Improve _is_backport

tagbot/action/changelog.py

@@ -67,27 +67,26 @@ def _previous_release(self, version_tag: str) -> Optional[GitRelease]:
                 prev_ver = ver
         return prev_rel
 
+    VERSION_PATTERN = re.compile(r"^(.*?)[-v]?(\d+\.\d+\.\d+(?:\.\d+)*)(?:[-+].+)?$")
+
     def _is_backport(self, version: str) -> bool:
         """Determine whether or not the version is a backport."""
         try:
-            # Regular expression to match version tags with or without prefix
-            version_pattern = re.compile(r"^(.*[-v]?)(\d+\.\d+\.\d+)$")
-
             # Extract the version number from the input
-            match = version_pattern.match(version)
+            match = VERSION_PATTERN.match(version)
             if not match:
-                raise ValueError("Invalid version format: ${version}")
+                raise ValueError(f"Invalid version format: {version}")
 
-            # Extract the base version without the 'v' prefix
+            package_name = match.group(1)
             cur_ver = VersionInfo.parse(match.group(2))
-            package_name = match.group(1).strip("-v")
 
             for r in self._repo._repo.get_releases():
-                tag_match = version_pattern.match(r.tag_name)
+                tag_match = VERSION_PATTERN.match(r.tag_name)
                 if not tag_match:
                     continue
 
-                tag_package_name = tag_match.group(1).strip("-v")
+                tag_package_name = tag_match.group(1)
+
                 if tag_package_name != package_name:
                     continue
 
@@ -107,7 +106,9 @@ def _is_backport(self, version: str) -> bool:
             return False
         except Exception as e:
             # This is a best-effort function so we don't fail the entire process
-            logger.error(f"Checking if backport failed. Assuming False: {e}")
+            logger.error(
+                f"Checking if backport failed for version {version}. Assuming False: {e}"
+            )
             return False
 
     def _issues_and_pulls(