kokoro: Streamline check-format (KhronosGroup#5973)

Use a special Docker image that has only the necessary tools.
Avoid downloading clang.

Also, utils/check_code_format.sh can find clang-format and
clang-format-diff.py from CLANG_FORMAT and CLANG_FORMAT_DIFF environment
variables. The Docker image sets those.

BUG=392135092, 397439901

Author: dneto0

kokoro/check-format/build-docker.sh

@@ -0,0 +1,26 @@
+#!/bin/bash
+# Copyright (c) 2025 Google LLC
+#
+# 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.
+
+# Fail on any error.
+set -e
+
+# This is required to run any git command in the docker since owner will
+# have changed between the clone environment, and the docker container.
+# Marking the root of the repo as safe for ownership changes.
+git config --global --add safe.directory "$PWD"
+
+echo $(date): Check formatting...
+./utils/check_code_format.sh ${1:-main}
+echo $(date): check completed.

kokoro/check-format/build.sh

@@ -1,5 +1,5 @@
 #!/bin/bash
-# Copyright (c) 2018 Google LLC.
+# Copyright (c) 2025 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -12,37 +12,16 @@
 # 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.
-#
-# Android Build Script.
 
 # Fail on any error.
 set -e
-# Display commands being run.
-set -x
-
-BUILD_ROOT=$PWD
-SRC=$PWD/github/SPIRV-Tools
-
-# This is required to run any git command in the docker since owner will
-# have changed between the clone environment, and the docker container.
-# Marking the root of the repo as safe for ownership changes.
-git config --global --add safe.directory $SRC
-
-# Get clang-format-5.0.0.
-# Once kokoro upgrades the Ubuntu VMs, we can use 'apt-get install clang-format'
-curl -L http://releases.llvm.org/5.0.0/clang+llvm-5.0.0-linux-x86_64-ubuntu14.04.tar.xz -o clang-llvm.tar.xz
-tar xf clang-llvm.tar.xz
-export PATH=$PWD/clang+llvm-5.0.0-linux-x86_64-ubuntu14.04/bin:$PATH
 
-cd $SRC
-git clone --depth=1 https://github.com/KhronosGroup/SPIRV-Headers external/spirv-headers
-git clone https://github.com/google/googletest          external/googletest
-cd external && cd googletest && git reset --hard 1fb1bb23bb8418dc73a5a9a82bbed31dc610fec7 && cd .. && cd ..
-git clone --depth=1 https://github.com/google/effcee              external/effcee
-git clone --depth=1 https://github.com/google/re2                 external/re2
-# The --fail flag causes the command to fail on HTTP error response codes, like 404.
-curl -L --fail https://raw.githubusercontent.com/llvm/llvm-project/main/clang/tools/clang-format/clang-format-diff.py -o utils/clang-format-diff.py
+SCRIPT_DIR="$( cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd )"
+SRC_ROOT="$( cd "${SCRIPT_DIR}/../.." >/dev/null 2>&1 && pwd )"
+TARGET_BRANCH="${KOKORO_GITHUB_PULL_REQUEST_TARGET_BRANCH-main}"
 
-echo $(date): Check formatting...
-./utils/check_code_format.sh;
-echo $(date): check completed.
+docker run --rm -i \
+  --volume "${SRC_ROOT}:${SRC_ROOT}" \
+  --workdir "${SRC_ROOT}" \
+  "us-east4-docker.pkg.dev/shaderc-build/radial-docker/ubuntu-24.04-amd64/formatter" \
+  "${SCRIPT_DIR}/build-docker.sh" "${TARGET_BRANCH}"

utils/check_code_format.sh

@@ -12,22 +12,41 @@
 # 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.
-#
-# Script to determine if source code in Pull Request is properly formatted.
+
+# This script determines if the source code in a Pull Request is properly formatted.
 # Exits with non 0 exit code if formatting is needed.
-#
-# This script assumes to be invoked at the project root directory.
+# Assumptions:
+#    - git and python3 are on the path
+#    - Runs from the project root diretory.
+#    - 'clang-format' is on the path, or env var CLANG_FORMAT points to it.
+#    - 'clang-format-diff.py' is in the utils directory, or env var
+#       points to it.CLANG_FORMAT_DIFF
 
 BASE_BRANCH=${1:-main}
 
+CLANG_FORMAT=${CLANG_FORMAT:-clang-format}
+if [ ! -f "$CLANG_FORMAT" ]; then
+  echo missing clang-format: set CLANG_FORMAT or put clang-format in the PATH
+  exit 1
+fi
+
+# Find clang-format-diff.py from an environment variable, or use a default
+CLANG_FORMAT_DIFF=${CLANG_FORMAT_DIFF:-./utils/clang-format-diff.py}
+if [ ! -f "$CLANG_FORMAT_DIFF" ]; then
+  echo missing clang-format-diffy.py: set CLANG_FORMAT_DIFF or put it in ./utils/clang-format-diff.py
+  exit 1
+fi
+
+echo "Comparing "$(git rev-parse HEAD)" against $BASE_BRANCH"
+
 FILES_TO_CHECK=$(git diff --name-only ${BASE_BRANCH} | grep -E ".*\.(cpp|cc|c\+\+|cxx|c|h|hpp)$")
 
 if [ -z "${FILES_TO_CHECK}" ]; then
   echo "No source code to check for formatting."
   exit 0
 fi
 
-FORMAT_DIFF=$(git diff -U0 ${BASE_BRANCH} -- ${FILES_TO_CHECK} | python ./utils/clang-format-diff.py -p1 -style=file)
+FORMAT_DIFF=$(git diff -U0 ${BASE_BRANCH} -- ${FILES_TO_CHECK} | python3 "${CLANG_FORMAT_DIFF}" -p1 -style=file -binary "$CLANG_FORMAT")
 
 if [ -z "${FORMAT_DIFF}" ]; then
   echo "All source code in PR properly formatted."