fix(version_schemes): support arbitrary semver pre-release labels

Extend BaseVersion with a custom _VERSION_PATTERN regex that accepts
arbitrary pre-release identifiers (e.g., -release, -SNAPSHOT,
-reallyweird) instead of only PEP 440's alpha/beta/rc.

This fixes InvalidVersion errors when using tags like v0.7.1-release
or v0.0.1-SNAPSHOT with commitizen's changelog and bump commands.

Closes #950

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: bearomorphism

commitizen/version_schemes.py

@@ -145,11 +145,57 @@ def bump(
 VersionScheme: TypeAlias = type[VersionProtocol]
 
 
+# Custom version pattern that extends packaging's PEP 440 regex to support
+# arbitrary semver pre-release labels (e.g., -release, -SNAPSHOT, -reallyweird).
+# Python's packaging library does not use semver; it predates it. We cannot fully
+# rely on packaging.version for semver-compatible parsing.
+# See: https://github.com/pypa/packaging/blob/14b83e15dbb9caa87c63646ba7808b2b5e460ce6/src/packaging/version.py#L117
+_VERSION_PATTERN = r"""^\s*
+    v?
+    (?:
+        (?:(?P<epoch>[0-9]+)!)?                           # epoch
+        (?P<release>[0-9]+(?:\.[0-9]+)*)                  # release segment
+        (?P<pre>                                          # pre-release
+            [-_\.]?
+            (?P<pre_l>
+                (?!                                       # negative lookahead to prevent
+                    [-_\.]?                               # matching post, rev, r, dev
+                    (post|rev|r|dev)
+                    [-_\.]?
+                    ([0-9]+)?
+                $)
+                [a-z]+?                                   # match any letters (semver support)
+            )
+            [-_\.]?
+            (?P<pre_n>[0-9]+)?
+        )?
+        (?P<post>                                         # post release
+            (?:-(?P<post_n1>[0-9]+))
+            |
+            (?:
+                [-_\.]?
+                (?P<post_l>post|rev|r)
+                [-_\.]?
+                (?P<post_n2>[0-9]+)?
+            )
+        )?
+        (?P<dev>                                          # dev release
+            [-_\.]?
+            (?P<dev_l>dev)
+            [-_\.]?
+            (?P<dev_n>[0-9]+)?
+        )?
+    )
+    (?:\+(?P<local>[a-z0-9]+(?:[-_\.][a-z0-9]+)*))?       # local version
+\s*$"""
+
+
 class BaseVersion(_BaseVersion):
     """
     A base class implementing the `VersionProtocol` for PEP440-like versions.
     """
 
+    _regex: re.Pattern = re.compile(_VERSION_PATTERN, re.VERBOSE | re.IGNORECASE)
     parser: ClassVar[re.Pattern] = _DEFAULT_VERSION_PARSER
     """Regex capturing this version scheme into a `version` group"""
 

tests/test_version_scheme_semver.py

@@ -250,6 +250,37 @@
             ),
             "1.0.0",
         ),
+        # arbitrary semver pre-release labels (issue #950)
+        (
+            VersionSchemeTestArgs(
+                current_version="1.0.0-reallyweird",
+                increment="PATCH",
+                prerelease="reallyweird",
+                prerelease_offset=0,
+                devrelease=None,
+            ),
+            "1.0.0-reallyweird1",
+        ),
+        (
+            VersionSchemeTestArgs(
+                current_version="v0.7.1-release",
+                increment="PATCH",
+                prerelease="release",
+                prerelease_offset=0,
+                devrelease=None,
+            ),
+            "0.7.1-release1",
+        ),
+        (
+            VersionSchemeTestArgs(
+                current_version="v0.0.1-SNAPSHOT",
+                increment="PATCH",
+                prerelease="SNAPSHOT",
+                prerelease_offset=0,
+                devrelease=None,
+            ),
+            "0.0.1-snapshot1",
+        ),
         # simple flow
         (
             VersionSchemeTestArgs(

tests/test_version_scheme_semver2.py

@@ -240,6 +240,17 @@
             ),
             "1.0.0",
         ),
+        # arbitrary semver pre-release labels (issue #950)
+        (
+            VersionSchemeTestArgs(
+                current_version="1.0.0-reallyweird",
+                increment="PATCH",
+                prerelease="reallyweird",
+                prerelease_offset=0,
+                devrelease=None,
+            ),
+            "1.0.0-reallyweird.1",
+        ),
         # simple_flow
         (
             VersionSchemeTestArgs(