add current_py_cc_headers_abi3 target

Author: rickeylev

python/cc/BUILD.bazel

@@ -2,7 +2,7 @@
 
 load("@bazel_skylib//:bzl_library.bzl", "bzl_library")
 load("//python/private:bzlmod_enabled.bzl", "BZLMOD_ENABLED")
-load("//python/private:current_py_cc_headers.bzl", "current_py_cc_headers")
+load("//python/private:current_py_cc_headers.bzl", "current_py_cc_headers", "current_py_cc_headers_abi3")
 load("//python/private:current_py_cc_libs.bzl", "current_py_cc_libs")
 
 package(
@@ -20,6 +20,17 @@ current_py_cc_headers(
     visibility = ["//visibility:public"],
 )
 
+# This target provides the C ABI3 headers for whatever the current toolchain is
+# for the consuming rule. It basically acts like a cc_library by forwarding
+# on the providers for the underlying cc_library that the toolchain is using.
+current_py_cc_headers_abi3(
+    name = "current_py_cc_headers_abi3",
+    # Building this directly will fail unless a py cc toolchain is registered,
+    # and it's only under bzlmod that one is registered by default.
+    tags = [] if BZLMOD_ENABLED else ["manual"],
+    visibility = ["//visibility:public"],
+)
+
 # This target provides the C libraries for whatever the current toolchain is for
 # the consuming rule. It basically acts like a cc_library by forwarding on the
 # providers for the underlying cc_library that the toolchain is using.

python/private/current_py_cc_headers.bzl

@@ -12,7 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-"""Implementation of current_py_cc_headers rule."""
+"""Implementation of current_py_cc_headers and current_py_cc_headers_abi3 rules.
+"""
 
 load("@rules_cc//cc/common:cc_info.bzl", "CcInfo")
 
@@ -24,7 +25,7 @@ current_py_cc_headers = rule(
     implementation = _current_py_cc_headers_impl,
     toolchains = ["//python/cc:toolchain_type"],
     provides = [CcInfo],
-    doc = """\
+    doc = """
 Provides the currently active Python toolchain's C headers.
 
 This is a wrapper around the underlying `cc_library()` for the
@@ -41,3 +42,35 @@ cc_library(
 ```
 """,
 )
+
+def _current_py_cc_headers_abi3_impl(ctx):
+    py_cc_toolchain = ctx.toolchains["//python/cc:toolchain_type"].py_cc_toolchain
+    if not py_cc_toolchain.headers_abi3:
+        fail(
+            "The current python toolchain does not provide ABI3 headers".format(
+                py_cc_toolchain.python_version,
+            ),
+        )
+    return py_cc_toolchain.headers_abi3.providers_map.values()
+
+current_py_cc_headers_abi3 = rule(
+    implementation = _current_py_cc_headers_abi3_impl,
+    toolchains = ["//python/cc:toolchain_type"],
+    provides = [CcInfo],
+    doc = """
+Provides the currently active Python toolchain's C ABI3 headers.
+
+This is a wrapper around the underlying `cc_library()` for the
+C ABI3 headers for the consuming target's currently active Python toolchain.
+
+To use, simply depend on this target where you would have wanted the
+toolchain's underlying `:python_headers_abi3` target:
+
+```starlark
+cc_library(
+    name = "foo",
+    deps = ["@rules_python//python/cc:current_py_cc_headers_abi3"]
+)
+```
+""",
+)