LibUnicode: Do not assume time zones & meta zones have a 1-to-1 mapping

The generator parses metaZones.json to form a mapping of meta zones to
time zones (AKA "golden zone" in TR-35). This parser errantly assumed
this was a 1-to-1 mapping.

Meta/Lagom/Tools/CodeGenerators/LibUnicode/GenerateUnicodeDateTimeFormat.cpp

@@ -519,7 +519,7 @@ struct UnicodeLocaleData {
     HashMap<String, HourCycleListIndexType> hour_cycles;
     Vector<String> hour_cycle_regions;
 
-    HashMap<String, String> meta_zones;
+    HashMap<String, Vector<String>> meta_zones;
     Vector<String> time_zones { "UTC"sv };
 
     Vector<String> calendars;
@@ -618,11 +618,12 @@ static ErrorOr<void> parse_meta_zones(String core_path, UnicodeLocaleData& local
         auto const& meta_zone = mapping.as_object().get("_other"sv);
         auto const& golden_zone = mapping.as_object().get("_type"sv);
 
-        locale_data.meta_zones.set(meta_zone.as_string(), golden_zone.as_string());
+        auto& golden_zones = locale_data.meta_zones.ensure(meta_zone.as_string());
+        golden_zones.append(golden_zone.as_string());
     });
 
     // UTC does not appear in metaZones.json. Define it for convenience so other parsers don't need to check for its existence.
-    locale_data.meta_zones.set("UTC"sv, "UTC"sv);
+    locale_data.meta_zones.set("UTC"sv, { "UTC"sv });
 
     return {};
 };
@@ -1402,7 +1403,7 @@ static ErrorOr<void> parse_time_zone_names(String locale_time_zone_names_path, U
     time_zone_formats.gmt_zero_format = locale_data.unique_strings.ensure(gmt_zero_format_string.as_string());
 
     auto parse_time_zone = [&](StringView meta_zone, JsonObject const& meta_zone_object) {
-        auto const& golden_zone = locale_data.meta_zones.find(meta_zone)->value;
+        auto const& golden_zones = locale_data.meta_zones.find(meta_zone)->value;
         TimeZone time_zone {};
 
         if (auto long_name = parse_name("long"sv, meta_zone_object); long_name.has_value())
@@ -1410,15 +1411,19 @@ static ErrorOr<void> parse_time_zone_names(String locale_time_zone_names_path, U
         if (auto short_name = parse_name("short"sv, meta_zone_object); short_name.has_value())
             time_zone.short_name = short_name.value();
 
+        for (auto const& golden_zone : golden_zones) {
             auto time_zone_index = locale_data.time_zones.find_first_index(golden_zone).value();
             time_zones[time_zone_index] = locale_data.unique_time_zones.ensure(move(time_zone));
+        }
     };
 
     meta_zone_object.as_object().for_each_member([&](auto const& meta_zone, JsonValue const&) {
-        auto const& golden_zone = locale_data.meta_zones.find(meta_zone)->value;
+        auto const& golden_zones = locale_data.meta_zones.find(meta_zone)->value;
 
+        for (auto const& golden_zone : golden_zones) {
             if (!locale_data.time_zones.contains_slow(golden_zone))
                 locale_data.time_zones.append(golden_zone);
+        }
     });
 
     time_zones.resize(locale_data.time_zones.size());

Tests/LibUnicode/CMakeLists.txt

@@ -1,5 +1,6 @@
 set(TEST_SOURCES
     TestUnicodeCharacterTypes.cpp
+    TestUnicodeDateTimeFormat.cpp
     TestUnicodeLocale.cpp
 )
 

Tests/LibUnicode/TestUnicodeDateTimeFormat.cpp

@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2022, Tim Flynn <trflynn89@pm.me>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibTest/TestCase.h>
+
+#include <AK/Array.h>
+#include <AK/StringView.h>
+#include <LibUnicode/DateTimeFormat.h>
+
+TEST_CASE(time_zone_name)
+{
+    struct TestData {
+        StringView locale;
+        Unicode::CalendarPatternStyle style;
+        StringView time_zone;
+        StringView expected_result;
+    };
+
+    constexpr auto test_data = Array {
+        TestData { "en"sv, Unicode::CalendarPatternStyle::Long, "UTC"sv, "Coordinated Universal Time"sv },
+        TestData { "en"sv, Unicode::CalendarPatternStyle::Short, "UTC"sv, "UTC"sv },
+        TestData { "en"sv, Unicode::CalendarPatternStyle::ShortOffset, "UTC"sv, "GMT"sv },
+        TestData { "en"sv, Unicode::CalendarPatternStyle::LongOffset, "UTC"sv, "GMT"sv },
+        TestData { "en"sv, Unicode::CalendarPatternStyle::ShortGeneric, "UTC"sv, "GMT"sv },
+        TestData { "en"sv, Unicode::CalendarPatternStyle::LongGeneric, "UTC"sv, "GMT"sv },
+
+        TestData { "ar"sv, Unicode::CalendarPatternStyle::Long, "UTC"sv, "التوقيت العالمي المنسق"sv },
+        TestData { "ar"sv, Unicode::CalendarPatternStyle::Short, "UTC"sv, "UTC"sv },
+        TestData { "ar"sv, Unicode::CalendarPatternStyle::ShortOffset, "UTC"sv, "غرينتش"sv },
+        TestData { "ar"sv, Unicode::CalendarPatternStyle::LongOffset, "UTC"sv, "غرينتش"sv },
+        TestData { "ar"sv, Unicode::CalendarPatternStyle::ShortGeneric, "UTC"sv, "غرينتش"sv },
+        TestData { "ar"sv, Unicode::CalendarPatternStyle::LongGeneric, "UTC"sv, "غرينتش"sv },
+
+        TestData { "en"sv, Unicode::CalendarPatternStyle::Long, "America/Los_Angeles"sv, "Pacific Daylight Time"sv },
+        TestData { "en"sv, Unicode::CalendarPatternStyle::Short, "America/Los_Angeles"sv, "PDT"sv },
+
+        TestData { "ar"sv, Unicode::CalendarPatternStyle::Long, "America/Los_Angeles"sv, "توقيت المحيط الهادي الصيفي"sv },
+        // The "ar" locale does not have a short name for PDT. LibUnicode will need to fall back to GMT offset when we have that data.
+
+        TestData { "en"sv, Unicode::CalendarPatternStyle::Long, "America/Vancouver"sv, "Pacific Daylight Time"sv },
+        TestData { "en"sv, Unicode::CalendarPatternStyle::Short, "America/Vancouver"sv, "PDT"sv },
+
+        TestData { "ar"sv, Unicode::CalendarPatternStyle::Long, "America/Vancouver"sv, "توقيت المحيط الهادي الصيفي"sv },
+        // The "ar" locale does not have a short name for PDT. LibUnicode will need to fall back to GMT offset when we have that data.
+
+        TestData { "en"sv, Unicode::CalendarPatternStyle::Long, "Europe/London"sv, "Greenwich Mean Time"sv },
+        TestData { "en"sv, Unicode::CalendarPatternStyle::Short, "Europe/London"sv, "GMT"sv },
+
+        TestData { "ar"sv, Unicode::CalendarPatternStyle::Long, "Europe/London"sv, "توقيت غرينتش"sv },
+        // The "ar" locale does not have a short name for GMT. LibUnicode will need to fall back to GMT offset when we have that data.
+
+        TestData { "en"sv, Unicode::CalendarPatternStyle::Long, "Africa/Accra"sv, "Greenwich Mean Time"sv },
+        TestData { "en"sv, Unicode::CalendarPatternStyle::Short, "Africa/Accra"sv, "GMT"sv },
+
+        TestData { "ar"sv, Unicode::CalendarPatternStyle::Long, "Africa/Accra"sv, "توقيت غرينتش"sv },
+        // The "ar" locale does not have a short name for GMT. LibUnicode will need to fall back to GMT offset when we have that data.
+    };
+
+    for (auto const& test : test_data) {
+        auto time_zone = Unicode::get_time_zone_name(test.locale, test.time_zone, test.style);
+        VERIFY(time_zone.has_value());
+        EXPECT_EQ(*time_zone, test.expected_result);
+    }
+}

Userland/Libraries/LibUnicode/Forward.h

@@ -35,7 +35,7 @@ enum class ScriptTag : u8;
 enum class StandardNumberFormatType : u8;
 enum class Style : u8;
 enum class Territory : u8;
-enum class TimeZone : u8;
+enum class TimeZone : u16;
 enum class Weekday : u8;
 enum class WordBreakProperty : u8;