llvm-project/utils/bazel/llvm-project-overlay/llvm/template_rule.bzl

47 lines
1.4 KiB
Python

# This file is licensed under the Apache License v2.0 with LLVM Exceptions.
# See https://llvm.org/LICENSE.txt for license information.
# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
# Rule for simple expansion of template files. This performs a simple
# search over the template file for the keys in substitutions,
# and replaces them with the corresponding values.
#
# Typical usage:
# load("/tools/build_rules/template_rule", "expand_header_template")
# template_rule(
# name = "ExpandMyTemplate",
# src = "my.template",
# out = "my.txt",
# substitutions = {
# "$VAR1": "foo",
# "$VAR2": "bar",
# }
# )
#
# Args:
# name: The name of the rule.
# template: The template file to expand
# out: The destination of the expanded file
# substitutions: A dictionary mapping strings to their substitutions
def template_rule_impl(ctx):
ctx.actions.expand_template(
template = ctx.file.src,
output = ctx.outputs.out,
substitutions = ctx.attr.substitutions,
)
template_rule = rule(
attrs = {
"src": attr.label(
mandatory = True,
allow_single_file = True,
),
"substitutions": attr.string_dict(mandatory = True),
"out": attr.output(mandatory = True),
},
# output_to_genfiles is required for header files.
output_to_genfiles = True,
implementation = template_rule_impl,
)