cc/toolchains/actions.bzl

# Copyright 2024 The Bazel Authors. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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"""Rules to turn action types into bazel labels."""

load("//cc/toolchains/impl:collect.bzl", "collect_action_types")
load(":cc_toolchain_info.bzl", "ActionTypeInfo", "ActionTypeSetInfo")

visibility("public")

def _cc_action_type_impl(ctx):
    action_type = ActionTypeInfo(label = ctx.label, name = ctx.attr.action_name)
    return [
        action_type,
        ActionTypeSetInfo(
            label = ctx.label,
            actions = depset([action_type]),
        ),
    ]

cc_action_type = rule(
    implementation = _cc_action_type_impl,
    attrs = {
        "action_name": attr.string(
            mandatory = True,
        ),
    },
    doc = """A type of action (eg. c_compile, assemble, strip).

Example:

load("@rules_cc//cc:action_names.bzl", "ACTION_NAMES")

cc_action_type(
  name = "cpp_compile",
  action_name =  = ACTION_NAMES.cpp_compile,
)
""",
    provides = [ActionTypeInfo, ActionTypeSetInfo],
)

def _cc_action_type_set_impl(ctx):
    if not ctx.attr.actions and not ctx.attr.allow_empty:
        fail("Each cc_action_type_set must contain at least one action type.")
    return [ActionTypeSetInfo(
        label = ctx.label,
        actions = collect_action_types(ctx.attr.actions),
    )]

cc_action_type_set = rule(
    doc = """Represents a set of actions.

Example:

cc_action_type_set(
    name = "link_executable_actions",
    actions = [
        ":cpp_link_executable",
        ":lto_index_for_executable",
    ],
)
""",
    implementation = _cc_action_type_set_impl,
    attrs = {
        "actions": attr.label_list(
            providers = [ActionTypeSetInfo],
            mandatory = True,
            doc = "A list of cc_action_type or cc_action_type_set",
        ),
        "allow_empty": attr.bool(default = False),
    },
    provides = [ActionTypeSetInfo],
)