[Beam] Implement missing DateTimeOffset members, add DateOnly and TimeOnly (#4479)

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: dbrattli

src/Fable.Cli/CHANGELOG.md

@@ -12,6 +12,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 * [All] Add support for `Guid.CreateVersion7()` and `Guid.CreateVersion7(DateTimeOffset)`
 * [Rust] Add missing `System.Random` implementation and tests (by @ncave)
 * [Rust] Add missing `Array`, `List` and `Seq` module members and tests: `randomChoice`, `randomChoiceBy`, `randomChoiceWith`, `randomChoices`, `randomChoicesBy`, `randomChoicesWith`, `randomSample`, `randomSampleBy`, `randomSampleWith`, `randomShuffle`, `randomShuffleBy`, `randomShuffleWith` (by @ncave)
+* [Beam] Implement missing DateTimeOffset members, add DateOnly and TimeOnly support
 
 ### Fixed
 

src/Fable.Compiler/CHANGELOG.md

@@ -12,6 +12,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 * [All] Add support for `Guid.CreateVersion7()` and `Guid.CreateVersion7(DateTimeOffset)`
 * [Rust] Add missing `System.Random` implementation and tests (by @ncave)
 * [Rust] Add missing `Array`, `List` and `Seq` module members and tests: `randomChoice`, `randomChoiceBy`, `randomChoiceWith`, `randomChoices`, `randomChoicesBy`, `randomChoicesWith`, `randomSample`, `randomSampleBy`, `randomSampleWith`, `randomShuffle`, `randomShuffleBy`, `randomShuffleWith` (by @ncave)
+* [Beam] Implement missing DateTimeOffset members, add DateOnly and TimeOnly support
 
 ### Fixed
 

src/Fable.Transforms/Beam/Replacements.fs

@@ -3,49 +3,114 @@
     create/7, create/8,
     from_date/2,
     from_ticks/2,
+    from_date_time/3,
     year/1,
     month/1,
     day/1,
     hour/1,
     minute/1,
     second/1,
     millisecond/1,
+    microsecond/1,
     ticks/1,
     offset/1,
     date_time/1,
+    date/1,
+    time_of_day/1,
+    day_of_week/1,
+    day_of_year/1,
+    total_offset_minutes/1,
+    utc_ticks/1,
     now/0,
     utc_now/0,
     min_value/0,
+    max_value/0,
+    unix_epoch/0,
+    local_date_time/1,
+    utc_date_time/1,
     to_local_time/1,
     to_universal_time/1,
+    to_offset/2,
+    add/2,
+    subtract/2,
+    add_years/2,
+    add_months/2,
+    add_days/2,
+    add_hours/2,
+    add_minutes/2,
+    add_seconds/2,
+    add_milliseconds/2,
+    add_ticks/2,
+    op_addition/2,
+    op_subtraction/2,
+    compare/2,
+    equals/2,
+    equals_exact/2,
+    from_unix_time_seconds/1,
+    from_unix_time_milliseconds/1,
+    to_unix_time_seconds/1,
+    to_unix_time_milliseconds/1,
     try_parse/2,
     to_string/1, to_string/2, to_string/3
 ]).
 
 -type datetimeoffset() :: {integer(), 0 | 1 | 2, integer()}.
+-type datetime() :: {integer(), 0 | 1 | 2}.
 
 -spec create(integer(), integer(), integer(), integer(), integer(), integer(), integer()) ->
     datetimeoffset().
 -spec create(
     integer(), integer(), integer(), integer(), integer(), integer(), integer(), integer()
 ) -> datetimeoffset().
--spec from_date({integer(), integer()}, integer()) -> datetimeoffset().
+-spec from_date(datetime(), integer()) -> datetimeoffset().
 -spec from_ticks(integer(), integer()) -> datetimeoffset().
+-spec from_date_time(datetime(), integer(), integer()) -> datetimeoffset().
 -spec year(datetimeoffset()) -> integer().
 -spec month(datetimeoffset()) -> integer().
 -spec day(datetimeoffset()) -> integer().
 -spec hour(datetimeoffset()) -> integer().
 -spec minute(datetimeoffset()) -> integer().
 -spec second(datetimeoffset()) -> integer().
 -spec millisecond(datetimeoffset()) -> integer().
+-spec microsecond(datetimeoffset()) -> integer().
 -spec ticks(datetimeoffset()) -> integer().
 -spec offset(datetimeoffset()) -> integer().
--spec date_time(datetimeoffset()) -> {integer(), integer()}.
+-spec date_time(datetimeoffset()) -> datetime().
+-spec date(datetimeoffset()) -> datetime().
+-spec time_of_day(datetimeoffset()) -> integer().
+-spec day_of_week(datetimeoffset()) -> integer().
+-spec day_of_year(datetimeoffset()) -> integer().
+-spec total_offset_minutes(datetimeoffset()) -> integer().
+-spec utc_ticks(datetimeoffset()) -> integer().
 -spec now() -> datetimeoffset().
 -spec utc_now() -> datetimeoffset().
 -spec min_value() -> datetimeoffset().
+-spec max_value() -> datetimeoffset().
+-spec unix_epoch() -> datetimeoffset().
+-spec local_date_time(datetimeoffset()) -> datetime().
+-spec utc_date_time(datetimeoffset()) -> datetime().
 -spec to_local_time(datetimeoffset()) -> datetimeoffset().
 -spec to_universal_time(datetimeoffset()) -> datetimeoffset().
+-spec to_offset(datetimeoffset(), integer()) -> datetimeoffset().
+-spec add(datetimeoffset(), integer()) -> datetimeoffset().
+-spec subtract(datetimeoffset(), datetimeoffset() | integer()) -> datetimeoffset() | integer().
+-spec add_years(datetimeoffset(), integer()) -> datetimeoffset().
+-spec add_months(datetimeoffset(), integer()) -> datetimeoffset().
+-spec add_days(datetimeoffset(), number()) -> datetimeoffset().
+-spec add_hours(datetimeoffset(), number()) -> datetimeoffset().
+-spec add_minutes(datetimeoffset(), number()) -> datetimeoffset().
+-spec add_seconds(datetimeoffset(), number()) -> datetimeoffset().
+-spec add_milliseconds(datetimeoffset(), number()) -> datetimeoffset().
+-spec add_ticks(datetimeoffset(), integer()) -> datetimeoffset().
+-spec op_addition(datetimeoffset(), integer()) -> datetimeoffset().
+-spec op_subtraction(datetimeoffset(), datetimeoffset() | integer()) -> datetimeoffset() | integer().
+-spec compare(datetimeoffset(), datetimeoffset()) -> -1 | 0 | 1.
+-spec equals(datetimeoffset(), datetimeoffset()) -> boolean().
+-spec equals_exact(datetimeoffset(), datetimeoffset()) -> boolean().
+-spec from_unix_time_seconds(integer()) -> datetimeoffset().
+-spec from_unix_time_milliseconds(integer()) -> datetimeoffset().
+-spec to_unix_time_seconds(datetimeoffset()) -> integer().
+-spec to_unix_time_milliseconds(datetimeoffset()) -> integer().
 -spec try_parse(binary(), reference()) -> boolean().
 -spec to_string(datetimeoffset()) -> binary().
 -spec to_string(datetimeoffset(), binary()) -> binary().
@@ -55,14 +120,15 @@
 %% - Ticks: same as DateTime (100-ns intervals from Jan 1, 0001)
 %% - Kind: 0=Unspecified, 1=UTC, 2=Local
 %% - OffsetTicks: offset from UTC as TimeSpan ticks
-%%
-%% For most property access, we delegate to fable_date since the
-%% underlying datetime components are the same.
 
 -define(TICKS_PER_MILLISECOND, 10000).
 -define(TICKS_PER_SECOND, 10000000).
 -define(TICKS_PER_MINUTE, 600000000).
 -define(TICKS_PER_HOUR, 36000000000).
+-define(TICKS_PER_DAY, 864000000000).
+
+%% .NET epoch offset: ticks from 0001-01-01 to 1970-01-01
+-define(UNIX_EPOCH_TICKS, 621355968000000000).
 
 %% ============================================================
 %% Constructors
@@ -72,24 +138,14 @@
 create(Y, M, D, H, Min, S, OffsetTicks) when is_integer(OffsetTicks) ->
     DT = fable_date:create(Y, M, D, H, Min, S),
     {Ticks, _Kind} = DT,
-    Kind =
-        case OffsetTicks of
-            % UTC
-            0 -> 1;
-            % Unspecified
-            _ -> 0
-        end,
+    Kind = offset_to_kind(OffsetTicks),
     {Ticks, Kind, OffsetTicks}.
 
 %% create(Y, M, D, H, Min, S, Ms, OffsetTimeSpan)
 create(Y, M, D, H, Min, S, Ms, OffsetTicks) when is_integer(OffsetTicks) ->
     DT = fable_date:create(Y, M, D, H, Min, S, Ms),
     {Ticks, _Kind} = DT,
-    Kind =
-        case OffsetTicks of
-            0 -> 1;
-            _ -> 0
-        end,
+    Kind = offset_to_kind(OffsetTicks),
     {Ticks, Kind, OffsetTicks}.
 
 %% from_date(DateTime, OffsetTimeSpan)
@@ -98,13 +154,19 @@ from_date({Ticks, Kind}, OffsetTicks) ->
 
 %% from_ticks(Ticks, OffsetTimeSpan)
 from_ticks(Ticks, OffsetTicks) ->
-    Kind =
-        case OffsetTicks of
-            0 -> 1;
-            _ -> 0
-        end,
+    Kind = offset_to_kind(OffsetTicks),
     {Ticks, Kind, OffsetTicks}.
 
+%% from_date_time(DateOnly, TimeOnlyTicks, OffsetTimeSpan)
+%% DateOnly is {DayTicks, Kind}, TimeOnly is ticks since midnight
+from_date_time({DayTicks, _Kind}, TimeOnlyTicks, OffsetTicks) ->
+    Ticks = DayTicks + TimeOnlyTicks,
+    Kind = offset_to_kind(OffsetTicks),
+    {Ticks, Kind, OffsetTicks}.
+
+offset_to_kind(0) -> 1;  % UTC
+offset_to_kind(_) -> 0.  % Unspecified
+
 %% ============================================================
 %% Properties (delegate to fable_date)
 %% ============================================================
@@ -116,6 +178,7 @@ hour({Ticks, Kind, _Offset}) -> fable_date:hour({Ticks, Kind}).
 minute({Ticks, Kind, _Offset}) -> fable_date:minute({Ticks, Kind}).
 second({Ticks, Kind, _Offset}) -> fable_date:second({Ticks, Kind}).
 millisecond({Ticks, Kind, _Offset}) -> fable_date:millisecond({Ticks, Kind}).
+microsecond({Ticks, Kind, _Offset}) -> fable_date:microsecond({Ticks, Kind}).
 ticks({Ticks, _Kind, _Offset}) -> Ticks.
 
 %% Offset returns the TimeSpan offset (ticks)
@@ -124,30 +187,161 @@ offset({_Ticks, _Kind, OffsetTicks}) -> OffsetTicks.
 %% DateTime property: returns a DateTime {Ticks, Kind=Unspecified}
 date_time({Ticks, _Kind, _Offset}) -> {Ticks, 0}.
 
+%% Date property: returns DateTime with time zeroed
+date({Ticks, Kind, _Offset}) -> fable_date:date({Ticks, Kind}).
+
+%% TimeOfDay: returns TimeSpan (ticks) of the time-of-day component
+time_of_day({Ticks, _Kind, _Offset}) ->
+    Ticks rem ?TICKS_PER_DAY.
+
+%% DayOfWeek
+day_of_week({Ticks, Kind, _Offset}) -> fable_date:day_of_week({Ticks, Kind}).
+
+%% DayOfYear
+day_of_year({Ticks, Kind, _Offset}) -> fable_date:day_of_year({Ticks, Kind}).
+
+%% TotalOffsetMinutes
+total_offset_minutes({_Ticks, _Kind, OffsetTicks}) ->
+    OffsetTicks div ?TICKS_PER_MINUTE.
+
+%% UtcTicks: Ticks adjusted by offset
+utc_ticks({Ticks, _Kind, OffsetTicks}) ->
+    Ticks - OffsetTicks.
+
 %% ============================================================
 %% Static methods
 %% ============================================================
 
 now() ->
     {Ticks, _Kind} = fable_date:now(),
-    {Ticks, 2, 0}.
+    OffsetTicks = local_offset_ticks(),
+    {Ticks, 2, OffsetTicks}.
 
 utc_now() ->
     {Ticks, _Kind} = fable_date:utc_now(),
     {Ticks, 1, 0}.
 
 min_value() -> {0, 0, 0}.
 
+max_value() -> {3155378975999999999, 0, 0}.
+
+unix_epoch() ->
+    {?UNIX_EPOCH_TICKS, 1, 0}.
+
 %% ============================================================
 %% Conversion
 %% ============================================================
 
-to_local_time({Ticks, _Kind, _Offset}) ->
-    {Ticks, 2, 0}.
+to_local_time({Ticks, _Kind, OffsetTicks}) ->
+    %% Convert to UTC ticks, then to local
+    UtcTicks = Ticks - OffsetTicks,
+    LocalOffset = local_offset_ticks(),
+    {UtcTicks + LocalOffset, 2, LocalOffset}.
 
 to_universal_time({Ticks, _Kind, OffsetTicks}) ->
     {Ticks - OffsetTicks, 1, 0}.
 
+to_offset({Ticks, _Kind, OffsetTicks}, NewOffsetTicks) ->
+    %% Convert to UTC, then apply new offset
+    UtcTicks = Ticks - OffsetTicks,
+    Kind = offset_to_kind(NewOffsetTicks),
+    {UtcTicks + NewOffsetTicks, Kind, NewOffsetTicks}.
+
+local_date_time({Ticks, _Kind, OffsetTicks}) ->
+    UtcTicks = Ticks - OffsetTicks,
+    LocalOffset = local_offset_ticks(),
+    {UtcTicks + LocalOffset, 2}.
+
+utc_date_time({Ticks, _Kind, OffsetTicks}) ->
+    {Ticks - OffsetTicks, 1}.
+
+%% ============================================================
+%% Arithmetic
+%% ============================================================
+
+add({Ticks, Kind, OffsetTicks}, TimeSpanTicks) ->
+    {Ticks + TimeSpanTicks, Kind, OffsetTicks}.
+
+subtract({Ticks1, _Kind1, Offset1}, {Ticks2, _Kind2, Offset2}) ->
+    %% DTO - DTO -> TimeSpan (compare UTC instants)
+    (Ticks1 - Offset1) - (Ticks2 - Offset2);
+subtract({Ticks, Kind, OffsetTicks}, TimeSpanTicks) when is_integer(TimeSpanTicks) ->
+    {Ticks - TimeSpanTicks, Kind, OffsetTicks}.
+
+add_years({Ticks, Kind, OffsetTicks}, Years) ->
+    {NewTicks, _} = fable_date:add_years({Ticks, Kind}, Years),
+    {NewTicks, Kind, OffsetTicks}.
+
+add_months({Ticks, Kind, OffsetTicks}, Months) ->
+    {NewTicks, _} = fable_date:add_months({Ticks, Kind}, Months),
+    {NewTicks, Kind, OffsetTicks}.
+
+add_days({Ticks, Kind, OffsetTicks}, Days) ->
+    Added = trunc(Days * ?TICKS_PER_DAY),
+    {Ticks + Added, Kind, OffsetTicks}.
+
+add_hours({Ticks, Kind, OffsetTicks}, Hours) ->
+    Added = trunc(Hours * ?TICKS_PER_HOUR),
+    {Ticks + Added, Kind, OffsetTicks}.
+
+add_minutes({Ticks, Kind, OffsetTicks}, Minutes) ->
+    Added = trunc(Minutes * ?TICKS_PER_MINUTE),
+    {Ticks + Added, Kind, OffsetTicks}.
+
+add_seconds({Ticks, Kind, OffsetTicks}, Seconds) ->
+    Added = trunc(Seconds * ?TICKS_PER_SECOND),
+    {Ticks + Added, Kind, OffsetTicks}.
+
+add_milliseconds({Ticks, Kind, OffsetTicks}, Milliseconds) ->
+    Added = trunc(Milliseconds * ?TICKS_PER_MILLISECOND),
+    {Ticks + Added, Kind, OffsetTicks}.
+
+add_ticks({Ticks, Kind, OffsetTicks}, AddedTicks) ->
+    {Ticks + AddedTicks, Kind, OffsetTicks}.
+
+op_addition(DTO, TimeSpanTicks) -> add(DTO, TimeSpanTicks).
+op_subtraction(DTO, Other) -> subtract(DTO, Other).
+
+%% ============================================================
+%% Comparison / Equality
+%% ============================================================
+
+%% Compare by UTC instant
+compare({Ticks1, _Kind1, Offset1}, {Ticks2, _Kind2, Offset2}) ->
+    Utc1 = Ticks1 - Offset1,
+    Utc2 = Ticks2 - Offset2,
+    if
+        Utc1 < Utc2 -> -1;
+        Utc1 > Utc2 -> 1;
+        true -> 0
+    end.
+
+equals({Ticks1, _Kind1, Offset1}, {Ticks2, _Kind2, Offset2}) ->
+    (Ticks1 - Offset1) =:= (Ticks2 - Offset2).
+
+equals_exact({Ticks1, _Kind1, Offset1}, {Ticks2, _Kind2, Offset2}) ->
+    (Ticks1 - Offset1) =:= (Ticks2 - Offset2) andalso Offset1 =:= Offset2.
+
+%% ============================================================
+%% Unix time
+%% ============================================================
+
+from_unix_time_seconds(Seconds) ->
+    Ticks = ?UNIX_EPOCH_TICKS + Seconds * ?TICKS_PER_SECOND,
+    {Ticks, 1, 0}.
+
+from_unix_time_milliseconds(Ms) ->
+    Ticks = ?UNIX_EPOCH_TICKS + Ms * ?TICKS_PER_MILLISECOND,
+    {Ticks, 1, 0}.
+
+to_unix_time_seconds({Ticks, _Kind, OffsetTicks}) ->
+    UtcTicks = Ticks - OffsetTicks,
+    (UtcTicks - ?UNIX_EPOCH_TICKS) div ?TICKS_PER_SECOND.
+
+to_unix_time_milliseconds({Ticks, _Kind, OffsetTicks}) ->
+    UtcTicks = Ticks - OffsetTicks,
+    (UtcTicks - ?UNIX_EPOCH_TICKS) div ?TICKS_PER_MILLISECOND.
+
 %% ============================================================
 %% TryParse
 %% ============================================================
@@ -196,3 +390,19 @@ format_offset(OffsetTicks) ->
     H = AbsTicks div ?TICKS_PER_HOUR,
     M = (AbsTicks rem ?TICKS_PER_HOUR) div ?TICKS_PER_MINUTE,
     iolist_to_binary(io_lib:format("~s~2..0B:~2..0B", [Sign, H, M])).
+
+%% ============================================================
+%% Internal helpers
+%% ============================================================
+
+local_offset_ticks() ->
+    %% Get local offset from UTC in ticks
+    UtcSecs = erlang:system_time(second),
+    {{UY,UM,UD},{UH,UMin,US}} = calendar:now_to_universal_time({UtcSecs div 1000000, UtcSecs rem 1000000, 0}),
+    {{LY,LM,LD},{LH,LMin,LS}} = calendar:now_to_local_time({UtcSecs div 1000000, UtcSecs rem 1000000, 0}),
+    UtcDays = calendar:date_to_gregorian_days({UY, UM, UD}),
+    LocalDays = calendar:date_to_gregorian_days({LY, LM, LD}),
+    UtcSecsOfDay = UH * 3600 + UMin * 60 + US,
+    LocalSecsOfDay = LH * 3600 + LMin * 60 + LS,
+    DiffSecs = (LocalDays - UtcDays) * 86400 + (LocalSecsOfDay - UtcSecsOfDay),
+    DiffSecs * ?TICKS_PER_SECOND.