matplotlib", "networkx", "packaging", "pytest", "scipy", "fenics-dolfinx[optional]"]
 ci = [
       "mypy",
       "pytest-xdist",

python/test/unit/common/test_version.py

@@ -4,16 +4,27 @@
 #
 # SPDX-License-Identifier:    LGPL-3.0-or-later
 
+from packaging.version import parse
 
 import dolfinx
 
 
 def test_version():
-    """Test that installed Python version matches C++ version."""
-    # Change any final '.dev0' to '.0'
-    py_version = dolfinx.__version__.replace("dev0", "0")
-    cpp_version = dolfinx.cpp.__version__
-    if py_version != cpp_version:
-        raise RuntimeError(
-            f"Incorrect versions. Python version: {py_version}, Core version: {cpp_version}"
-        )
+    """Test that installed Python version matches C++ version.
+
+    Python DOLFINx follows `major.minor.micro` with the append of `.devx`
+    and `.postx` denoting development and postrelease, respectively.
+
+    C++ DOLFINx follows `major.minor.micro` with a development denoted
+    `major.minor.micro.0`. postrelease cannot be reflected in C++,
+    any changes to the C++ code should bump micro.
+    """
+    cpp_version = parse(dolfinx.cpp.__version__)
+    python_version = parse(dolfinx.__version__)
+
+    assert cpp_version.major == python_version.major
+    assert cpp_version.minor == python_version.minor
+    assert cpp_version.micro == python_version.micro
+
+    cpp_is_devrelease = True if len(cpp_version.release) == 4 else False
+    assert cpp_is_devrelease == python_version.is_devrelease