4 structs shouldnt implement outstanding by default

README.md

@@ -224,6 +224,16 @@ Once we've created a backup child we want to keep track of it, so we refine the
 
 An application using outstanding would update expected, then do work based on what is outstanding given actual.Outstanding can be further processed (by your code) to detemine next action based on your priority of goals not met, constraints, business rules, etc. 
 
+## Acknowledgements
+
+Thanks to Ilja Tkachuk for [comparable](https://github.com/coingaming/comparable) which was an exemplar.
+
+Kudos to the [Elixir Core Team](https://elixir-lang.org/) for [elixir] https://github.com/elixir-lang/elixir 🚀
+
+## Links
+[Diffo.dev] (https://www.diffo.dev))
+[`Ash Outstanding` docs](https://hexdocs.pm/ash_outstanding).
+
 Documentation can be generated with [ExDoc](https://github.com/elixir-lang/ex_doc)
 and published on [HexDocs](https://hexdocs.pm). Once published, the docs can
 be found at <https://hexdocs.pm/outstanding>.

lib/outstand.ex

@@ -1394,6 +1394,8 @@ defmodule Outstand do
   DateTime
   iex> Outstand.type_of(~D[2025-02-25])
   Date
+  iex> Outstand.type_of(self())
+  Other
   ```
   """
   @spec type_of(any()) :: module()
@@ -1414,7 +1416,7 @@ defmodule Outstand do
           is_list(term)                        -> List
           is_map(term)                         -> Map
           is_tuple(term)                       -> Tuple
-          true                                 -> Any
+          true                                 -> Other
         end
     end
   end

lib/outstanding.ex

@@ -3,7 +3,7 @@ defprotocol Outstanding do
   @moduledoc """
   Protocol for comparing expected and actual, highlighting outstanding expectations unmet by actual
   """
-  @fallback_to_any true
+  @fallback_to_any false
   @type t :: Outstanding.t()
   @type result :: nil | Outstanding.t()
 

lib/outstanding/date.ex

@@ -0,0 +1,14 @@
+use Outstand
+
+defoutstanding expected :: Date, actual :: Any do
+  if expected == nil or Outstand.type_of(actual) != Date do
+    expected
+  else
+    case Date.compare(expected, actual) do
+      :eq ->
+        nil
+      _ ->
+        expected
+    end
+  end
+end

lib/outstanding/date_time.ex

@@ -0,0 +1,14 @@
+use Outstand
+
+defoutstanding expected :: DateTime, actual :: Any do
+  if expected == nil or Outstand.type_of(actual) != DateTime do
+    expected
+  else
+    case DateTime.compare(expected, actual) do
+      :eq ->
+        nil
+      _ ->
+        expected
+    end
+  end
+end

lib/outstanding/naive_date_time.ex

@@ -0,0 +1,14 @@
+use Outstand
+
+defoutstanding expected :: NaiveDateTime, actual :: Any do
+  if expected == nil or Outstand.type_of(actual) != NaiveDateTime do
+    expected
+  else
+    case NaiveDateTime.compare(expected, actual) do
+      :eq ->
+        nil
+      _ ->
+        expected
+    end
+  end
+end

lib/outstanding/time.ex

@@ -0,0 +1,14 @@
+use Outstand
+
+defoutstanding expected :: Time, actual :: Any do
+  if expected == nil or Outstand.type_of(actual) != Time do
+    expected
+  else
+    case Time.compare(expected, actual) do
+      :eq ->
+        nil
+      _ ->
+        expected
+    end
+  end
+end

mix.exs

@@ -11,18 +11,18 @@ defmodule Outstanding.MixProject do
       deps: deps(),
       # ex_doc
       name: "Outstanding",
-      source_url: "https://github.com/matt-beanland/outstanding",
+      source_url: "https://github.com/diffo-dev/outstanding",
       homepage_url: "https://diffo.dev/diffo/outstanding",
       docs: [main: "readme", extras: ["README.md"]],
       # hex.pm stuff
-      description: "Outstanding (a.k.a extent expected realised by actual) Elixir protocol",
+      description: "Elixir protocol calculating outstanding from expected and actual",
       package: [
         licenses: ["MIT"],
         files: ["lib", "mix.exs", "README*", "VERSION*"],
         maintainers: ["Matt Beanland"],
         links: %{
-          "GitHub" => "https://github.com/matt-beanland/outstanding",
-          "Author's home page" => "https://diffo.dev"
+          "GitHub" => "https://github.com/diffo-dev/outstanding",
+          "Author's home page" => "https://www.diffo.dev"
         }
       ]
     ]

test/date_test.exs

@@ -0,0 +1,16 @@
+defmodule Outstanding.DateTest do
+  use ExUnit.Case
+  use Outstand
+
+  @now DateTime.utc_now() |> DateTime.to_naive()
+  @future DateTime.utc_now() |> DateTime.add(1, :day)|> DateTime.to_date()
+  @past DateTime.utc_now() |> DateTime.add(-1, :day) |> DateTime.to_date()
+
+  gen_something_outstanding_test("value outstanding, future", @now, @future)
+  gen_something_outstanding_test("value outstanding, past", @now, @past)
+  gen_something_outstanding_test("value outstanding, nil", @now, nil)
+  gen_nothing_outstanding_test("realized", @now, @now)
+  gen_result_outstanding_test("value result, future", @now, @future, @now)
+  gen_result_outstanding_test("value result, past", @now, @past, @now)
+  gen_result_outstanding_test("value result, nil", @now, nil, @now)
+end

test/date_time_test.exs

@@ -0,0 +1,16 @@
+defmodule Outstanding.DateTimeTest do
+  use ExUnit.Case
+  use Outstand
+
+  @now DateTime.utc_now()
+  @future DateTime.utc_now() |> DateTime.add(1, :day)
+  @past DateTime.utc_now() |> DateTime.add(-1, :day)
+
+  gen_something_outstanding_test("value outstanding, future", @now, @future)
+  gen_something_outstanding_test("value outstanding, past", @now, @past)
+  gen_something_outstanding_test("value outstanding, nil", @now, nil)
+  gen_nothing_outstanding_test("realized", @now, @now)
+  gen_result_outstanding_test("value result, future", @now, @future, @now)
+  gen_result_outstanding_test("value result, past", @now, @past, @now)
+  gen_result_outstanding_test("value result, nil", @now, nil, @now)
+end

test/naive_date_time_test.exs

@@ -0,0 +1,16 @@
+defmodule Outstanding.NaiveDateTimeTest do
+  use ExUnit.Case
+  use Outstand
+
+  @now DateTime.utc_now() |> DateTime.to_naive()
+  @future DateTime.utc_now() |> DateTime.add(1, :day)|> DateTime.to_naive()
+  @past DateTime.utc_now() |> DateTime.add(-1, :day) |> DateTime.to_naive()
+
+  gen_something_outstanding_test("value outstanding, future", @now, @future)
+  gen_something_outstanding_test("value outstanding, past", @now, @past)
+  gen_something_outstanding_test("value outstanding, nil", @now, nil)
+  gen_nothing_outstanding_test("realized", @now, @now)
+  gen_result_outstanding_test("value result, future", @now, @future, @now)
+  gen_result_outstanding_test("value result, past", @now, @past, @now)
+  gen_result_outstanding_test("value result, nil", @now, nil, @now)
+end

test/struct_test.exs

@@ -0,0 +1,38 @@
+defmodule Outstanding.StructTest do
+  use ExUnit.Case
+  use Outstand
+
+  @v0 :value0
+  @v1 :value1
+  @v2 :value2
+
+  defmodule XYZ do
+    defstruct [:x, :y, :z]
+  end
+
+  defoutstanding expected :: XYZ, actual :: Any do
+    case {expected, actual} do
+      {nil, nil} ->
+        nil
+      {_, ^expected} ->
+        nil
+      {%name{}, %name{}} ->
+        expected
+        |> Map.from_struct()
+        |> Outstanding.outstanding(Map.from_struct(actual))
+        |> Outstand.map_to_struct(name)
+      {_, _} ->
+        # not an exact match so default to outstanding
+        expected
+    end
+  end
+
+  gen_something_outstanding_test("key outstanding", %XYZ{x: @v0, y: @v1}, %XYZ{x: @v0, z: @v1})
+  gen_something_outstanding_test("value outstanding", %XYZ{x: @v0, y: @v1, z: @v2}, %XYZ{x: @v1, y: @v1, z: @v2})
+  gen_nothing_outstanding_test("realized", %XYZ{x: @v0, y: @v1, z: @v2}, %XYZ{x: @v0, y: @v1, z: @v2})
+  gen_nothing_outstanding_test("realized, no z expectation", %XYZ{x: @v0, y: @v1}, %XYZ{x: @v0, y: @v1})
+  gen_nothing_outstanding_test("realized, nil z expectation", %XYZ{x: @v0, y: @v1, z: nil}, %XYZ{x: @v0, y: @v1})
+  gen_nothing_outstanding_test("realized, extra item", %XYZ{x: @v0, y: @v1}, %XYZ{x: @v0, y: @v1, z: @v1})
+  gen_result_outstanding_test("key result", %XYZ{x: @v0, y: @v1}, %XYZ{x: @v0, z: @v1}, %XYZ{y: @v1})
+  gen_result_outstanding_test("value result", %XYZ{x: @v0, y: @v1}, %XYZ{x: @v1, y: @v1}, %XYZ{x: @v0})
+end

test/time_test.exs

@@ -0,0 +1,16 @@
+defmodule Outstanding.TimeTest do
+  use ExUnit.Case
+  use Outstand
+
+  @now DateTime.utc_now() |> DateTime.to_time()
+  @future DateTime.utc_now() |> DateTime.add(1, :hour)|> DateTime.to_time()
+  @past DateTime.utc_now() |> DateTime.add(-1, :hour) |> DateTime.to_time()
+
+  gen_something_outstanding_test("value outstanding, future", @now, @future)
+  gen_something_outstanding_test("value outstanding, past", @now, @past)
+  gen_something_outstanding_test("value outstanding, nil", @now, nil)
+  gen_nothing_outstanding_test("realized", @now, @now)
+  gen_result_outstanding_test("value result, future", @now, @future, @now)
+  gen_result_outstanding_test("value result, past", @now, @past, @now)
+  gen_result_outstanding_test("value result, nil", @now, nil, @now)
+end