Benchmark configuration_loader

I noticed some performance problems in configuration_loader,
particularly if there is no config file present. Add a benchmark to make
it easier to track down the bug.

Author: strager

benchmark/CMakeLists.txt

@@ -21,6 +21,10 @@ quick_lint_js_add_benchmark_executable(
   quick-lint-js-benchmark-cli-location
   benchmark-cli-location.cpp
 )
+quick_lint_js_add_benchmark_executable(
+  quick-lint-js-benchmark-configuration-loader
+  benchmark-configuration-loader.cpp
+)
 quick_lint_js_add_benchmark_executable(
   quick-lint-js-benchmark-document
   benchmark-document.cpp

benchmark/benchmark-configuration-loader.cpp

@@ -0,0 +1,64 @@
+// Copyright (C) 2020  Matthew Glazar
+// See end of file for extended copyright information.
+
+#include <benchmark/benchmark.h>
+#include <quick-lint-js/configuration-loader.h>
+#include <quick-lint-js/file.h>
+#include <quick-lint-js/narrow-cast.h>
+#include <quick-lint-js/options.h>
+#include <quick-lint-js/temporary-directory.h>
+#include <string>
+
+namespace quick_lint_js {
+namespace {
+void benchmark_no_config_file(::benchmark::State& state) {
+  int extra_depth = narrow_cast<int>(state.range(0));
+  std::string temp_dir = make_temporary_directory();
+
+  std::string path = temp_dir;
+  for (int i = 0; i < extra_depth; ++i) {
+    path += "/subdir" + std::to_string(i);
+    create_directory(path);
+  }
+  path += "/hello.js";
+  write_file(path, u8"");
+
+  for (auto _ : state) {
+    configuration_loader loader;
+    configuration* config = loader.load_for_file(file_to_lint{
+        .path = path.c_str(),
+        .config_file = nullptr,
+        .is_stdin = false,
+        .vim_bufnr = std::nullopt,
+    });
+    ::benchmark::DoNotOptimize(config);
+  }
+}
+BENCHMARK(benchmark_no_config_file)
+    ->Arg(0)
+    ->Arg(8)
+    ->Arg(16)
+    ->Arg(24)
+    ->Arg(32)
+    ->Arg(48)
+    ->Arg(64);
+}  // namespace
+}  // namespace quick_lint_js
+
+// quick-lint-js finds bugs in JavaScript programs.
+// Copyright (C) 2020  Matthew Glazar
+//
+// This file is part of quick-lint-js.
+//
+// quick-lint-js is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// quick-lint-js is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with quick-lint-js.  If not, see <https://www.gnu.org/licenses/>.

src/CMakeLists.txt

@@ -112,6 +112,7 @@ quick_lint_js_add_library(
   quick-lint-js/parse.h
   quick-lint-js/pipe-reader.h
   quick-lint-js/simd.h
+  quick-lint-js/temporary-directory.h
   quick-lint-js/text-error-reporter.h
   quick-lint-js/translation-data.h
   quick-lint-js/translation.h
@@ -124,6 +125,7 @@ quick_lint_js_add_library(
   quick-lint-js/vim-qflist-json-error-reporter.h
   quick-lint-js/warning.h
   quick-lint-js/web-demo-location.h
+  temporary-directory.cpp
   text-error-reporter.cpp
   translation-data.cpp
   translation.cpp

test/quick-lint-js/temporary-directory.h renamed to src/quick-lint-js/temporary-directory.h

@@ -7,8 +7,14 @@
 #include <string>
 
 namespace quick_lint_js {
+// Crashes on failure.
 std::string make_temporary_directory();
-void delete_directory_recursive(const std::string &path);
+
+// Crashes on failure.
+void create_directory(const std::string& path);
+
+// Crashes on failure.
+void delete_directory_recursive(const std::string& path);
 }
 
 #endif

test/temporary-directory.cpp renamed to src/temporary-directory.cpp

@@ -21,6 +21,10 @@
 #include <filesystem>
 #endif
 
+#if QLJS_HAVE_MKDTEMP
+#include <sys/stat.h>
+#endif
+
 namespace quick_lint_js {
 #if QLJS_HAVE_MKDTEMP
 std::string make_temporary_directory() {
@@ -63,6 +67,18 @@ std::string make_temporary_directory() {
 #error "Unsupported platform"
 #endif
 
+void create_directory(const std::string &path) {
+#if QLJS_HAVE_STD_FILESYSTEM
+  std::filesystem::create_directory(path);
+#else
+  if (::mkdir(path.c_str(), 0755) != 0) {
+    std::fprintf(stderr, "error: failed to create directory %s: %s\n",
+                 path.c_str(), std::strerror(errno));
+    std::terminate();
+  }
+#endif
+}
+
 #if QLJS_HAVE_FTS_H
 void delete_directory_recursive(const std::string &path) {
   char *paths[] = {const_cast<char *>(path.c_str()), nullptr};
@@ -117,7 +133,7 @@ void delete_directory_recursive(const std::string &path) {
   ::fts_close(fts);
 }
 #elif QLJS_HAVE_STD_FILESYSTEM
-void delete_directory_recursive(const std::string &path) {
+void delete_directory_recursive(const std::string& path) {
   std::filesystem::remove_all(std::filesystem::path(path));
 }
 #endif

test/CMakeLists.txt

@@ -21,9 +21,7 @@ quick_lint_js_add_executable(
   quick-lint-js/spy-lsp-endpoint-remote.h
   quick-lint-js/spy-lsp-message-parser.h
   quick-lint-js/spy-visitor.h
-  quick-lint-js/temporary-directory.h
   spy-visitor.cpp
-  temporary-directory.cpp
   test-array.cpp
   test-assert.cpp
   test-bit.cpp

test/test-configuration-loader.cpp

@@ -21,10 +21,6 @@
 #include <filesystem>
 #endif
 
-#if QLJS_HAVE_MKDTEMP
-#include <sys/stat.h>
-#endif
-
 QLJS_WARNING_IGNORE_GCC("-Wmissing-field-initializers")
 
 #define EXPECT_DEFAULT_CONFIG(config)                                  \
@@ -50,18 +46,6 @@ using namespace std::literals::string_view_literals;
 
 namespace quick_lint_js {
 namespace {
-void create_directory(const std::string& path) {
-#if QLJS_HAVE_STD_FILESYSTEM
-  std::filesystem::create_directory(path);
-#else
-  if (::mkdir(path.c_str(), 0755) != 0) {
-    std::fprintf(stderr, "error: failed to create directory %s: %s\n",
-                 path.c_str(), std::strerror(errno));
-    std::terminate();
-  }
-#endif
-}
-
 std::string get_current_working_directory() {
 #if QLJS_HAVE_STD_FILESYSTEM
   return std::filesystem::current_path().string();