Finished step two: equipment

lib/zombie_survivor/survivor.ex

@@ -3,10 +3,11 @@ defmodule ZombieSurvivor.Survivor do
 
   @type t :: %__MODULE__{
           name: String.t(),
-          wounds: non_neg_integer
+          wounds: non_neg_integer,
+          equipment: [String.t()]
         }
 
-  defstruct name: "", wounds: 0
+  defstruct name: "", wounds: 0, equipment: []
 
   @spec new([{atom, any}]) :: Survivor.t()
   def new(opts \\ []), do: struct(__MODULE__, opts)
@@ -18,4 +19,33 @@ defmodule ZombieSurvivor.Survivor do
   def max_actions(_survivor) do
     3
   end
+
+  @spec wound(Survivor.t(), non_neg_integer) :: Survivor.t()
+  def wound(survivor, num \\ 1) do
+    %{survivor | wounds: survivor.wounds + num}
+    |> discard_equipment()
+  end
+
+  @spec max_equipment(Survivor.t()) :: non_neg_integer
+  def max_equipment(%Survivor{} = survivor) do
+    5 - survivor.wounds
+  end
+
+  @spec add_equipment(Survivor.t(), String.t() | [String.t()]) :: Survivor.t()
+  def add_equipment(%Survivor{equipment: equipment} = survivor, new_items)
+      when is_list(new_items) do
+    %{survivor | equipment: Enum.concat(new_items, equipment)}
+    |> discard_equipment()
+  end
+
+  def add_equipment(%Survivor{equipment: equipment} = survivor, new_item) do
+    %{survivor | equipment: [new_item | equipment]}
+    |> discard_equipment()
+  end
+
+  @spec discard_equipment(Survivor.t()) :: Survivor.t()
+  def discard_equipment(%Survivor{equipment: equipment} = survivor) do
+    max = max_equipment(survivor)
+    %{survivor | equipment: Enum.take(equipment, max)}
+  end
 end

test/survivor_test.exs

@@ -4,6 +4,8 @@ defmodule SurvivorTest do
 
   import Survivor
 
+  @items ["Baseball bat", "Frying pan", "Katana", "Pistol", "Bottled Water", "Molotov"]
+
   describe "new" do
     test "gives a survivor with a name" do
       assert %Survivor{name: _} = Survivor.new()
@@ -39,4 +41,60 @@ defmodule SurvivorTest do
       assert Survivor.max_actions(s) == 3
     end
   end
+
+  describe "max_equipment/1" do
+    test "returns 5 for a new survivor" do
+      assert 5 == max_equipment(Survivor.new())
+    end
+
+    test "returns fewer items with more wounds" do
+      s =
+        Survivor.new()
+        |> Survivor.wound()
+
+      assert max_equipment(s) == 4
+    end
+  end
+
+  describe "wound/1" do
+    # TODO: Property testing with increments
+    test "adds wounds to survivors (duh)" do
+      s =
+        Survivor.new()
+        |> wound()
+
+      assert %{wounds: 1} = s
+    end
+
+    test "drops survivor equipment if they are carrying too much" do
+      # TODO: Property testing
+      # kinda funky if max_equipment rules change, will fix later
+      s =
+        Survivor.new()
+        |> add_equipment(@items)
+
+      max = max_equipment(s)
+      assert max == length(s.equipment)
+
+      s =
+        s
+        |> wound
+
+      assert max - 1 == length(s.equipment)
+    end
+
+    test "doesn't drop survivor equipment if they aren't carrying too much" do
+      s =
+        Survivor.new()
+        |> add_equipment("Corncob")
+
+      assert 1 == length(s.equipment)
+
+      s =
+        s
+        |> wound
+
+      assert 1 == length(s.equipment)
+    end
+  end
 end