Create a symbolic macro if supported (#138)

With Bazel 8 and if the wrapped kind is not a legacy macro, create a
symbolic macro instead of a legacy macro.

Also update stardoc to the latest version to get `load` statements.

BUILD.bazel

@@ -1,6 +1,12 @@
 load("@bazel_skylib//:bzl_library.bzl", "bzl_library")
 load("@bazel_skylib//rules:common_settings.bzl", "bool_flag")
 
+# For stardoc to reference the files
+exports_files(
+    ["with_cfg.bzl"],
+    visibility = ["//docs:__pkg__"],
+)
+
 bzl_library(
     name = "with_cfg",
     srcs = ["with_cfg.bzl"],

MODULE.bazel

@@ -4,6 +4,7 @@ module(
     compatibility_level = 1,
 )
 
+bazel_dep(name = "bazel_features", version = "1.22.0")
 bazel_dep(name = "bazel_skylib", version = "1.4.1")
 bazel_dep(name = "platforms", version = "0.0.6")
 
@@ -12,15 +13,9 @@ bazel_dep(name = "bazel_skylib_gazelle_plugin", version = "1.4.1", dev_dependenc
 bazel_dep(name = "buildifier_prebuilt", version = "6.4.0", dev_dependency = True)
 bazel_dep(name = "gazelle", version = "0.33.0", dev_dependency = True, repo_name = "bazel_gazelle")
 bazel_dep(name = "rules_testing", version = "0.4.0", dev_dependency = True)
-bazel_dep(name = "stardoc", dev_dependency = True)
-git_override(
-    module_name = "stardoc",
-    commit = "3baa5d1761970c6285d2ac9c3adccfaac42f54c5",
-    remote = "https://github.com/bazelbuild/stardoc.git",
-)
-
 bazel_dep(name = "rules_java", version = "7.6.1", dev_dependency = True)
 bazel_dep(name = "rules_proto", version = "6.0.0", dev_dependency = True)
+bazel_dep(name = "stardoc", version = "0.7.2", dev_dependency = True)
 bazel_dep(name = "toolchains_protoc", version = "0.3.0", dev_dependency = True)
 
 protoc = use_extension(

docs/BUILD.bazel

@@ -5,7 +5,7 @@ load("@rules_proto//proto:proto_lang_toolchain.bzl", "proto_lang_toolchain")
 
 stardoc_with_diff_test(
     name = "defs",
-    bzl_library_target = "//with_cfg:defs",
+    bzl_library_target = "//:with_cfg",
 )
 
 update_docs(name = "update")

with_cfg/BUILD.bazel

@@ -1,6 +1,6 @@
 load("@bazel_skylib//:bzl_library.bzl", "bzl_library")
 
-# For stardoc to reference the files
+# Legacy export, no longer used by this module.
 exports_files(["defs.bzl"])
 
 bzl_library(

with_cfg/private/BUILD.bazel

@@ -153,5 +153,6 @@ bzl_library(
         ":select",
         ":setting",
         ":utils",
+        "@bazel_features//:features",
     ],
 )

with_cfg/private/providers.bzl

@@ -9,6 +9,7 @@ RuleInfo = provider(fields = [
     "kind",
     "native",
     "providers",
+    "supports_inheritance",
     "test",
 ])
 

with_cfg/private/with_cfg.bzl

@@ -127,6 +127,7 @@ def with_cfg(
         implicit_targets = implicit_targets,
         providers = DEFAULT_PROVIDERS + extra_providers,
         native = _is_native(kind),
+        supports_inheritance = _supports_inheritance(kind),
     )
     return make_builder(rule_info)
 
@@ -155,5 +156,9 @@ def is_test(rule_name):
 def _is_native(kind):
     return str(kind).startswith("<built-in rule ")
 
+def _supports_inheritance(kind):
+    # Legacy macros don't support inheritance.
+    return not str(kind).startswith("<function ")
+
 def get_implicit_targets(rule_name):
     return IMPLICIT_TARGETS.get(rule_name, [])

with_cfg/private/wrapper.bzl

@@ -1,3 +1,4 @@
+load("@bazel_features//:features.bzl", "bazel_features")
 load(":args.bzl", "rewrite_args")
 load(":rewrite.bzl", "make_label_rewriter", "rewrite_locations_in_attr")
 load(":select.bzl", "map_attr")
@@ -15,7 +16,7 @@ def make_wrapper(
         values,
         original_settings_label,
         attrs_to_reset):
-    return lambda *, name, **kwargs: _wrapper(
+    wrapper_impl = lambda *, name, **kwargs: _wrapper(
         name = name,
         kwargs = kwargs,
         rule_info = rule_info,
@@ -25,6 +26,12 @@ def make_wrapper(
         original_settings_label = original_settings_label,
         attrs_to_reset = attrs_to_reset,
     )
+    if bazel_features.globals.macro and rule_info.supports_inheritance:
+        return bazel_features.globals.macro(
+            implementation = wrapper_impl,
+            inherit_attrs = rule_info.kind,
+        )
+    return wrapper_impl
 
 # Attributes common to all rules.
 # These attributes are applied to all targets generated by the wrapper.