Ignore selected paths for clang-format and clang-tidy

Now clang-format report will skip files matching `clang-format.ignore`.
For now it's empty.

clang-tidy will not receive diffs for `clang-tidy.ignore` (it still can
produce warnings for these files).
In addition build bot will not will not post comments for files
that are matched by `clang-tidy-comments.ignore`. Now project/file should
be whitelisted to receive inline comments from clang-tidy.

Added all /test directories to `clang-tidy.ignore`.

Other alternatives considered:

- using 'compile_commands.json': does not contain header files.
- specifying -regex option to 'clang-tidy-diff': probably not the best
  experience of providing multiple rules and maintaining a single regex.

.gitignore

@@ -1,3 +1,5 @@
 .vscode/
 .idea/
 *.iml
+venv/
+__pycache__/

Jenkins/Phabricator-pipeline/Jenkinsfile

@@ -149,6 +149,7 @@ pipeline {
                 --buildresult ${currentBuild.result} \
                 --clang-format-patch "clang-format.patch" \
                 --clang-tidy-result "clang-tidy.txt" \
+                --clang-tidy-ignore "${SCRIPT_DIR}/clang-tidy-comments.ignore" \
                 --results-dir "${TARGET_DIR}" \
                 --results-url "${RESULT_URL}"
                 """

scripts/clang-format.ignore

@@ -0,0 +1 @@
+# Patterns for clang-format to ignore.

scripts/clang-tidy-comments.ignore

@@ -0,0 +1,4 @@
+# Files that are allowed by clang-tidy.ignore but should not receive inline review comments.
+# Right now it works in whitelist mode and only some files / directories are whitelisted.
+*
+!clang-tools-extra/clangd/**

scripts/clang-tidy.ignore

@@ -0,0 +1,44 @@
+# Files to be ignored by clang-tidy. Will not appear in short report and inline comments.
+libcxxabi/test
+libcxxabi/test/libcxxabi/test
+libcxx/test
+libcxx/utils/libcxx/test
+libcxx/utils/google-benchmark/test
+llvm/test
+llvm/utils/gn/secondary/llvm/test
+llvm/utils/gn/secondary/lld/test
+llvm/utils/gn/secondary/clang-tools-extra/test
+llvm/utils/gn/secondary/clang-tools-extra/clangd/test
+llvm/utils/gn/secondary/compiler-rt/test
+llvm/utils/gn/secondary/clang/test
+llvm/utils/benchmark/test
+polly/test
+lldb/examples/test
+lldb/test
+lldb/utils/test
+lldb/tools/intel-features/intel-mpx/test
+lldb/packages/Python/lldbsuite/test
+lldb/packages/Python/lldbsuite/test/tools/lldb-server/test
+lldb/packages/Python/lldbsuite/test/commands/expression/test
+lldb/packages/Python/lldbsuite/test/test_runner/test
+lldb/third_party/Python/module/unittest2/unittest2/test
+lld/test
+clang-tools-extra/test
+clang-tools-extra/clangd/clients/clangd-vscode/test
+clang-tools-extra/clangd/test
+pstl/test
+libc/test
+llgo/test
+compiler-rt/test
+compiler-rt/test/builtins/Unit/ppc/test
+compiler-rt/test/builtins/Unit/test
+debuginfo-tests/dexter/dex/tools/test
+debuginfo-tests/dexter/feature_tests/subtools/test
+clang/test
+libclc/test
+mlir/test
+openmp/libomptarget/test
+openmp/libomptarget/deviceRTLs/nvptx/test
+openmp/runtime/test
+libunwind/test
+libunwind/test/libunwind/test

scripts/ignore_diff.py

@@ -0,0 +1,39 @@
+#!/usr/bin/env python3
+# Copyright 2020 Google LLC
+#
+# Licensed under the the Apache License v2.0 with LLVM Exceptions (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://llvm.org/LICENSE.txt
+#
+# 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.
+
+import re
+import sys
+import pathspec
+
+# Takes an output of git diff and removes files ignored by patten specified by ignore file.
+def main():
+    argv = sys.argv[1:]
+    if not argv:
+        print("Please provide a path to .ignore file.")
+        sys.exit(1)
+    ignore = pathspec.PathSpec.from_lines(pathspec.patterns.GitWildMatchPattern,
+                                          open(argv[0], 'r').readlines())
+    good = True
+    for line in sys.stdin:
+        match = re.search(r'^diff --git a/(.*) b/(.*)$', line)
+        if match:
+            good = not (ignore.match_file(match.group(1)) and ignore.match_file(match.group(2)))
+        if not good:
+            continue
+        sys.stdout.write(line)
+
+
+if __name__ == "__main__":
+    main()

scripts/lint.sh

@@ -21,16 +21,17 @@ set -eux
 echo "Running linters... ====================================="
 
 cd "${WORKSPACE}"
+
+# clang-format
 # Let clang format apply patches --diff doesn't produces results in the format we want.
 git-clang-format
 set +e
-git diff -U0 --exit-code > "${TARGET_DIR}"/clang-format.patch
-STATUS="${PIPESTATUS[0]}"
+git diff -U0 --exit-code | "${SCRIPT_DIR}/ignore_diff.py" "${SCRIPT_DIR}/clang-format.ignore" > "${TARGET_DIR}"/clang-format.patch
 set -e
 # Revert changes of git-clang-format.
 git checkout -- .
 
-# TODO: clang tidy is currently disabled, see https://github.com/google/llvm-premerge-checks/issues/91
-# git diff HEAD^ | clang-tidy-diff -p1 -quiet > "${TARGET_DIR}"/clang-tidy.txt
+# clang-tidy
+git diff -U0 HEAD^ | "${SCRIPT_DIR}/ignore_diff.py" "${SCRIPT_DIR}/clang-tidy.ignore" | clang-tidy-diff -p1 -quiet > "${TARGET_DIR}"/clang-tidy.txt
 
 echo "linters completed ======================================"

scripts/phabtalk/apply_patch.py

@@ -1,4 +1,4 @@
-#!/bin/env python3
+#!/usr/bin/env python3
 # Copyright 2019 Google LLC
 #
 # Licensed under the the Apache License v2.0 with LLVM Exceptions (the "License");

scripts/phabtalk/phabtalk.py

@@ -24,6 +24,7 @@ import socket
 import time
 from typing import Optional
 
+import pathspec
 from lxml import etree
 from phabricator import Phabricator
 
@@ -48,6 +49,7 @@ class BuildReport:
             self.lint[key] = []
         self.lint[key].append(m)
 
+
 class PhabTalk:
     """Talk to Phabricator to upload build results.
        See https://secure.phabricator.com/conduit/method/harbormaster.sendmessage/
@@ -213,18 +215,25 @@ def _add_clang_format(report: BuildReport, results_dir: str,
     report.success = success and report.success
 
 
-def _add_clang_tidy(report: BuildReport, results_dir: str, results_url: str, workspace: str, clang_tidy_file: str):
+def _add_clang_tidy(report: BuildReport, results_dir: str, results_url: str, workspace: str, clang_tidy_file: str,
+                    clang_tidy_ignore: str):
     # Typical message looks like
     # [..]/clang/include/clang/AST/DeclCXX.h:3058:20: error: no member named 'LifetimeExtendedTemporary' in 'clang::Decl' [clang-diagnostic-error]
-
     pattern = '^{}/([^:]*):(\\d+):(\\d+): (.*): (.*)'.format(workspace)
-    success = True
+    errors_count = 0
+    warn_count = 0
     present = (clang_tidy_file is not None) and os.path.exists(os.path.join(results_dir, clang_tidy_file))
     if not present:
         print('clang-tidy result {} is not found'.format(clang_tidy_file))
         report.comments.append(section_title('clang-tidy', False, False))
         return
-
+    present = (clang_tidy_ignore is not None) and os.path.exists(clang_tidy_ignore)
+    if not present:
+        print('clang-tidy ignore file {} is not found'.format(clang_tidy_ignore))
+        report.comments.append(section_title('clang-tidy', False, False))
+        return
+    ignore = pathspec.PathSpec.from_lines(pathspec.patterns.GitWildMatchPattern,
+                                          open(clang_tidy_ignore, 'r').readlines())
     p = os.path.join(results_dir, clang_tidy_file)
     for line in open(p, 'r'):
         match = re.search(pattern, line)
@@ -235,20 +244,27 @@ def _add_clang_tidy(report: BuildReport, results_dir: str, results_url: str, wor
             severity = match.group(4)
             text = match.group(5)
             if severity in ['warning', 'error']:
-                success = False
-                report.addLint({
-                    'name': 'clang-tidy',
-                    'severity': 'warning',
-                    'code': 'clang-tidy',
-                    'path': file_name,
-                    'line': int(line_pos),
-                    'char': int(char_pos),
-                    'description': '{}: {}'.format(severity, text),
-                })
-
+                if severity == 'warning':
+                    warn_count += 1
+                if severity == 'error':
+                    errors_count += 1
+                if ignore.match_file(file_name):
+                    print('{} is ignored by pattern and no comment will be added')
+                else:
+                    report.addLint({
+                        'name': 'clang-tidy',
+                        'severity': 'warning',
+                        'code': 'clang-tidy',
+                        'path': file_name,
+                        'line': int(line_pos),
+                        'char': int(char_pos),
+                        'description': '{}: {}'.format(severity, text),
+                    })
+    success = errors_count + warn_count == 0
     comment = section_title('clang-tidy', success, present)
     if not success:
-        comment += 'Please fix [[ {}/{} | clang-tidy findings ]].'.format(results_url, clang_tidy_file)
+        comment += 'clang-tidy found [[ {}/{} | {} errors and {} warnings]].'\
+            .format(results_url, clang_tidy_file, errors_count, warn_count)
     report.comments.append(comment)
     report.success = success and report.success
 
@@ -355,7 +371,8 @@ def main():
             report.success = False
 
     _add_test_results(report, args.results_dir, args.test_result_file)
-    _add_clang_tidy(report, args.results_dir, args.results_url, args.workspace, args.clang_tidy_result)
+    _add_clang_tidy(report, args.results_dir, args.results_url, args.workspace, args.clang_tidy_result,
+                    args.clang_tidy_ignore)
     _add_clang_format(report, args.results_dir, args.results_url, args.clang_format_patch)
     _add_links_to_artifacts(report, args.results_dir, args.results_url)
     p = PhabTalk(args.conduit_token, args.host, args.dryrun)
@@ -380,6 +397,9 @@ def _parse_args():
     parser.add_argument('--clang-tidy-result', type=str, default=None,
                         dest='clang_tidy_result',
                         help="path to diff produced by git-clang-tidy, relative to results-dir")
+    parser.add_argument('--clang-tidy-ignore', type=str, default=None,
+                        dest='clang_tidy_ignore',
+                        help="path to file with patters to exclude commenting on for clang-tidy findings")
     parser.add_argument('--results-dir', type=str, default=None, required=True,
                         dest='results_dir',
                         help="directory of all build artifacts")

scripts/phabtalk/requirements.txt

@@ -2,4 +2,4 @@ phabricator==0.7.0
 lxml==4.4.1
 gitpython==3.0.5
 retrying==1.3.3
-pathspec==0.7.0
+pathspec=0.7.0