xref: /aosp_15_r20/external/federated-compute/fcp/base/golden_file.bzl (revision 14675a029014e728ec732f129a32e299b2da0601)
1# Copyright 2018 Google LLC
2#
3# Licensed under the Apache License, Version 2.0 (the "License");
4# you may not use this file except in compliance with the License.
5# You may obtain a copy of the License at
6#
7#      http://www.apache.org/licenses/LICENSE-2.0
8#
9# Unless required by applicable law or agreed to in writing, software
10# distributed under the License is distributed on an "AS IS" BASIS,
11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12# See the License for the specific language governing permissions and
13# limitations under the License.
14
15"""Provides the golden_file_test() rule."""
16
17GOLDEN_FILE_CHECKER_TEMPLATE = """
18#!/bin/bash
19set -o nounset
20set -o errexit
21
22readonly EXPECTED={EXPECTED}
23readonly ACTUAL={ACTUAL}
24
25diff -u --label EXPECTED "$EXPECTED" --label ACTUAL "$ACTUAL"
26readonly r=$?
27
28if (( $r != 0 )); then
29  echo "***" >&2
30  echo "*** FAIL: Contents of $ACTUAL do not match $EXPECTED" >&2
31  echo "***" >&2
32fi
33
34exit $r
35"""
36
37def _golden_file_test_impl(ctx):
38    replacements = {
39        "{EXPECTED}": repr(ctx.file.expected.short_path),
40        "{ACTUAL}": repr(ctx.file.actual.short_path),
41    }
42
43    contents = GOLDEN_FILE_CHECKER_TEMPLATE
44    for k, v in replacements.items():
45        contents = contents.replace(k, v)
46
47    ctx.actions.write(
48        ctx.outputs.sh,
49        contents,
50        is_executable = True,
51    )
52
53    runfiles = ctx.runfiles(files = [ctx.file.expected, ctx.file.actual])
54    return [DefaultInfo(executable = ctx.outputs.sh, runfiles = runfiles)]
55
56golden_file_test = rule(
57    implementation = _golden_file_test_impl,
58    outputs = {"sh": "%{name}.sh"},
59    test = True,
60    attrs = {
61        "actual": attr.label(allow_single_file = True),
62        "expected": attr.label(allow_single_file = True),
63    },
64)
65"""Checks that two files are equal; fails with a text diff otherwise."""
66