Use pre-commit to check C++ and Python formatting

See merge request !1261

.clang-format

@@ -112,4 +112,8 @@ SpacesInParentheses: true
 Standard:        Cpp11
 TabWidth:        8
 UseTab:          Never
+---
+Language: ObjC
+# Don't format Objective-C, Objective-C++ files.
+DisableFormat: true
 ...

.gitlab-ci.yml

@@ -226,14 +226,44 @@ x86_64-centos7-gcc10-opt:check-unused:
     - ci-utils/check-sources build/build.ninja
   allow_failure: true
 
-check-formatting:
+pre-commit-checks:
   stage: pre-build-checks
-  image: gitlab-registry.cern.ch/gaudi/gaudi/format-checker:latest
+  image: registry.cern.ch/docker.io/library/python:3.8
+  variables:
+    PRE_COMMIT_HOME: ${CI_PROJECT_DIR}/.cache/pre-commit
+  cache:
+    paths:
+      - ${PRE_COMMIT_HOME}
+  before_script:
+    - |
+      python -m venv ${CI_PROJECT_DIR}/.cache/pre-commit-venv
+      . ${CI_PROJECT_DIR}/.cache/pre-commit-venv/bin/activate
+      pip install pre-commit
+      git fetch origin $TARGET_BRANCH
+      git config user.name "Gitlab CI"
+      git config user.email "noreply@cern.ch"
   script:
-    - ci-utils/check-formatting
+    - |
+      if ! pre-commit run --show-diff-on-failure --from-ref FETCH_HEAD --to-ref HEAD ; then
+        echo ""
+        echo "Generating patch file..."
+        git commit -a -m "pre-commit fixes
+        
+      patch generated by ${CI_JOB_URL}" > /dev/null
+        git format-patch HEAD~
+        cat <<EOF
+      =======================================
+       You can apply these changes with:
+
+          curl ${CI_JOB_URL}/artifacts/raw/0001-pre-commit-fixes.patch | git am
+
+      =======================================
+      EOF
+        exit 1
+      fi
   artifacts:
     paths:
-      - apply-formatting.patch
+      - 0001-pre-commit-fixes.patch
     when: on_failure
     expire_in: 1 week
   allow_failure: true

.pre-commit-config.yaml

+repos:
+-   repo: https://github.com/ssciwr/clang-format-precommit
+    rev: v13.0.0
+    hooks:
+    -   id: clang-format
+    -   id: clang-format
+        name: clang-format (non-standard extensions)
+        types_or: [file]
+        files: \.(icc|icpp)$
+-   repo: https://github.com/pre-commit/mirrors-yapf
+    rev: v0.24.0
+    hooks:
+    -   id: yapf
+        name: Format Python files

ci-utils/check-formatting

-#!/bin/bash -e
-#####################################################################################
-# (c) Copyright 1998-2019 CERN for the benefit of the LHCb and ATLAS collaborations #
-#                                                                                   #
-# This software is distributed under the terms of the Apache version 2 licence,     #
-# copied verbatim in the file "LICENSE".                                            #
-#                                                                                   #
-# In applying this licence, CERN does not waive the privileges and immunities       #
-# granted to it by virtue of its status as an Intergovernmental Organization        #
-# or submit itself to any jurisdiction.                                             #
-#####################################################################################
-
-if [ -n "${CI}" ] ; then
-  job_id="${CI_JOB_URL}"
-else
-  job_id="standalone job"
-fi
-
-# make sure we have the right versions of the commands
-YAPF_VERSION=0.24.0
-if [ "$(yapf --version)" != "yapf $YAPF_VERSION" ] ; then
-  echo "invalid version of yapf: $(yapf --version) ($YAPF_VERSION required)"
-  exit 1
-fi
-
-CLANG_FORMAT_VERSION=8
-if ! which clang-format-$CLANG_FORMAT_VERSION >/dev/null ; then
-  echo "clang-format-$CLANG_FORMAT_VERSION command not available"
-  exit 1
-fi
-
-if [ -n "${TARGET_BRANCH:=$1}" ] ; then
-  git fetch https://gitlab.cern.ch/gaudi/Gaudi.git ${TARGET_BRANCH}
-  files_to_check() {
-    git diff --name-only --no-renames --diff-filter MA FETCH_HEAD...HEAD
-  }
-else
-  files_to_check() {
-    git ls-files
-  }
-fi
-
-files_to_check | \
-  grep -E '\.(i?[ch](pp|xx|c)?|cc|hh)$' | xargs --no-run-if-empty --max-procs=$(nproc) --max-args=100 clang-format-$CLANG_FORMAT_VERSION -i --style=file || true
-files_to_check | \
-  grep -E '\.py$' | xargs --no-run-if-empty --max-procs=$(nproc) --max-args=100 yapf -i || true
-files_to_check | grep -v -E '\.(i?[ch](pp|xx|c)?|cc|hh|py)$' | \
-  xargs --no-run-if-empty awk 'FNR>1{nextfile} /^#!.*python/{print FILENAME; nextfile}' | \
-  xargs --no-run-if-empty --max-procs=$(nproc) --max-args=100 yapf -i || true
-
-if git diff --exit-code --quiet ; then
-  echo "no change"
-else
-  echo "From: Gitlab CI <noreply@cern.ch>" > apply-formatting.patch
-  echo "Date: $(date -R)" >> apply-formatting.patch
-  echo "Subject: [PATCH] Fixed formatting" >> apply-formatting.patch
-  echo "" >> apply-formatting.patch
-  echo "patch generated by ${job_id}" >> apply-formatting.patch
-  echo "" >> apply-formatting.patch
-  echo "" >> apply-formatting.patch
-  git diff >> apply-formatting.patch
-  if [ -n "${CI}" ] ; then
-    cat <<EOF
-=======================================
- You can fix formatting with:
-
-   curl ${CI_JOB_URL}/artifacts/raw/apply-formatting.patch | git am
-
-=======================================
-EOF
-  else
-    echo "Changes made to files and recorded as 'apply-formatting.patch'."
-    echo "You can commit them with:"
-    echo "  git commit -a -m 'Fixed formatting'"
-    echo "or discard all non staged changes with:"
-    echo "  git checkout ."
-  fi
-  exit 1
-fi