[llvm-branch-commits] [libcxx] [libc++][chrono] Loads leap-seconds.list in tzdb. (PR #82113)

[Louis Dionne via llvm-branch-commits]

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@@ -0,0 +1,102 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17
+// UNSUPPORTED: no-filesystem, no-localization, no-tzdb
+
+// XFAIL: libcpp-has-no-incomplete-tzdb
+// XFAIL: availability-tzdb-missing
+
+// <chrono>
+
+// Tests the IANA database leap seconds parsing and operations.
+// This is not part of the public tzdb interface.
+
+#include <cassert>
+#include <chrono>
+#include <fstream>
+#include <string>
+#include <string_view>
+
+#include "assert_macros.h"
+#include "concat_macros.h"
+#include "filesystem_test_helper.h"
+#include "test_tzdb.h"
+
+scoped_test_env env;
+[[maybe_unused]] const std::filesystem::path dir = env.create_dir("zoneinfo");
+const std::filesystem::path tzdata               = env.create_file("zoneinfo/tzdata.zi");
+const std::filesystem::path leap_seconds         = env.create_file("zoneinfo/leap-seconds.list");
+
+std::string_view std::chrono::__libcpp_tzdb_directory() {
+  static std::string result = dir.string();
+  return result;
+}
+
+void write(std::string_view input) {
+  static int version = 0;
+
+  std::ofstream f{tzdata};
+  f << "# version " << version++ << '\n';
+  std::ofstream{leap_seconds}.write(input.data(), input.size());
+}
+
+static const std::chrono::tzdb& parse(std::string_view input) {
+  write(input);
+  return std::chrono::reload_tzdb();
+}
+
+static void test_exception(std::string_view input, [[maybe_unused]] std::string_view what) {
+  write(input);
+
+  TEST_VALIDATE_EXCEPTION(
+      std::runtime_error,
+      [&]([[maybe_unused]] const std::runtime_error& e) {
+        TEST_LIBCPP_REQUIRE(
+            e.what() == what,
+            TEST_WRITE_CONCATENATED("\nExpected exception ", what, "\nActual exception   ", e.what(), '\n'));
+      },
+      TEST_IGNORE_NODISCARD std::chrono::reload_tzdb());
+}
+
+static void test_invalid() {
+  test_exception("0", "corrupt tzdb: expected a non-zero digit");
+
+  test_exception("1", "corrupt tzdb: expected whitespace");
+
+  test_exception("1 ", "corrupt tzdb: expected a non-zero digit");
+}
+
+static void test_leap_seconds() {
+  using namespace std::chrono;
+
+  const tzdb& result = parse(
+      R"(
+2272060800  10  # 1 Jan 1972
+2287785600  11  # 1 Jul 1972
+2303683200  12  # 1 Jan 1973
----------------
ldionne wrote:

You could provide them unordered to test the sorting logic.

Also, what about testing a date before 1970?

https://github.com/llvm/llvm-project/pull/82113