Add pyproject_toml to pip.parse; revert extension_metadata root deps

Author: golithe

python/private/pypi/extension.bzl

@@ -367,9 +367,14 @@ You cannot use both the additive_build_content and additive_build_content_file a
 
     for mod in module_ctx.modules:
         for pip_attr in mod.tags.parse:
-            python_version = pip_attr.python_version or config.python_version
+            python_version = pip_attr.python_version
+            if not python_version and pip_attr.pyproject_toml:
+                pyproject = read_pyproject(module_ctx, pip_attr.pyproject_toml)
+                if pyproject.requires_python:
+                    python_version = version_from_requires_python(pyproject.requires_python)
+            python_version = python_version or config.python_version
             if not python_version:
-                _fail("pip.parse() requires either python_version attribute or pip.default(pyproject_toml=...) to be set")
+                _fail("pip.parse() requires one of `python_version`, `pyproject_toml`, or `pip.default(pyproject_toml=...)` to be set")
 
             hub_name = pip_attr.hub_name
             if hub_name == "pypi":
@@ -722,8 +727,10 @@ When specified, reads the `requires-python` field from pyproject.toml and uses
 it as the default python_version for all `pip.parse()` calls that don't
 explicitly specify one.
 
+:::{note}
 The version must be specified as `==X.Y.Z` (exact version with full semver).
 This is designed to work with dependency management tools like Renovate.
+:::
 
 :::{versionadded} VERSION_NEXT_FEATURE
 :::
@@ -897,6 +904,21 @@ find in case extra indexes are specified.
 """,
             default = True,
         ),
+        "pyproject_toml": attr.label(
+            mandatory = False,
+            doc = """\
+Label pointing to a pyproject.toml file to read the Python version from.
+When specified, the `requires-python` field is used as the `python_version`
+for this `pip.parse()` call, unless `python_version` is set explicitly.
+
+:::{note}
+The version must be specified as `==X.Y.Z` (exact version with full semver).
+:::
+
+:::{versionadded} VERSION_NEXT_FEATURE
+:::
+""",
+        ),
         "python_version": attr.string(
             mandatory = False,
             doc = """
@@ -910,6 +932,11 @@ a corresponding `python.toolchain()` configured.
 :::{seealso}
 The {obj}`pyproject_toml` attribute for getting the version from a project file.
 :::
+
+:::{versionchanged} VERSION_NEXT_FEATURE
+No longer mandatory if the {obj}`pyproject_toml` attribute or
+{obj}`pip.default.pyproject_toml` is specified.
+:::
 """,
         ),
         "simpleapi_skip": attr.string_list(

python/private/pyproject_utils.bzl

@@ -38,6 +38,9 @@ def version_from_requires_python(requires_python):
     Returns:
         {type}`str` the normalized version string (e.g. `"3.13.9"`).
     """
+    if not requires_python:
+        fail("`requires-python` must be specified")
+
     if not requires_python.startswith("=="):
         fail("`requires-python` must pin an exact version with `==`, got: {}".format(requires_python))
 

python/private/python.bzl

@@ -465,14 +465,7 @@ def _python_impl(module_ctx):
         )
 
     if bazel_features.external_deps.extension_metadata_has_reproducible:
-        # Build the list of direct dependencies
-        root_direct_deps = ["pythons_hub", "python_versions"]
-
-        return module_ctx.extension_metadata(
-            root_module_direct_deps = root_direct_deps,
-            root_module_direct_dev_deps = [],
-            reproducible = True,
-        )
+        return module_ctx.extension_metadata(reproducible = True)
     else:
         return None
 

tests/pypi/extension/extension_tests.bzl

@@ -24,7 +24,7 @@ load(":pip_parse.bzl", _parse = "pip_parse")
 
 _tests = []
 
-def _pypi_mock_mctx(*modules, os_name = "unittest", arch_name = "exotic", environ = {}, read = None):
+def _pypi_mock_mctx(*modules, os_name = "unittest", arch_name = "exotic", environ = {}, read = None, mock_files = {}):
     _ = read  # @unused
     return mocks.mctx(
         modules = list(modules),
@@ -36,7 +36,7 @@ def _pypi_mock_mctx(*modules, os_name = "unittest", arch_name = "exotic", enviro
 simple==0.0.1 \
     --hash=sha256:deadbeef \
     --hash=sha256:deadbaaf""",
-        },
+        } | mock_files,
     )
 
 def _default(
@@ -177,6 +177,58 @@ def _test_simple(env):
 
 _tests.append(_test_simple)
 
+def _test_pip_parse_pyproject_toml(env):
+    # pip.parse() reads the version from pyproject.toml's requires-python when
+    # python_version is not set explicitly.
+    pypi = _parse_modules(
+        env,
+        module_ctx = _pypi_mock_mctx(
+            _mod(
+                name = "rules_python",
+                parse = [
+                    _parse(
+                        hub_name = "pypi",
+                        pyproject_toml = "pyproject.toml",
+                        simpleapi_skip = ["simple"],
+                        requirements_lock = "requirements.txt",
+                    ),
+                ],
+            ),
+            os_name = "linux",
+            arch_name = "x86_64",
+            mock_files = {
+                "pyproject.toml": "[project]\nrequires-python = \"==3.15.19\"\n",
+            },
+        ),
+        available_interpreters = {
+            "python_3_15_19_host": "unit_test_interpreter_target",
+        },
+        minor_mapping = {"3.15": "3.15.19"},
+    )
+
+    # Resolves identically to passing python_version = "3.15.19" explicitly:
+    # the full version drives interpreter selection, hub naming uses major.minor.
+    pypi.exposed_packages().contains_exactly({"pypi": ["simple"]})
+    pypi.hub_whl_map().contains_exactly({"pypi": {
+        "simple": {
+            "pypi_315_simple": [
+                whl_config_setting(
+                    version = "3.15",
+                ),
+            ],
+        },
+    }})
+    pypi.whl_libraries().contains_exactly({
+        "pypi_315_simple": {
+            "config_load": "@pypi//:config.bzl",
+            "dep_template": "@pypi//{name}:{target}",
+            "python_interpreter_target": "unit_test_interpreter_target",
+            "requirement": "simple==0.0.1 --hash=sha256:deadbeef --hash=sha256:deadbaaf",
+        },
+    })
+
+_tests.append(_test_pip_parse_pyproject_toml)
+
 def _test_simple_isolated(env):
     """Simulate `isolate = True` with parse_modules.
 

tests/pypi/extension/pip_parse.bzl

@@ -3,7 +3,7 @@
 def pip_parse(
         *,
         hub_name,
-        python_version,
+        python_version = None,
         add_libdir_to_library_search_path = False,
         auth_patterns = {},
         download_only = False,
@@ -19,6 +19,7 @@ def pip_parse(
         netrc = None,
         parse_all_requirements_files = True,
         pip_data_exclude = None,
+        pyproject_toml = None,
         python_interpreter = None,
         python_interpreter_target = None,
         quiet = True,
@@ -52,6 +53,7 @@ def pip_parse(
         netrc = netrc,
         parse_all_requirements_files = parse_all_requirements_files,
         pip_data_exclude = pip_data_exclude,
+        pyproject_toml = pyproject_toml,
         python_interpreter = python_interpreter,
         python_interpreter_target = python_interpreter_target,
         python_version = python_version,