Remove legacy decode option before release (#10)

In order to simplify the code and future maintenance do not support a legacy option in decode.

Migrating legacy ShortUUID to the new format is a simple as reversing the string so better not add debt to support it.

CHANGELOG.md

@@ -5,8 +5,24 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
 
-## v3.0.0
+## v3.0.0 (15.07.2023)
+
+Breaking change, ShortUUIDs created by `< v3.0.0` will produce bad results when decoded.
+The new output of `encode` is the reverse of the previous output.
+This follows a change in other languages ShortUUID libraries.
+
+To migrate ShortUUIDs created by `< v3.0.0` reverse them before passing to `decode`.
+
+```elixir
+# UUID "00000001-0001-0001-0001-000000000001" encoded using v2.1.2 to "UD6ibhr3V4YXvriP822222"
+# reversing the encoded string before decode with v3.0.0 will produce the correct result
+iex> "UD6ibhr3V4YXvriP822222" |> String.reverse() |> ShortUUID.decode!()
+"00000001-0001-0001-0001-000000000001"
+```
+
+### Changed
 * move most significant bit to the beginning of the encoded result similar to libraries in other languages (most importantly python shortuuid)
 * drop support for decoding of un-padded ShortUUIDs
 * drop support for formats other than regular hyphenated and unhyphenated UUIDs, MS format and binary UUIDs like are stored in PostgreSQL uuid type
@@ -15,13 +31,21 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Benchmarks
 Results are not comparable to previous benchmarks due to them being run on a different system
-
-Operating System: macOS
-CPU Information: Apple M2 Max
-Number of Available Cores: 12
-Available memory: 32 GB
-Elixir 1.15.2
-Erlang 25.3.2.3
+  ```
+  Operating System: macOS
+  CPU Information: Apple M2 Max
+  Number of Available Cores: 12
+  Available memory: 32 GB
+  Elixir 1.15.2
+  Erlang 25.3.2.3
+
+  Benchmark suite executing with the following configuration:
+  warmup: 2 s
+  time: 5 s
+  memory time: 0 ns
+  parallel: 1
+  inputs: none specified
+  ```
 
 * v3.0.0
   ```

README.md

@@ -43,18 +43,16 @@ iex> "00000001-0001-0001-0001-000000000001" |> ShortUUID.encode
 
 ```
 
-To decode ShortUUID created with version < v3.0.0 use one of two methods
+To migrate ShortUUIDs created using `< v3.0.0` reverse them before passing to `decode`.
 
 ```elixir
-iex> "UD6ibhr3V4YXvriP822222" |> String.reverse() |> ShortUUID.decode()
-{:ok, "00000001-0001-0001-0001-000000000001"}
-
-iex> "UD6ibhr3V4YXvriP822222" |> ShortUUID.decode(legacy: true)
-{:ok, "00000001-0001-0001-0001-000000000001"}
-
+# UUID "00000001-0001-0001-0001-000000000001" encoded using v2.1.2 to "UD6ibhr3V4YXvriP822222"
+# reversing the encoded string before decode with v3.0.0 will produce the correct result
+iex> "UD6ibhr3V4YXvriP822222" |> String.reverse() |> ShortUUID.decode!()
+"00000001-0001-0001-0001-000000000001"
 ```
 
-Decoding legacy ShortUUIDs without either reversing the string first or using the legacy option will not fail but produce an incorrect result
+*Warning:* Decoding ShortUUIDs created using a version `< v3.0.0` without reversing the string first will not fail but produce an incorrect result
 
 ```elixir
 iex> "UD6ibhr3V4YXvriP822222" |> ShortUUID.decode!() === "00000001-0001-0001-0001-000000000001"
@@ -70,7 +68,7 @@ Add `:shortuuid` to your list of dependencies in `mix.exs`:
 ```elixir
 def deps do
   [
-    {:shortuuid, "~> 2.0"}
+    {:shortuuid, "~> 3.0"}
   ]
 end
 ```

lib/shortuuid.ex

@@ -122,13 +122,10 @@ defmodule ShortUUID do
   @doc """
   Decodes a ShortUUID string into a UUID.
   """
-  @spec decode(String.t(), keyword()) :: {:ok, String.t()} | {:error, String.t()}
-  def decode(shortuuid, opts \\ [legacy: false])
-
+  @spec decode(String.t()) :: {:ok, String.t()} | {:error, String.t()}
   def decode(
         <<c1::8, c2::8, c3::8, c4::8, c5::8, c6::8, c7::8, c8::8, c9::8, c10::8, c11::8, c12::8,
-          c13::8, c14::8, c15::8, c16::8, c17::8, c18::8, c19::8, c20::8, c21::8, c22::8>>,
-        legacy: false
+          c13::8, c14::8, c15::8, c16::8, c17::8, c18::8, c19::8, c20::8, c21::8, c22::8>>
       ) do
     uuid_int_value =
       [
@@ -178,19 +175,7 @@ defmodule ShortUUID do
       {:error, "Invalid input"}
   end
 
-  def decode(
-        <<c1::8, c2::8, c3::8, c4::8, c5::8, c6::8, c7::8, c8::8, c9::8, c10::8, c11::8, c12::8,
-          c13::8, c14::8, c15::8, c16::8, c17::8, c18::8, c19::8, c20::8, c21::8, c22::8>>,
-        legacy: true
-      ) do
-    decode(
-      <<c22, c21, c20, c19, c18, c17, c16, c15, c14, c13, c12, c11, c10, c9, c8, c7, c6, c5, c4,
-        c3, c2, c1>>,
-      legacy: false
-    )
-  end
-
-  def decode(_string, _opts) do
+  def decode(_string) do
     {:error, "Invalid input"}
   end
 
@@ -199,9 +184,9 @@ defmodule ShortUUID do
 
   Raises an ArgumentError if the ShortUUID is invalid.
   """
-  @spec decode!(String.t(), keyword()) :: String.t() | no_return()
-  def decode!(string, opts \\ [legacy: false]) do
-    case decode(string, opts) do
+  @spec decode!(String.t()) :: String.t() | no_return()
+  def decode!(string) do
+    case decode(string) do
       {:ok, uuid} -> uuid
       {:error, message} -> raise ArgumentError, message: message
     end

test/shortuuid_test.exs

@@ -118,7 +118,7 @@ defmodule ShortUUIDTest do
     end
   end
 
-  describe "decode/2" do
+  describe "decode/1" do
     test "decodes a valid shortuuid" do
       assert {:ok, "2a162ee5-02f4-4701-9e87-72762cbce5e2"} =
                ShortUUID.decode("9VprZJ9U7Tgg2PJ8BfTAek")
@@ -177,18 +177,13 @@ defmodule ShortUUIDTest do
       assert {:error, _} = ShortUUID.decode(false)
     end
 
-    test "decodes legacy shortuuid" do
-      assert {:ok, "2a162ee5-02f4-4701-9e87-72762cbce5e2"} =
-               ShortUUID.decode("keATfB8JP2ggT7U9JZrpV9", legacy: true)
+    test "reversed legacy short UUID will produce correct result" do
+      assert {:ok, "00000001-0001-0001-0001-000000000001"} =
+               "UD6ibhr3V4YXvriP822222" |> String.reverse() |> ShortUUID.decode()
     end
   end
 
-  describe "decode!/2" do
-    test "decodes legacy shortuuid" do
-      assert "2a162ee5-02f4-4701-9e87-72762cbce5e2" =
-               ShortUUID.decode!("keATfB8JP2ggT7U9JZrpV9", legacy: true)
-    end
-
+  describe "decode!/1" do
     test "raises an ArgumentError for and invalid ShortUUID" do
       assert_raise ArgumentError, fn ->
         ShortUUID.decode!("invalid-shortuuid")