LibTimeZone: Remove entirely unused time zone methods

Evaluating third-party alternatives to LibTimeZone will be simpler with
unused functionality removed.

Meta/Lagom/Tools/CodeGenerators/LibTimeZone/GenerateTimeZoneData.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022, Tim Flynn <[email protected]>
+ * Copyright (c) 2022-2024, Tim Flynn <[email protected]>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -63,8 +63,6 @@ struct TimeZoneData {
     HashMap<ByteString, Vector<DaylightSavingsOffset>> dst_offsets;
     Vector<ByteString> dst_offset_names;
 
-    HashMap<ByteString, TimeZone::Location> time_zone_coordinates;
-
     HashMap<ByteString, Vector<size_t>> time_zone_regions;
     Vector<ByteString> time_zone_region_names;
 
@@ -140,29 +138,6 @@ struct AK::Formatter<TimeZone::TimeZoneIdentifier> : Formatter<FormatString> {
     }
 };
 
-template<>
-struct AK::Formatter<TimeZone::Coordinate> : Formatter<FormatString> {
-    ErrorOr<void> format(FormatBuilder& builder, TimeZone::Coordinate const& coordinate)
-    {
-        return Formatter<FormatString>::format(builder,
-            "{{ {}, {}, {} }}"sv,
-            coordinate.degrees,
-            coordinate.minutes,
-            coordinate.seconds);
-    }
-};
-
-template<>
-struct AK::Formatter<TimeZone::Location> : Formatter<FormatString> {
-    ErrorOr<void> format(FormatBuilder& builder, TimeZone::Location const& location)
-    {
-        return Formatter<FormatString>::format(builder,
-            "{{ {}, {} }}"sv,
-            location.latitude,
-            location.longitude);
-    }
-};
-
 static Optional<DateTime> parse_date_time(ReadonlySpan<StringView> segments)
 {
     auto comment_index = find_index(segments.begin(), segments.end(), "#"sv);
@@ -363,35 +338,6 @@ static ErrorOr<void> parse_time_zones(StringView time_zone_path, TimeZoneData& t
 
 static ErrorOr<void> parse_time_zone_coordinates(Core::InputBufferedFile& file, TimeZoneData& time_zone_data)
 {
-    auto parse_coordinate = [](auto coordinate) {
-        VERIFY(coordinate.substring_view(0, 1).is_one_of("+"sv, "-"sv));
-        TimeZone::Coordinate parsed {};
-
-        if (coordinate.length() == 5) {
-            // ±DDMM
-            parsed.degrees = coordinate.substring_view(0, 3).template to_number<int>().value();
-            parsed.minutes = coordinate.substring_view(3).template to_number<int>().value();
-        } else if (coordinate.length() == 6) {
-            // ±DDDMM
-            parsed.degrees = coordinate.substring_view(0, 4).template to_number<int>().value();
-            parsed.minutes = coordinate.substring_view(4).template to_number<int>().value();
-        } else if (coordinate.length() == 7) {
-            // ±DDMMSS
-            parsed.degrees = coordinate.substring_view(0, 3).template to_number<int>().value();
-            parsed.minutes = coordinate.substring_view(3, 2).template to_number<int>().value();
-            parsed.seconds = coordinate.substring_view(5).template to_number<int>().value();
-        } else if (coordinate.length() == 8) {
-            // ±DDDDMMSS
-            parsed.degrees = coordinate.substring_view(0, 4).template to_number<int>().value();
-            parsed.minutes = coordinate.substring_view(4, 2).template to_number<int>().value();
-            parsed.seconds = coordinate.substring_view(6).template to_number<int>().value();
-        } else {
-            VERIFY_NOT_REACHED();
-        }
-
-        return parsed;
-    };
-
     Array<u8, 1024> buffer {};
 
     while (TRY(file.can_read_line())) {
@@ -402,17 +348,10 @@ static ErrorOr<void> parse_time_zone_coordinates(Core::InputBufferedFile& file,
 
         auto segments = line.split_view('\t');
         auto regions = segments[0];
-        auto coordinates = segments[1];
         auto zone = segments[2];
 
         VERIFY(time_zone_data.time_zones.contains(zone));
 
-        auto index = coordinates.find_any_of("+-"sv, StringView::SearchDirection::Backward).value();
-        auto latitude = parse_coordinate(coordinates.substring_view(0, index));
-        auto longitude = parse_coordinate(coordinates.substring_view(index));
-
-        time_zone_data.time_zone_coordinates.set(zone, { latitude, longitude });
-
         TRY(regions.for_each_split_view(',', SplitBehavior::Nothing, [&](auto region) -> ErrorOr<void> {
             auto index = time_zone_data.unique_strings.ensure(zone);
             TRY(time_zone_data.time_zone_regions.ensure(region).try_append(index));
@@ -612,18 +551,6 @@ static constexpr Array<@string_index_type@, @size@> @name@ { {)~~~");
             generator.append(" } };");
         });
 
-    generator.set("size", ByteString::number(time_zone_data.time_zone_names.size()));
-    generator.append(R"~~~(
-static constexpr Array<Location, @size@> s_time_zone_locations { {
-)~~~");
-
-    for (auto const& time_zone : time_zone_data.time_zone_names) {
-        auto location = time_zone_data.time_zone_coordinates.get(time_zone).value_or({});
-
-        generator.append(ByteString::formatted("    {},\n", location));
-    }
-    generator.append("} };\n");
-
     auto append_string_conversions = [&](StringView enum_title, StringView enum_snake, auto const& values, Vector<Alias> const& aliases = {}) -> ErrorOr<void> {
         HashValueMap<ByteString> hashes;
         TRY(hashes.try_ensure_capacity(values.size()));
@@ -647,7 +574,6 @@ static constexpr Array<Location, @size@> s_time_zone_locations { {
     };
 
     TRY(append_string_conversions("TimeZone"sv, "time_zone"sv, time_zone_data.time_zone_names, time_zone_data.time_zone_aliases));
-    TRY(append_string_conversions("DaylightSavingsRule"sv, "daylight_savings_rule"sv, time_zone_data.dst_offset_names));
     TRY(append_string_conversions("Region"sv, "region"sv, time_zone_data.time_zone_region_names));
 
     generator.append(R"~~~(
@@ -745,51 +671,6 @@ Optional<Offset> get_time_zone_offset(TimeZone time_zone, AK::UnixDateTime time)
     return dst_offset;
 }
 
-Optional<Array<NamedOffset, 2>> get_named_time_zone_offsets(TimeZone time_zone, AK::UnixDateTime time)
-{
-    auto const& time_zone_offset = find_time_zone_offset(time_zone, time);
-    Array<NamedOffset, 2> named_offsets;
-
-    auto format_name = [](auto format, auto offset) -> ByteString {
-        if (offset == 0)
-            return decode_string(format).replace("{}"sv, ""sv, ReplaceMode::FirstOnly);
-        return ByteString::formatted(decode_string(format), decode_string(offset));
-    };
-
-    auto set_named_offset = [&](auto& named_offset, auto dst_offset, auto in_dst, auto format, auto offset) {
-        named_offset.seconds = time_zone_offset.offset + dst_offset;
-        named_offset.in_dst = in_dst;
-        named_offset.name = format_name(format, offset);
-    };
-
-    if (time_zone_offset.dst_rule != -1) {
-        auto offsets = find_dst_offsets(time_zone_offset, time);
-        auto in_dst = offsets[1]->offset == 0 ? InDST::No : InDST::Yes;
-
-        set_named_offset(named_offsets[0], offsets[0]->offset, InDST::No, time_zone_offset.standard_format, offsets[0]->format);
-        set_named_offset(named_offsets[1], offsets[1]->offset, in_dst, time_zone_offset.daylight_format, offsets[1]->format);
-    } else {
-        auto in_dst = time_zone_offset.dst_offset == 0 ? InDST::No : InDST::Yes;
-        set_named_offset(named_offsets[0], time_zone_offset.dst_offset, in_dst, time_zone_offset.standard_format, 0);
-        set_named_offset(named_offsets[1], time_zone_offset.dst_offset, in_dst, time_zone_offset.daylight_format, 0);
-    }
-
-    return named_offsets;
-}
-
-Optional<Location> get_time_zone_location(TimeZone time_zone)
-{
-    auto is_valid_coordinate = [](auto const& coordinate) {
-        return (coordinate.degrees != 0) || (coordinate.minutes != 0) || (coordinate.seconds != 0);
-    };
-
-    auto const& location = s_time_zone_locations[to_underlying(time_zone)];
-
-    if (is_valid_coordinate(location.latitude) && is_valid_coordinate(location.longitude))
-        return location;
-    return {};
-}
-
 Vector<StringView> time_zones_in_region(StringView region)
 {
     auto region_value = region_from_string(region);

Tests/LibTimeZone/TestTimeZone.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022, Tim Flynn <[email protected]>
+ * Copyright (c) 2022-2024, Tim Flynn <[email protected]>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -180,35 +180,6 @@ TEST_CASE(get_time_zone_offset_with_dst)
     test_offset("America/Asuncion"sv, 1671453238, offset(-1, 3, 00, 00), Yes); // Monday, December 19, 2022 12:33:58 PM
 }
 
-TEST_CASE(get_named_time_zone_offsets)
-{
-    auto test_named_offsets = [](auto time_zone, i64 time, i64 expected_standard_offset, i64 expected_daylight_offset, auto expected_standard_name, auto expected_daylight_name) {
-        auto actual_offsets = TimeZone::get_named_time_zone_offsets(time_zone, AK::UnixDateTime::from_seconds_since_epoch(time));
-        VERIFY(actual_offsets.has_value());
-
-        EXPECT_EQ(actual_offsets->at(0).seconds, expected_standard_offset);
-        EXPECT_EQ(actual_offsets->at(1).seconds, expected_daylight_offset);
-        EXPECT_EQ(actual_offsets->at(0).name, expected_standard_name);
-        EXPECT_EQ(actual_offsets->at(1).name, expected_daylight_name);
-    };
-
-    test_named_offsets("America/New_York"sv, 1642558528, offset(-1, 5, 00, 00), offset(-1, 4, 00, 00), "EST"sv, "EDT"sv); // Wednesday, January 19, 2022 2:15:28 AM
-    test_named_offsets("UTC"sv, 1642558528, offset(+1, 0, 00, 00), offset(+1, 0, 00, 00), "UTC"sv, "UTC"sv);              // Wednesday, January 19, 2022 2:15:28 AM
-    test_named_offsets("GMT"sv, 1642558528, offset(+1, 0, 00, 00), offset(+1, 0, 00, 00), "GMT"sv, "GMT"sv);              // Wednesday, January 19, 2022 2:15:28 AM
-
-    // Phoenix does not observe DST.
-    test_named_offsets("America/Phoenix"sv, 1642558528, offset(-1, 7, 00, 00), offset(-1, 7, 00, 00), "MST"sv, "MST"sv); // Wednesday, January 19, 2022 2:15:28 AM
-
-    // Moscow's observed DST changed several times in 1919.
-    test_named_offsets("Europe/Moscow"sv, -1609459200, offset(+1, 2, 31, 19), offset(+1, 3, 31, 19), "MSK"sv, "MSD"sv);  // Wednesday, January 1, 1919 12:00:00 AM
-    test_named_offsets("Europe/Moscow"sv, -1596412800, offset(+1, 2, 31, 19), offset(+1, 4, 31, 19), "MSK"sv, "MDST"sv); // Sunday, June 1, 1919 12:00:00 AM
-    test_named_offsets("Europe/Moscow"sv, -1589068800, offset(+1, 3, 00, 00), offset(+1, 4, 00, 00), "MSK"sv, "MSD"sv);  // Monday, August 25, 1919 12:00:00 AM
-
-    // Shanghai's DST rules end in 1991.
-    test_named_offsets("Asia/Shanghai"sv, 694223999, offset(+1, 8, 00, 00), offset(+1, 9, 00, 00), "CST"sv, "CDT"sv); // Tuesday, December 31, 1991 11:59:59 PM
-    test_named_offsets("Asia/Shanghai"sv, 694224000, offset(+1, 8, 00, 00), offset(+1, 8, 00, 00), "CST"sv, "CST"sv); // Wednesday, January 1, 1992 12:00:00 AM
-}
-
 #else
 
 TEST_CASE(time_zone_from_string)

Userland/Libraries/LibTimeZone/TimeZone.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022, Tim Flynn <[email protected]>
+ * Copyright (c) 2022-2024, Tim Flynn <[email protected]>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -8,11 +8,9 @@
 #include <AK/Debug.h>
 #include <AK/ScopeGuard.h>
 #include <LibTimeZone/TimeZone.h>
-#include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <time.h>
 #include <unistd.h>
 
 namespace TimeZone {
@@ -75,7 +73,7 @@ class TimeZoneFile {
     FILE* m_file { nullptr };
 };
 
-StringView system_time_zone()
+static StringView system_time_zone()
 {
     TimeZoneFile time_zone_file("r");
     auto time_zone = time_zone_file.read_time_zone();
@@ -126,16 +124,9 @@ StringView current_time_zone()
         dbgln_if(TIME_ZONE_DEBUG, "Could not read the /etc/localtime link: {}", strerror(errno));
     }
 
-    // Read the system timezone file /etc/timezone
     return system_time_zone();
 }
 
-ErrorOr<void> change_time_zone([[maybe_unused]] StringView time_zone)
-{
-    // Do not even attempt to change the time zone of someone's host machine.
-    return {};
-}
-
 ReadonlySpan<TimeZoneIdentifier> __attribute__((weak)) all_time_zones()
 {
 #if !ENABLE_TIME_ZONE_DATA
@@ -178,9 +169,6 @@ Optional<StringView> canonicalize_time_zone(StringView time_zone)
     return canonical_time_zone;
 }
 
-Optional<DaylightSavingsRule> __attribute__((weak)) daylight_savings_rule_from_string(StringView) { return {}; }
-StringView __attribute__((weak)) daylight_savings_rule_to_string(DaylightSavingsRule) { return {}; }
-
 Optional<Offset> __attribute__((weak)) get_time_zone_offset([[maybe_unused]] TimeZone time_zone, AK::UnixDateTime)
 {
 #if !ENABLE_TIME_ZONE_DATA
@@ -198,36 +186,6 @@ Optional<Offset> get_time_zone_offset(StringView time_zone, AK::UnixDateTime tim
     return {};
 }
 
-Optional<Array<NamedOffset, 2>> __attribute__((weak)) get_named_time_zone_offsets([[maybe_unused]] TimeZone time_zone, AK::UnixDateTime)
-{
-#if !ENABLE_TIME_ZONE_DATA
-    VERIFY(time_zone == TimeZone::UTC);
-
-    NamedOffset utc_offset {};
-    utc_offset.name = "UTC"sv;
-
-    return Array { utc_offset, utc_offset };
-#else
-    return {};
-#endif
-}
-
-Optional<Array<NamedOffset, 2>> get_named_time_zone_offsets(StringView time_zone, AK::UnixDateTime time)
-{
-    if (auto maybe_time_zone = time_zone_from_string(time_zone); maybe_time_zone.has_value())
-        return get_named_time_zone_offsets(*maybe_time_zone, time);
-    return {};
-}
-
-Optional<Location> __attribute__((weak)) get_time_zone_location(TimeZone) { return {}; }
-
-Optional<Location> get_time_zone_location(StringView time_zone)
-{
-    if (auto maybe_time_zone = time_zone_from_string(time_zone); maybe_time_zone.has_value())
-        return get_time_zone_location(*maybe_time_zone);
-    return {};
-}
-
 Optional<Region> __attribute__((weak)) region_from_string(StringView) { return {}; }
 StringView __attribute__((weak)) region_to_string(Region) { return {}; }
 Vector<StringView> __attribute__((weak)) time_zones_in_region(StringView) { return {}; }

Userland/Libraries/LibTimeZone/TimeZone.h

@@ -1,13 +1,11 @@
 /*
- * Copyright (c) 2022, Tim Flynn <[email protected]>
+ * Copyright (c) 2022-2024, Tim Flynn <[email protected]>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
 #pragma once
 
-#include <AK/Array.h>
-#include <AK/ByteString.h>
 #include <AK/Error.h>
 #include <AK/Format.h>
 #include <AK/Optional.h>
@@ -39,47 +37,16 @@ struct Offset {
     InDST in_dst { InDST::No };
 };
 
-struct NamedOffset : public Offset {
-    ByteString name;
-};
-
-struct Coordinate {
-    constexpr float decimal_coordinate() const
-    {
-        return static_cast<float>(degrees) + (static_cast<float>(minutes) / 60.0f) + (static_cast<float>(seconds) / 3'600.0f);
-    }
-
-    i16 degrees { 0 };
-    u8 minutes { 0 };
-    u8 seconds { 0 };
-};
-
-struct Location {
-    Coordinate latitude;
-    Coordinate longitude;
-};
-
-StringView system_time_zone();
 StringView current_time_zone();
-ErrorOr<void> change_time_zone(StringView time_zone);
 ReadonlySpan<TimeZoneIdentifier> all_time_zones();
 
 Optional<TimeZone> time_zone_from_string(StringView time_zone);
 StringView time_zone_to_string(TimeZone time_zone);
 Optional<StringView> canonicalize_time_zone(StringView time_zone);
 
-Optional<DaylightSavingsRule> daylight_savings_rule_from_string(StringView daylight_savings_rule);
-StringView daylight_savings_rule_to_string(DaylightSavingsRule daylight_savings_rule);
-
 Optional<Offset> get_time_zone_offset(TimeZone time_zone, AK::UnixDateTime time);
 Optional<Offset> get_time_zone_offset(StringView time_zone, AK::UnixDateTime time);
 
-Optional<Array<NamedOffset, 2>> get_named_time_zone_offsets(TimeZone time_zone, AK::UnixDateTime time);
-Optional<Array<NamedOffset, 2>> get_named_time_zone_offsets(StringView time_zone, AK::UnixDateTime time);
-
-Optional<Location> get_time_zone_location(TimeZone time_zone);
-Optional<Location> get_time_zone_location(StringView time_zone);
-
 Optional<Region> region_from_string(StringView region);
 StringView region_to_string(Region region);
 Vector<StringView> time_zones_in_region(StringView region);