FIX: Use a more robust strategy for detecting ANTs version

nipype/interfaces/ants/base.py

@@ -3,9 +3,10 @@
 # vi: set ft=python sts=4 ts=4 sw=4 et:
 """The ants module provides basic functions for interfacing with ANTS tools."""
 import os
+from packaging.version import Version, parse
 
 # Local imports
-from ... import logging, LooseVersion
+from ... import logging
 from ..base import CommandLine, CommandLineInputSpec, traits, isdefined, PackageInfo
 
 iflogger = logging.getLogger("nipype.interface")
@@ -43,13 +44,16 @@ def parse_version(raw_info):
         # -githash may or may not be appended
         v_string = v_string.split("-")[0]
 
-        # 2.2.0-equivalent version string
-        if "post" in v_string and LooseVersion(v_string) >= LooseVersion(
-            "2.1.0.post789"
-        ):
-            return "2.2.0"
-        else:
-            return ".".join(v_string.split(".")[:3])
+        version = parse(v_string)
+
+        # Known mislabeled versions
+        if version.is_postrelease:
+            if version.base_version == "2.1.0" and version.post >= 789:
+                return "2.2.0"
+
+        # Unless we know of a specific reason to re-version, we will
+        # treat the base version (before pre/post/dev) as authoritative
+        return version.base_version
 
 
 class ANTSCommandInputSpec(CommandLineInputSpec):

nipype/interfaces/ants/tests/test_base.py

@@ -0,0 +1,25 @@
+from nipype.interfaces.ants.base import Info
+
+import pytest
+
+# fmt: off
+ANTS_VERSIONS = [("""\
+ANTs Version: 2.3.3.dev168-g29bdf
+Compiled: Jun  9 2020 03:44:55
+
+""", "2.3.3"), ("""\
+ANTs Version: v2.3.5.post76-g28dd25c
+Compiled: Nov 16 2021 14:57:48
+
+""", "2.3.5"), ("""\
+ANTs Version: v2.1.0.post789-g0740f
+Compiled: I don't still have this so not going to pretend
+
+""", "2.2.0"),
+]
+# fmt: on
+
+
+@pytest.mark.parametrize("raw_info, version", ANTS_VERSIONS)
+def test_version_parser(raw_info, version):
+    assert Info.parse_version(raw_info) == version