Handle nil values in transformations (#7)

lib/transforms/to_integer.ex

@@ -14,7 +14,9 @@ defmodule AbsintheHelpers.Transforms.ToInteger do
 
   @behaviour AbsintheHelpers.Transform
 
-  def call(%{data: data} = item, _opts) when is_binary(data) do
+  def call(item = %{data: nil}, _opts), do: {:ok, item}
+
+  def call(item = %{data: data}, _opts) when is_binary(data) do
     case Integer.parse(data) do
       {int, ""} -> {:ok, %{item | data: int}}
       _ -> {:error, :invalid_integer, %{}}

lib/transforms/trim.ex

@@ -16,7 +16,9 @@ defmodule AbsintheHelpers.Transforms.Trim do
 
   @behaviour AbsintheHelpers.Transform
 
-  def call(%{data: data} = item, _opts) when is_binary(data) do
+  def call(item = %{data: nil}, _opts), do: {:ok, item}
+
+  def call(item = %{data: data}, _opts) when is_binary(data) do
     {:ok, %{item | data: String.trim(data)}}
   end
 

mix.exs

@@ -4,7 +4,7 @@ defmodule AbsintheHelpers.MixProject do
   def project do
     [
       app: :absinthe_helpers,
-      version: "0.1.6",
+      version: "0.1.7",
       elixir: "~> 1.16",
       start_permanent: Mix.env() == :prod,
       deps: deps(),

test/absinthe_helpers/transforms/to_integer_test.exs

@@ -3,6 +3,12 @@ defmodule AbsintheHelpers.Transforms.ToIntegerTest do
 
   alias AbsintheHelpers.Transforms.ToInteger
 
+  test "to_integer transformation on nil value" do
+    input = %{data: nil}
+
+    assert {:ok, %{data: nil}} = ToInteger.call(input, [])
+  end
+
   test "to_integer transformation on valid string" do
     input = %{data: "123"}
 

test/absinthe_helpers/transforms/trim_test.exs

@@ -3,6 +3,12 @@ defmodule AbsintheHelpers.Transforms.TrimTest do
 
   alias AbsintheHelpers.Transforms.Trim
 
+  test "trim transformation on nil value" do
+    input = %{data: nil}
+
+    assert {:ok, %{data: nil}} = Trim.call(input, [])
+  end
+
   test "trim transformation on string" do
     input = %{data: "  hello  "}