Bulletproofing for PESEL numbers containing other characters than digits

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## v0.2.0
+
+ * fix ArgumentError when passing broken PESEL containing not only digits
+
 ## v0.1.0
 
-* here it begins
+ * here it begins

README.md

@@ -58,7 +58,7 @@ to your list of dependencies in `mix.exs`:
 ```elixir
 def deps do
   [
-    {:ex_pesel, "~> 0.1.0"}
+    {:ex_pesel, "~> 0.2.0"}
   ]
 end
 ```

lib/ex_pesel.ex

@@ -46,6 +46,9 @@ defmodule ExPesel do
 
       iex> ExPesel.valid?("23455532312131123123")
       false
+
+      iex> ExPesel.valid?("some really bad data")
+      false
   """
   @spec valid?(String.t()) :: boolean()
   defdelegate valid?(pesel), to: Pesel
@@ -75,6 +78,9 @@ defmodule ExPesel do
 
       iex> ExPesel.valid_with?("44051401458", {1944, 6, 13})
       false
+
+      iex> ExPesel.valid_with?("some really bad data", {1944, 6, 13})
+      false
   """
   def valid_with?(pesel, sex_or_birthday)
 
@@ -115,8 +121,11 @@ defmodule ExPesel do
 
       iex> ExPesel.birthdate("90720312611")
       {2290, 12, 3}
+
+      iex> ExPesel.birthdate("some really bad input")
+      :unknown
   """
-  @spec birthdate(String.t()) :: {1800..2299, 1..12, 1..31}
+  @spec birthdate(String.t()) :: {1800..2299, 1..12, 1..31} | :unknown
   defdelegate birthdate(pesel), to: Pesel
 
   @doc """
@@ -132,8 +141,11 @@ defmodule ExPesel do
 
       iex> ExPesel.sex("88122302080")
       :female
+
+      iex> ExPesel.sex("some bad input")
+      :unknown
   """
-  @spec sex(String.t()) :: :male | :female
+  @spec sex(String.t()) :: :male | :female | :unknown
   defdelegate sex(pesel), to: Pesel
 
   @doc """
@@ -147,6 +159,9 @@ defmodule ExPesel do
 
       iex> ExPesel.zombie?("88122302080")
       false
+
+      iex> ExPesel.zombie?("I'm a zombie man!")
+      false
   """
   @spec zombie?(String.t()) :: boolean()
   defdelegate zombie?(pesel), to: Pesel

lib/ex_pesel/pesel.ex

@@ -48,7 +48,7 @@ defmodule ExPesel.Pesel do
   # for 2000-2099 we got addition of 20 to mm
   # for 2100-2199 we got addition of 40 to mm
   # for 2200-2299 we got addition of 60 to mm
-  @spec birthdate(String.t()) :: {1800..2299, 1..12, 1..3}
+  @spec birthdate(String.t()) :: {1800..2299, 1..12, 1..3} | :unknown
   def birthdate(pesel), do: do_birthdate(to_list(pesel))
 
   # sorry for that but in elixir there is no multiguards
@@ -67,6 +67,8 @@ defmodule ExPesel.Pesel do
   defp do_birthdate([y1, y2, m1, m2, d1, d2 | _])
   when m1 < 10, do: date({18, y1, y2}, {m1 - 8, m2}, {d1, d2})
 
+  defp do_birthdate([]), do: :unknown
+
   defp date(as_year, as_month, as_day) do
     {year(as_year), month(as_month), day(as_day)}
   end
@@ -78,24 +80,33 @@ defmodule ExPesel.Pesel do
   # Sex is encoded with 10 digit
   # odd for male
   # even for female
-  @spec sex(String.t()) :: :male | :female
+  @spec sex(String.t()) :: :male | :female | :unknown
   def sex(pesel) when is_binary(pesel), do: do_sex(to_list(pesel))
 
   defp do_sex([_, _, _, _, _, _, _, _, _, s | _]) when rem(s, 2) == 1, do: :male
-  defp do_sex(_), do: :female
+  defp do_sex([]), do: :unknown
+  defp do_sex(_),  do: :female
 
   # PESEL is zombie if
   # date of birth is 123 years before today
   @spec zombie?(String.t()) :: boolean()
   def zombie?(pesel) when is_binary(pesel), do: is_zombie?(pesel)
 
-  defp is_zombie?(pesel), do: birthdate(pesel) < years_before(today(), @years)
+  defp is_zombie?(pesel), do: dead?(birthdate(pesel))
+  defp dead?(:unknown), do: false
+  defp dead?(birthday), do: birthday < years_before(today(), @years)
   defp years_before({year, month, day}, dist), do: {year - dist, month, day}
 
   # Transpose from string to list
   defp to_list(pesel) do
     pesel
+    |> scan()
+    |> resolve()
     |> String.split("", trim: true)
     |> Enum.map(&String.to_integer/1)
   end
+
+  defp scan(pesel), do: Regex.scan(~r/^\d{11}$/, pesel)
+  defp resolve([]),         do: ""
+  defp resolve([[pesel]]),  do: pesel
 end

mix.exs

@@ -1,7 +1,7 @@
 defmodule ExPesel.MixProject do
   use Mix.Project
 
-  @version "0.1.0"
+  @version "0.2.0"
 
   @description "Library for PESEL number."
   @repo_url "https://github.com/crabonature/ex_pesel"