blob: 1b730931f42e60f01579ef7fdc4facd4b5dbe255 [file] [log] [blame]
# Copyright 2020 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.
# See the License for the specific language governing permissions and
# limitations under the License.
"""
select_file() build rule implementation.
Selects a single file from the outputs of a target by given relative path.
"""
def _impl(ctx):
if ctx.attr.subpath and len(ctx.attr.subpath) == 0:
fail("Subpath can not be empty.")
out = None
canonical = ctx.attr.subpath.replace("\\", "/")
for file_ in ctx.attr.srcs.files.to_list():
if file_.path.replace("\\", "/").endswith(canonical):
out = file_
break
if not out:
files_str = ",\n".join([
str(f.path)
for f in ctx.attr.srcs.files.to_list()
])
fail("Can not find specified file in [%s]" % files_str)
return [DefaultInfo(files = depset([out]))]
select_file = rule(
implementation = _impl,
doc = "Selects a single file from the outputs of a target by given relative path",
attrs = {
"srcs": attr.label(
allow_files = True,
mandatory = True,
doc = "The target producing the file among other outputs",
),
"subpath": attr.string(
mandatory = True,
doc = "Relative path to the file",
),
},
)