Conditionally remove builtin PyInfo and other providers

Use bazel_features to detect if PyInfo is still present in Bazel and
stop using it, if it's not.

Bazel throws an error while compiling bzl files if there is a
reference to a top-level symbol that doesn't exist anymore.
bazel_features provide a mechanism that detects presence of top-level
symbols without throwing an exception. It either returns the symbol or None.

bazel_features support not only Bazel 8, but also older versions of
Bazel that have --incompatible_autoload_externally cherry-picked. If the
flag is enabled with "@rules_python" or "-@rules_python" the provider is
removed from Bazel.

Remove also PyRuntimeInfo and PyCcLinkParamsProvider.

Author: comius

MODULE.bazel

@@ -4,7 +4,7 @@ module(
     compatibility_level = 1,
 )
 
-bazel_dep(name = "bazel_features", version = "1.9.1")
+bazel_dep(name = "bazel_features", version = "1.18.0")
 bazel_dep(name = "bazel_skylib", version = "1.6.1")
 bazel_dep(name = "rules_cc", version = "0.0.9")
 bazel_dep(name = "platforms", version = "0.0.4")

internal_deps.bzl

@@ -212,9 +212,9 @@ def rules_python_internal_deps():
 
     http_archive(
         name = "bazel_features",
-        sha256 = "d7787da289a7fb497352211ad200ec9f698822a9e0757a4976fd9f713ff372b3",
-        strip_prefix = "bazel_features-1.9.1",
-        url = "https://github.com/bazel-contrib/bazel_features/releases/download/v1.9.1/bazel_features-v1.9.1.tar.gz",
+        sha256 = "b4b145c19e08fd48337f53c383db46398d0a810002907ff0c590762d926e05be",
+        strip_prefix = "bazel_features-1.18.0",
+        url = "https://github.com/bazel-contrib/bazel_features/releases/download/v1.18.0/bazel_features-v1.18.0.tar.gz",
     )
 
     http_archive(

python/config_settings/transition.bzl

@@ -101,12 +101,12 @@ def _transition_py_impl(ctx):
     ]
     if PyInfo in target:
         providers.append(target[PyInfo])
-    if BuiltinPyInfo in target and PyInfo != BuiltinPyInfo:
+    if BuiltinPyInfo != None and BuiltinPyInfo in target and PyInfo != BuiltinPyInfo:
         providers.append(target[BuiltinPyInfo])
 
     if PyRuntimeInfo in target:
         providers.append(target[PyRuntimeInfo])
-    if BuiltinPyRuntimeInfo in target and PyRuntimeInfo != BuiltinPyRuntimeInfo:
+    if BuiltinPyRuntimeInfo != None and BuiltinPyRuntimeInfo in target and PyRuntimeInfo != BuiltinPyRuntimeInfo:
         providers.append(target[BuiltinPyRuntimeInfo])
     return providers
 

python/private/BUILD.bazel

@@ -341,7 +341,10 @@ bzl_library(
     visibility = [
         "//:__subpackages__",
     ],
-    deps = [":bazel_tools_bzl"],
+    deps = [
+        ":bazel_tools_bzl",
+        "@bazel_features//:features",
+    ],
 )
 
 bzl_library(

python/private/common/attributes.bzl

@@ -253,15 +253,16 @@ COMMON_ATTRS = union_attrs(
     allow_none = True,
 )
 
+_MaybeBuiltinPyInfo = [[BuiltinPyInfo]] if BuiltinPyInfo != None else []
+
 # Attributes common to rules accepting Python sources and deps.
 PY_SRCS_ATTRS = union_attrs(
     {
         "deps": attr.label_list(
             providers = [
                 [PyInfo],
                 [CcInfo],
-                [BuiltinPyInfo],
-            ],
+            ] + _MaybeBuiltinPyInfo,
             # TODO(b/228692666): Google-specific; remove these allowances once
             # the depot is cleaned up.
             allow_rules = DEPS_ATTR_ALLOW_RULES,

python/private/common/common.bzl

@@ -280,7 +280,7 @@ def collect_imports(ctx, semantics):
         dep[BuiltinPyInfo].imports
         for dep in ctx.attr.deps
         if BuiltinPyInfo in dep
-    ])
+    ] if BuiltinPyInfo != None else [])
 
 def collect_runfiles(ctx, files = depset()):
     """Collects the necessary files from the rule's context.
@@ -374,7 +374,7 @@ def create_py_info(ctx, *, direct_sources, direct_pyc_files, imports):
 
     for target in ctx.attr.deps:
         # PyInfo may not be present e.g. cc_library rules.
-        if PyInfo in target or BuiltinPyInfo in target:
+        if PyInfo in target or (BuiltinPyInfo != None and BuiltinPyInfo in target):
             py_info.merge(_get_py_info(target))
         else:
             # TODO(b/228692666): Remove this once non-PyInfo targets are no
@@ -395,7 +395,7 @@ def create_py_info(ctx, *, direct_sources, direct_pyc_files, imports):
         for target in ctx.attr.data:
             # TODO(b/234730058): Remove checking for PyInfo in data once depot
             # cleaned up.
-            if PyInfo in target or BuiltinPyInfo in target:
+            if PyInfo in target or (BuiltinPyInfo != None and BuiltinPyInfo in target):
                 info = _get_py_info(target)
                 py_info.merge_uses_shared_libraries(info.uses_shared_libraries)
             else:
@@ -410,7 +410,7 @@ def create_py_info(ctx, *, direct_sources, direct_pyc_files, imports):
     return py_info.build(), deps_transitive_sources, py_info.build_builtin_py_info()
 
 def _get_py_info(target):
-    return target[PyInfo] if PyInfo in target else target[BuiltinPyInfo]
+    return target[PyInfo] if PyInfo in target or BuiltinPyInfo == None else target[BuiltinPyInfo]
 
 def create_instrumented_files_info(ctx):
     return _coverage_common.instrumented_files_info(

python/private/common/py_executable.bzl

@@ -855,7 +855,7 @@ def _create_providers(
         # builtin py_runtime rule or defined their own. We can't directly detect
         # the type of the provider object, but the rules_python PyRuntimeInfo
         # object has an extra attribute that the builtin one doesn't.
-        if hasattr(py_runtime_info, "interpreter_version_info"):
+        if hasattr(py_runtime_info, "interpreter_version_info") and BuiltinPyRuntimeInfo != None:
             providers.append(BuiltinPyRuntimeInfo(
                 interpreter_path = py_runtime_info.interpreter_path,
                 interpreter = py_runtime_info.interpreter,

python/private/common/py_runtime_rule.bzl

@@ -125,18 +125,20 @@ def _py_runtime_impl(ctx):
     if not IS_BAZEL_7_OR_HIGHER:
         builtin_py_runtime_info_kwargs.pop("bootstrap_template")
 
-    return [
+    providers = [
         PyRuntimeInfo(**py_runtime_info_kwargs),
-        # Return the builtin provider for better compatibility.
-        # 1. There is a legacy code path in py_binary that
-        #    checks for the provider when toolchains aren't used
-        # 2. It makes it easier to transition from builtins to rules_python
-        BuiltinPyRuntimeInfo(**builtin_py_runtime_info_kwargs),
         DefaultInfo(
             files = runtime_files,
             runfiles = runfiles,
         ),
     ]
+    if BuiltinPyRuntimeInfo != None:
+        # Return the builtin provider for better compatibility.
+        # 1. There is a legacy code path in py_binary that
+        #    checks for the provider when toolchains aren't used
+        # 2. It makes it easier to transition from builtins to rules_python
+        providers.append(BuiltinPyRuntimeInfo(**builtin_py_runtime_info_kwargs))
+    return providers
 
 # Bind to the name "py_runtime" to preserve the kind/rule_class it shows up
 # as elsewhere.

python/private/py_info.bzl

@@ -118,7 +118,7 @@ This field is currently unused in Bazel and may go away in the future.
 )
 
 # The "effective" PyInfo is what the canonical //python:py_info.bzl%PyInfo symbol refers to
-_EffectivePyInfo = PyInfo if config.enable_pystar else BuiltinPyInfo
+_EffectivePyInfo = PyInfo if config.enable_pystar or BuiltinPyInfo == None else BuiltinPyInfo
 
 def PyInfoBuilder():
     # buildifier: disable=uninitialized
@@ -201,7 +201,7 @@ def _PyInfoBuilder_merge_all(self, py_infos):
 def _PyInfoBuilder_merge_target(self, target):
     if PyInfo in target:
         self.merge(target[PyInfo])
-    elif BuiltinPyInfo in target:
+    elif BuiltinPyInfo != None and BuiltinPyInfo in target:
         self.merge(target[BuiltinPyInfo])
     return self
 

python/private/py_repositories.bzl

@@ -46,4 +46,10 @@ def py_repositories():
         sha256 = "2037875b9a4456dce4a79d112a8ae885bbc4aad968e6587dca6e64f3a0900cdf",
         strip_prefix = "rules_cc-0.0.9",
     )
+    http_archive(
+        name = "bazel_features",
+        sha256 = "b4b145c19e08fd48337f53c383db46398d0a810002907ff0c590762d926e05be",
+        strip_prefix = "bazel_features-1.18.0",
+        url = "https://github.com/bazel-contrib/bazel_features/releases/download/v1.18.0/bazel_features-v1.18.0.tar.gz",
+    )
     pypi_deps()