refactor: remove semver class consolidate version parsing

This PR removes all of the custom version parsing functions where we try
to make sense about the version (e.g. extracting major/minor versions).

Author: aignas

python/private/BUILD.bazel

@@ -139,7 +139,7 @@ bzl_library(
     name = "config_settings_bzl",
     srcs = ["config_settings.bzl"],
     deps = [
-        ":semver_bzl",
+        ":version_bzl",
         "@bazel_skylib//lib:selects",
         "@bazel_skylib//rules:common_settings",
     ],

python/private/config_settings.bzl

@@ -18,7 +18,7 @@
 load("@bazel_skylib//lib:selects.bzl", "selects")
 load("@bazel_skylib//rules:common_settings.bzl", "BuildSettingInfo")
 load("//python/private:text_util.bzl", "render")
-load(":semver.bzl", "semver")
+load(":version.bzl", "version")
 
 _PYTHON_VERSION_FLAG = Label("//python/config_settings:python_version")
 _PYTHON_VERSION_MAJOR_MINOR_FLAG = Label("//python/config_settings:python_version_major_minor")
@@ -154,8 +154,8 @@ _python_version_flag = rule(
 def _python_version_major_minor_flag_impl(ctx):
     input = _flag_value(ctx.attr._python_version_flag)
     if input:
-        version = semver(input)
-        value = "{}.{}".format(version.major, version.minor)
+        v = version.parse(input, strict=True)
+        value = "{}.{}".format(v.release[0], v.release[1])
     else:
         value = ""
 

python/private/hermetic_runtime_repo_setup.bzl

@@ -20,7 +20,7 @@ load("//python:py_runtime_pair.bzl", "py_runtime_pair")
 load("//python/cc:py_cc_toolchain.bzl", "py_cc_toolchain")
 load(":glob_excludes.bzl", "glob_excludes")
 load(":py_exec_tools_toolchain.bzl", "py_exec_tools_toolchain")
-load(":semver.bzl", "semver")
+load(":version.bzl", "version")
 
 _IS_FREETHREADED = Label("//python/config_settings:is_py_freethreaded")
 
@@ -53,8 +53,11 @@ def define_hermetic_runtime_toolchain_impl(
             use.
     """
     _ = name  # @unused
-    version_info = semver(python_version)
-    version_dict = version_info.to_dict()
+    version_info = version.parse(python_version, strict = True)
+    version_dict = {
+        "major": version_info.release[0],
+        "minor": version_info.release[1],
+    }
     native.filegroup(
         name = "files",
         srcs = native.glob(
@@ -198,9 +201,10 @@ def define_hermetic_runtime_toolchain_impl(
         files = [":files"],
         interpreter = python_bin,
         interpreter_version_info = {
-            "major": str(version_info.major),
-            "micro": str(version_info.patch),
-            "minor": str(version_info.minor),
+            # TODO @aignas 2025-05-13: we can add even more things here
+            "major": str(version_info.release[0]),
+            "micro": str(version_info.release[1]),
+            "minor": str(version_info.release[2]),
         },
         coverage_tool = select({
             # Convert empty string to None

python/private/pypi/extension.bzl

@@ -21,7 +21,7 @@ load("//python/private:auth.bzl", "AUTH_ATTRS")
 load("//python/private:full_version.bzl", "full_version")
 load("//python/private:normalize_name.bzl", "normalize_name")
 load("//python/private:repo_utils.bzl", "repo_utils")
-load("//python/private:semver.bzl", "semver")
+load("//python/private:version.bzl", "version")
 load("//python/private:version_label.bzl", "version_label")
 load(":attrs.bzl", "use_isolated")
 load(":evaluate_markers.bzl", "evaluate_markers_py", EVALUATE_MARKERS_SRCS = "SRCS")
@@ -35,9 +35,9 @@ load(":whl_config_setting.bzl", "whl_config_setting")
 load(":whl_library.bzl", "whl_library")
 load(":whl_repo_name.bzl", "pypi_repo_name", "whl_repo_name")
 
-def _major_minor_version(version):
-    version = semver(version)
-    return "{}.{}".format(version.major, version.minor)
+def _major_minor_version(v):
+    v = version.parse(v)
+    return "{}.{}".format(v.release[0], v.release[1])
 
 def _whl_mods_impl(whl_mods_dict):
     """Implementation of the pip.whl_mods tag class.

python/private/python.bzl

@@ -21,7 +21,7 @@ load(":full_version.bzl", "full_version")
 load(":python_register_toolchains.bzl", "python_register_toolchains")
 load(":pythons_hub.bzl", "hub_repo")
 load(":repo_utils.bzl", "repo_utils")
-load(":semver.bzl", "semver")
+load(":version.bzl", "version")
 load(":text_util.bzl", "render")
 load(":toolchains_repo.bzl", "multi_toolchain_aliases")
 load(":util.bzl", "IS_BAZEL_6_4_OR_HIGHER")
@@ -413,9 +413,9 @@ def _fail_multiple_default_toolchains(first, second):
     ))
 
 def _validate_version(*, version, _fail = fail):
-    parsed = semver(version)
-    if parsed.patch == None or parsed.build or parsed.pre_release:
-        _fail("The 'python_version' attribute needs to specify an 'X.Y.Z' semver-compatible version, got: '{}'".format(version))
+    parsed = version.parse(version, strict = True)
+    if len(parsed.release) != 3 or parsed.pre or parsed.local or parsed.post:
+        _fail("The 'python_version' attribute needs to specify an 'X.Y.Z' semver-compatible version, got: '{}'".format(parsed.string))
         return False
 
     return True
@@ -512,11 +512,11 @@ def _process_global_overrides(*, tag, default, _fail = fail):
 
     if tag.minor_mapping:
         for minor_version, full_version in tag.minor_mapping.items():
-            parsed = semver(minor_version)
-            if parsed.patch != None or parsed.build or parsed.pre_release:
+            parsed = version.parse(minor_version, strict = True)
+            if len(parsed.release) != 2 or parsed.pre or parsed.local or parsed.post:
                 fail("Expected the key to be of `X.Y` format but got `{}`".format(minor_version))
-            parsed = semver(full_version)
-            if parsed.patch == None:
+            parsed = version.parse(full_version, strict = True)
+            if len(parsed.release) != 3 or parsed.pre or parsed.local or parsed.post:
                 fail("Expected the value to at least be of `X.Y.Z` format but got `{}`".format(minor_version))
 
         default["minor_mapping"] = tag.minor_mapping
@@ -605,8 +605,8 @@ def _get_toolchain_config(*, modules, _fail = fail):
 
     versions = {}
     for version_string in available_versions:
-        v = semver(version_string)
-        versions.setdefault("{}.{}".format(v.major, v.minor), []).append((int(v.patch), version_string))
+        v = version.parse(version_string, strict = True)
+        versions.setdefault("{}.{}".format(v.release[0], v.release[1]), []).append((v.release[2], version_string))
 
     minor_mapping = {
         major_minor: max(subset)[1]

python/private/semver.bzl

@@ -781,7 +781,7 @@ def _test_single_version_platform_override_errors(env):
             overrides = [
                 _single_version_platform_override(python_version = "3.12", platform = "foo"),
             ],
-            want_error = "The 'python_version' attribute needs to specify an 'X.Y.Z' semver-compatible version, got: '3.12'",
+            want_error = "The 'python_version' attribute needs to conform to PEP440 versions, got: '3.12'",
         ),
         struct(
             overrides = [