go_mod_tidy_test.sh

#!/bin/bash -u
#
# Copyright 2019 Google Inc.
#
# 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.

# Verifies that we have run `go mod tidy` to keep our modules config clean.

# Go 1.16 seems to differ in how it formats `go mod` using `go mod tidy`, which
# makes it incompatible with all prior versions; see the output logs in
# https://github.com/google/code-review-bot/actions/runs/695615181 for the
# differences in results. Thus, for now, we'll skip this test for Go 1.16 so that:
#
# (a) we can continue to test all other functionality with Go 1.16
# (b) users using Go 1.16 can run `make test` just like everyone else
if [ -n "$(go version | grep 'go1.16')" ]; then
  echo "WARNING: Go 1.16 uses a different format for 'go mod tidy' output." >&2
  echo "WARNING: See https://github.com/google/code-review-bot/actions/runs/695615181 for details." >&2
  echo "WARNING: Skipping $(basename $0) for now." >&2
  exit
fi

declare -r GO_MOD="go.mod"
declare -r GO_SUM="go.sum"

declare -r GO_MOD_ORIG="go.mod.orig"
declare -r GO_SUM_ORIG="go.sum.orig"

declare -i success=0

cp "${GO_MOD}" "${GO_MOD_ORIG}"
cp "${GO_SUM}" "${GO_SUM_ORIG}"

go mod tidy

diff -u "${GO_MOD}" "${GO_MOD_ORIG}" || success=1
diff -u "${GO_SUM}" "${GO_SUM_ORIG}" || success=1

mv "${GO_MOD_ORIG}" "${GO_MOD}"
mv "${GO_SUM_ORIG}" "${GO_SUM}"

if [[ ${success} == 0 ]]; then
  echo PASSED
else
  echo FAILED
fi
exit ${success}