fix: prefer X.Y over X.Y.Z version aliases in python.toolchain

examples/bzlmod/MODULE.bazel

@@ -28,7 +28,8 @@ python.toolchain(
 # work in progress.
 python.toolchain(
     configure_coverage_tool = True,
-    python_version = "3.10",
+    # One can also provide the full Python version.
+    python_version = "3.10.9",
 )
 
 # You only need to load this repositories if you are using multiple Python versions.
@@ -102,7 +103,10 @@ pip.parse(
 )
 pip.parse(
     hub_name = "pip",
-    python_version = "3.10",
+    # NOTE: if you are registering the python toolchain with the full version
+    # in 'python.toolchain' call, then you need to use the full version here as
+    # well or otherwise the resolution will fail.
+    python_version = "3.10.9",
     requirements_lock = "//:requirements_lock_3_10.txt",
     requirements_windows = "//:requirements_windows_3_10.txt",
     # These modifications were created above and we

examples/bzlmod/libs/my_lib/__init__.py

@@ -19,4 +19,9 @@ def websockets_is_for_python_version(sanitized_version_check):
     # We are checking that the name of the repository folders
     # match the expexted generated names. If we update the folder
     # structure or naming we will need to modify this test
-    return f"pip_{sanitized_version_check}_websockets" in websockets.__file__
+    if f"pip_{sanitized_version_check}_websockets" in websockets.__file__:
+        return True
+
+    raise RuntimeError(
+        f"Expected version '{sanitized_version_check}' was not in {websockets.__file__}"
+    )

examples/bzlmod/other_module/MODULE.bazel

@@ -27,7 +27,7 @@ PYTHON_NAME_311 = "python_3_11"
 python = use_extension("@rules_python//python/extensions:python.bzl", "python")
 python.toolchain(
     configure_coverage_tool = True,
-    python_version = "3.9",
+    python_version = "3.9.10",
 )
 python.toolchain(
     configure_coverage_tool = True,

examples/bzlmod/tests/my_lib_test.py

@@ -21,6 +21,10 @@
 # If we update the folder structure or naming we need to modify this test.
 sanitized_version_check = f"{sys.version_info.major}{sys.version_info.minor}"
 
-if not my_lib.websockets_is_for_python_version(sanitized_version_check):
-    print("expected package for Python version is different than returned")
-    sys.exit(1)
+try:
+    my_lib.websockets_is_for_python_version(sanitized_version_check)
+except RuntimeError as e:
+    print(
+        f"Expected package for Python version is different than returned. Current version is {sys.version_info}"
+    )
+    raise e

examples/multi_python_versions/WORKSPACE

@@ -22,7 +22,7 @@ python_register_multi_toolchains(
         "3.8",
         "3.9",
         "3.10",
-        "3.11",
+        "3.11.1",
     ],
     register_coverage_tool = True,
 )
@@ -38,13 +38,13 @@ multi_pip_parse(
     default_version = default_python_version,
     python_interpreter_target = {
         "3.10": interpreter_3_10,
-        "3.11": interpreter_3_11,
+        "3.11.1": interpreter_3_11,
         "3.8": interpreter_3_8,
         "3.9": interpreter_3_9,
     },
     requirements_lock = {
         "3.10": "//requirements:requirements_lock_3_10.txt",
-        "3.11": "//requirements:requirements_lock_3_11.txt",
+        "3.11.1": "//requirements:requirements_lock_3_11.txt",
         "3.8": "//requirements:requirements_lock_3_8.txt",
         "3.9": "//requirements:requirements_lock_3_9.txt",
     },

examples/multi_python_versions/libs/my_lib/__init__.py

@@ -16,4 +16,12 @@
 
 
 def websockets_is_for_python_version(sanitized_version_check):
-    return f"pypi_{sanitized_version_check}_websockets" in websockets.__file__
+    # We are checking that the name of the repository folders
+    # match the expexted generated names. If we update the folder
+    # structure or naming we will need to modify this test
+    if f"pypi_{sanitized_version_check}_websockets" in websockets.__file__:
+        return True
+
+    raise RuntimeError(
+        f"Expected version '{sanitized_version_check}' was not in {websockets.__file__}"
+    )

python/extensions/python.bzl

@@ -16,6 +16,7 @@
 
 load("//python:repositories.bzl", "python_register_toolchains")
 load("//python/extensions/private:pythons_hub.bzl", "hub_repo")
+load("//python/private:full_version.bzl", "full_version")
 load("//python/private:toolchains_repo.bzl", "multi_toolchain_aliases")
 
 # This limit can be increased essentially arbitrarily, but doing so will cause a rebuild of all
@@ -74,7 +75,7 @@ def _python_impl(module_ctx):
         module_toolchain_versions = []
 
         for toolchain_attr in mod.tags.toolchain:
-            toolchain_version = toolchain_attr.python_version
+            toolchain_version, _, _ = full_version(toolchain_attr.python_version).rpartition(".")
             toolchain_name = "python_" + toolchain_version.replace(".", "_")
 
             # Duplicate versions within a module indicate a misconfigured module.

python/pip.bzl

@@ -19,6 +19,7 @@ load("//python/pip_install:requirements.bzl", _compile_pip_requirements = "compi
 load("//python/private:bzlmod_enabled.bzl", "BZLMOD_ENABLED")
 load("//python/private:full_version.bzl", "full_version")
 load("//python/private:render_pkg_aliases.bzl", "NO_MATCH_ERROR_MESSAGE_TEMPLATE")
+load("//python/private:version_label.bzl", "version_label")
 
 compile_pip_requirements = _compile_pip_requirements
 package_annotation = _package_annotation
@@ -369,7 +370,7 @@ def multi_pip_parse(name, default_version, python_versions, python_interpreter_t
         if not python_version in requirements_lock:
             fail("Missing requirements_lock for Python version %s in '%s'" % (python_version, name))
 
-        pip_parse_name = name + "_" + python_version.replace(".", "_")
+        pip_parse_name = name + "_" + version_label(full_version(python_version), sep = "_")
         pip_parse(
             name = pip_parse_name,
             python_interpreter_target = python_interpreter_target[python_version],

python/private/toolchains_repo.bzl

@@ -30,6 +30,7 @@ load(
     "PLATFORMS",
     "WINDOWS_NAME",
 )
+load(":full_version.bzl", "full_version")
 load(":which.bzl", "which_with_fail")
 
 def get_repository_name(repository_workspace):
@@ -252,8 +253,12 @@ def _multi_toolchain_aliases_impl(rctx):
     rules_python = rctx.attr._rules_python_workspace.workspace_name
 
     for python_version, repository_name in rctx.attr.python_versions.items():
-        file = "{}/defs.bzl".format(python_version)
-        rctx.file(file, content = """\
+        python_version = full_version(python_version)
+        for is_short in [False, True]:
+            python_version_short, _, _ = python_version.rpartition(".")
+            v = python_version_short if is_short else python_version
+
+            rctx.file("{}/defs.bzl".format(v), content = """\
 # Generated by python/private/toolchains_repo.bzl
 
 load(
@@ -266,16 +271,18 @@ load(
     _py_test = "py_test",
 )
 
+{warning}
 compile_pip_requirements = _compile_pip_requirements
 host_platform = _host_platform
 interpreter = _interpreter
 py_binary = _py_binary
 py_console_script_binary = _py_console_script_binary
 py_test = _py_test
 """.format(
-            repository_name = repository_name,
-        ))
-        rctx.file("{}/BUILD.bazel".format(python_version), "")
+                repository_name = repository_name,
+                warning = "" if is_short else 'print("switch to importing from \"{}:defs.bzl\"")'.format(python_version_short),
+            ))
+            rctx.file("{}/BUILD.bazel".format(v), "")
 
     pip_bzl = """\
 # Generated by python/private/toolchains_repo.bzl