changes Erlang date tuples to Elixir Date structs

README.md

@@ -29,15 +29,15 @@ Add holidays to your list of dependencies in `mix.exs`:
 3.  Call the `on` function, passing in a date and a list of regions.
 
     ```
-    iex> Holidays.on({2016, 1, 1}, [:us])
+    iex> Holidays.on(~D[2016-01-01], [:us])
     [%{name: "New Year's Day"}]
     ```
 
 The `on` function gives a list of holidays for a date within
 specified regions.
 
-Dates in Erlang (and therefore Elixir) are represented by the
-`{year, month, day}` tuple.
+Dates in Elixir are represented by the
+`~D[yyyy-mm-dd]` sigil.
 
 Regions are often country codes, like `:us` or `:ca`, but
 may also be entities such as UPS (`:ups`) or the New York Stock Exchange

lib/holidays.ex

@@ -25,11 +25,11 @@ defmodule Holidays do
 
   ## Examples
 
-      iex> Holidays.on({2016, 1, 1}, [:us])
+      iex> Holidays.on(~D[2016-01-01], [:us])
       [%{name: "New Year's Day"}]
 
   """
-  @spec on(:calendar.date(), [region]) :: list
+  @spec on(Calendar.date(), [region]) :: list
   def on(date, regions) do
     Holidays.Define.on(date, regions)
   end

lib/holidays/date_calculator/date_math.ex

@@ -1,55 +1,38 @@
 defmodule Holidays.DateCalculator.DateMath do
-  @doc """
-  Adds the given number of `days` to the given `date`.
-
-  ## Examples
-
-      iex> Holidays.DateCalculator.DateMath.add_days({2015, 12, 31}, 1)
-      {2016, 1, 1}
-
-      iex> Holidays.DateCalculator.DateMath.add_days({2016, 1, 6}, -12)
-      {2015, 12, 25}
-
-  """
-  @spec add_days(:calendar.date(), integer) :: :calendar.date()
-  def add_days(date, days) do
-    :calendar.gregorian_days_to_date(:calendar.date_to_gregorian_days(date) + days)
-  end
-
   @offset %{:first => 1, :second => 8, :third => 15, :fourth => 22}
 
   @doc """
   Returns the date for the `week`th `weekday` for the given `year` and `month`.
 
   `week` may be one of :first, :second, :third, :fourth, :last
 
-  `weekday` may be a number between 1 and 7, which is the way Erlang
+  `weekday` may be a number between 1 and 7, which is the way Elixir
   represents Monday through Sunday. Or use one the atoms
   :monday, :tuesday, :wednesday, :thursday, :friday, :saturday, :sunday
 
   ## Examples
 
       # The second Tuesday of June, 2013
       iex> Holidays.DateCalculator.DateMath.get_weekth_day(2013, 6, :second, :tuesday)
-      {2013, 6, 11}
+      ~D[2013-06-11]
 
       # The third Friday of December, 2013
       iex> Holidays.DateCalculator.DateMath.get_weekth_day(2013, 12, :third, :friday)
-      {2013, 12, 20}
+      ~D[2013-12-20]
 
       # The last Saturday of January, 2013
       iex> Holidays.DateCalculator.DateMath.get_weekth_day(2013, 1, :last, :saturday)
-      {2013, 1, 26}
+      ~D[2013-01-26]
 
   """
   @spec get_weekth_day(
           pos_integer,
           pos_integer,
           Holidays.week(),
           Holidays.weekday() | pos_integer
-        ) :: :calendar.date()
+        ) :: Date.t()
   def get_weekth_day(year, month, :last, weekday) do
-    offset = :calendar.last_day_of_the_month(year, month) - 6
+    offset = Date.days_in_month(Date.new!(year, month, 1)) - 6
     do_get_weekth_day(year, month, offset, weekday)
   end
 
@@ -68,22 +51,23 @@ defmodule Holidays.DateCalculator.DateMath do
   }
 
   @spec do_get_weekth_day(pos_integer, pos_integer, pos_integer, Holidays.weekday() | pos_integer) ::
-          :calendar.date()
+          Date.t()
   defp do_get_weekth_day(year, month, offset, weekday) when not is_integer(weekday) do
     do_get_weekth_day(year, month, offset, @daynum[weekday])
   end
 
   defp do_get_weekth_day(year, month, offset, weekday) do
-    day = weekday - :calendar.day_of_the_week(year, month, offset) + offset
+    date = Date.new!(year, month, offset)
+    day = weekday - Date.day_of_week(date) + offset
     correct_offset(year, month, offset, day)
   end
 
-  @spec correct_offset(pos_integer, pos_integer, pos_integer, integer) :: :calendar.date()
+  @spec correct_offset(pos_integer, pos_integer, pos_integer, integer) :: Date.t()
   defp correct_offset(year, month, offset, day) when day < offset do
-    {year, month, day + 7}
+    Date.new!(year, month, day + 7)
   end
 
-  defp correct_offset(year, month, _offset, day), do: {year, month, day}
+  defp correct_offset(year, month, _offset, day), do: Date.new!(year, month, day)
 
   @dayname %{
     1 => :monday,
@@ -103,22 +87,22 @@ defmodule Holidays.DateCalculator.DateMath do
 
   ## Examples
 
-      iex> Holidays.DateCalculator.DateMath.get_week_and_weekday({2016,1,29})
+      iex> Holidays.DateCalculator.DateMath.get_week_and_weekday(~D[2016-01-29])
       [{:last, :friday}]
 
-      iex> Holidays.DateCalculator.DateMath.get_week_and_weekday({2016,1,25})
+      iex> Holidays.DateCalculator.DateMath.get_week_and_weekday(~D[2016-01-25])
       [{:fourth, :monday}, {:last, :monday}]
 
-      iex> Holidays.DateCalculator.DateMath.get_week_and_weekday({2016,1,5})
+      iex> Holidays.DateCalculator.DateMath.get_week_and_weekday(~D[2016-01-05])
       [{:first, :tuesday}]
   """
-  @spec get_week_and_weekday(:calendar.date()) :: [{Holidays.week(), Holidays.weekday()}]
-  def get_week_and_weekday({year, month, day} = date) do
-    day_name = @dayname[:calendar.day_of_the_week(date)]
+  @spec get_week_and_weekday(Date.t()) :: [{Holidays.week(), Holidays.weekday()}]
+  def get_week_and_weekday(%Date{day: day} = date) do
+    day_name = @dayname[Date.day_of_week(date)]
 
     week_name(div(day - 1, 7), day_name) ++
       check_last_week(
-        :calendar.last_day_of_the_month(year, month) - day,
+        Date.days_in_month(date) - day,
         day_name
       )
   end

lib/holidays/date_calculator/easter.ex

@@ -1,16 +1,14 @@
 defmodule Holidays.DateCalculator.Easter do
-  alias Holidays.DateCalculator.DateMath
-
   @doc ~S"""
   Returns the date of Easter for the given `year`
 
   ## Examples
 
       iex> Holidays.DateCalculator.Easter.gregorian_easter_for(2016)
-      {2016, 3, 27}
+      ~D[2016-03-27]
 
       iex> Holidays.DateCalculator.Easter.gregorian_easter_for(2015)
-      {2015, 4, 5}
+      ~D[2015-04-05]
 
   """
   def gregorian_easter_for(year) do
@@ -31,23 +29,22 @@ defmodule Holidays.DateCalculator.Easter do
     month = (h + l - 7 * m + 114) |> div(31)
     day = ((h + l - 7 * m + 114) |> rem(31)) + 1
 
-    {year, month, day}
+    Date.new!(year, month, day)
   end
 
   @doc ~S"""
-
   Returns the date of Orthodox Easter in the given `year`
 
   ## Examples
 
       iex> Holidays.DateCalculator.Easter.gregorian_orthodox_easter_for(2016)
-      {2016, 5, 1}
+      ~D[2016-05-01]
 
       iex> Holidays.DateCalculator.Easter.gregorian_orthodox_easter_for(1815)
-      {1815, 4, 30}
+      ~D[1815-04-30]
 
       iex> Holidays.DateCalculator.Easter.gregorian_orthodox_easter_for(2101)
-      {2101, 4, 24}
+      ~D[2101-04-24]
 
   """
   def gregorian_orthodox_easter_for(year) do
@@ -69,7 +66,7 @@ defmodule Holidays.DateCalculator.Easter do
           0
       end
 
-    DateMath.add_days(j_date, offset)
+    Date.add(j_date, offset)
   end
 
   def julian_orthodox_easter_for(year) do
@@ -80,6 +77,6 @@ defmodule Holidays.DateCalculator.Easter do
     j_month = 3 + div(i - j + 40, 44)
     j_day = i - j + 28 - 31 * div(j_month, 4)
 
-    {year, j_month, j_day}
+    Date.new!(year, j_month, j_day)
   end
 end

lib/holidays/date_calculator/weekend_modifier.ex

@@ -1,25 +1,23 @@
 defmodule Holidays.DateCalculator.WeekendModifier do
-  alias Holidays.DateCalculator.DateMath
-
   @doc """
   Move `date` to Monday if it occurs on a Saturday or Sunday.
 
   ## Examples
 
-      iex> Holidays.DateCalculator.WeekendModifier.to_monday_if_weekend({2015,12,5})
-      {2015,12,7}
+      iex> Holidays.DateCalculator.WeekendModifier.to_monday_if_weekend(~D[2015-12-05])
+      ~D[2015-12-07]
 
-      iex> Holidays.DateCalculator.WeekendModifier.to_monday_if_weekend({2015,12,6})
-      {2015,12,7}
+      iex> Holidays.DateCalculator.WeekendModifier.to_monday_if_weekend(~D[2015-12-06])
+      ~D[2015-12-07]
 
-      iex> Holidays.DateCalculator.WeekendModifier.to_monday_if_weekend({2015,12,8})
-      {2015,12,8}
+      iex> Holidays.DateCalculator.WeekendModifier.to_monday_if_weekend(~D[2015-12-08])
+      ~D[2015-12-08]
 
   """
   def to_monday_if_weekend(date) do
-    case :calendar.day_of_the_week(date) do
-      7 -> DateMath.add_days(date, 1)
-      6 -> DateMath.add_days(date, 2)
+    case Date.day_of_week(date) do
+      6 -> Date.add(date, 2)
+      7 -> Date.add(date, 1)
       _ -> date
     end
   end
@@ -29,19 +27,19 @@ defmodule Holidays.DateCalculator.WeekendModifier do
 
   ## Examples
 
-      iex> Holidays.DateCalculator.WeekendModifier.to_monday_if_sunday({2015,12,5})
-      {2015,12,5}
+      iex> Holidays.DateCalculator.WeekendModifier.to_monday_if_sunday(~D[2015-12-05])
+      ~D[2015-12-05]
 
-      iex> Holidays.DateCalculator.WeekendModifier.to_monday_if_sunday({2015,12,6})
-      {2015,12,7}
+      iex> Holidays.DateCalculator.WeekendModifier.to_monday_if_sunday(~D[2015-12-06])
+      ~D[2015-12-07]
 
-      iex> Holidays.DateCalculator.WeekendModifier.to_monday_if_sunday({2015,12,8})
-      {2015,12,8}
+      iex> Holidays.DateCalculator.WeekendModifier.to_monday_if_sunday(~D[2015-12-08])
+      ~D[2015-12-08]
 
   """
   def to_monday_if_sunday(date) do
-    case :calendar.day_of_the_week(date) do
-      7 -> DateMath.add_days(date, 1)
+    case Date.day_of_week(date) do
+      7 -> Date.add(date, 1)
       _ -> date
     end
   end
@@ -56,20 +54,20 @@ defmodule Holidays.DateCalculator.WeekendModifier do
 
   ## Examples
 
-      iex> Holidays.DateCalculator.WeekendModifier.to_weekday_if_weekend({2015,12,5})
-      {2015,12,4}
+      iex> Holidays.DateCalculator.WeekendModifier.to_weekday_if_weekend(~D[2015-12-05])
+      ~D[2015-12-04]
 
-      iex> Holidays.DateCalculator.WeekendModifier.to_weekday_if_weekend({2015,12,6})
-      {2015,12,7}
+      iex> Holidays.DateCalculator.WeekendModifier.to_weekday_if_weekend(~D[2015-12-06])
+      ~D[2015-12-07]
 
-      iex> Holidays.DateCalculator.WeekendModifier.to_weekday_if_weekend({2015,12,8})
-      {2015,12,8}
+      iex> Holidays.DateCalculator.WeekendModifier.to_weekday_if_weekend(~D[2015-12-08])
+      ~D[2015-12-08]
 
   """
   def to_weekday_if_weekend(date) do
-    case :calendar.day_of_the_week(date) do
-      7 -> DateMath.add_days(date, 1)
-      6 -> DateMath.add_days(date, -1)
+    case Date.day_of_week(date) do
+      7 -> Date.add(date, 1)
+      6 -> Date.add(date, -1)
       _ -> date
     end
   end

lib/holidays/define.ex

@@ -19,7 +19,7 @@ defmodule Holidays.Define do
     GenServer.cast(__MODULE__, {:add_entry, :fun, {name, function, regions}})
   end
 
-  @spec on(:calendar.date(), [Holidays.region()]) :: list
+  @spec on(Date.t(), [Holidays.region()]) :: list
   def on(date, regions) do
     GenServer.call(__MODULE__, {:on, date, regions})
   end
@@ -30,7 +30,7 @@ defmodule Holidays.Define do
       on_fun(funs, date)
   end
 
-  defp on_static(holidays, {_, month, day}) do
+  defp on_static(holidays, %Date{month: month, day: day}) do
     holidays
     |> Enum.filter(fn
       {_, ^month, ^day, _} -> true
@@ -44,7 +44,7 @@ defmodule Holidays.Define do
     |> Enum.flat_map(&on_nth(&1, holidays, date))
   end
 
-  defp on_nth({week, weekday}, holidays, {_, month, _}) do
+  defp on_nth({week, weekday}, holidays, %Date{month: month}) do
     holidays
     |> Enum.filter(&match?({_, ^month, ^week, ^weekday, _}, &1))
     |> Enum.map(fn {name, _, _, _, regions} -> %{name: name, regions: regions} end)
@@ -58,10 +58,10 @@ defmodule Holidays.Define do
 
   defp apply_fun({mod, fun, args, days}, date) do
     apply_fun({mod, fun, args}, date)
-    |> DateMath.add_days(days)
+    |> Date.add(days)
   end
 
-  defp apply_fun({mod, fun, [:year]}, {year, _, _}) do
+  defp apply_fun({mod, fun, [:year]}, %Date{year: year}) do
     apply(mod, fun, [year])
   end
 

lib/holidays/definitions/br.ex

@@ -95,7 +95,7 @@ defmodule Holidays.Definitions.Br do
       :none
 
       iex> Holidays.Definitions.Br.election_day(2018)
-      {2018, 10, 7}
+      ~D[2018-10-07]
   """
   def election_day(year) when rem(year, 4) == 2,
     do: DateMath.get_weekth_day(year, 10, :first, :sunday)

lib/holidays/definitions/de.ex

@@ -117,12 +117,16 @@ defmodule Holidays.Definitions.De do
   end
 
   def buss_und_bettag(year) do
-    wday = rem(:calendar.day_of_the_week(year, 11, 23), 7)
+    wday =
+      year
+      |> Date.new!(11, 23)
+      |> Date.day_of_week()
+      |> rem(7)
 
     if wday > 3 do
-      {year, 11, 23 - (wday - 3)}
+      Date.new!(year, 11, 23 - (wday - 3))
     else
-      {year, 11, 23 - (wday + 4)}
+      Date.new!(year, 11, 23 - (wday + 4))
     end
   end
 end

lib/holidays/definitions/us.ex

@@ -101,16 +101,16 @@ defmodule Holidays.Definitions.Us do
       :none
 
       iex> Holidays.Definitions.Us.inauguration_day(2017)
-      {2017, 1, 20}
+      ~D[2017-01-20]
 
       iex> Holidays.Definitions.Us.inauguration_day(2018)
       :none
   """
-  def inauguration_day(year) when rem(year, 4) == 1, do: {year, 1, 20}
+  def inauguration_day(year) when rem(year, 4) == 1, do: Date.new!(year, 1, 20)
   def inauguration_day(_year), do: :none
 
   def day_after_thanksgiving(year) do
     DateMath.get_weekth_day(year, 11, :fourth, :thursday)
-    |> DateMath.add_days(1)
+    |> Date.add(1)
   end
 end