diff --git a/test/httparrot_test.exs b/test/httparrot_test.exs
new file mode 100644
index 0000000..f393498
--- /dev/null
+++ b/test/httparrot_test.exs
@@ -0,0 +1,25 @@
+defmodule HTTParrotTest do
+  use ExUnit.Case
+  import :meck
+  import HTTParrot
+
+  setup do
+    new :cowboy_req
+  end
+
+  teardown do
+    unload :cowboy_req
+  end
+
+  test "'prettify_json' prettifies body response if it's a JSON" do
+    expect(:cowboy_req, :reply, [{[:status, [{"content-length", '14'}], "{\n  \"a\": \"b\"\n}", :req1], {:ok, :req2}}])
+    assert prettify_json(:status, [{"content-length", '12'}], "{\"a\":\"b\"}", :req1) == :req2
+    assert validate :cowboy_req
+  end
+
+  test "'prettify_json' does nothing if body is not a JSON" do
+    expect(:cowboy_req, :reply, [{[:status, :headers, "<xml></xml>", :req1], {:ok, :req2}}])
+    assert prettify_json(:status, :headers, "<xml></xml>", :req1) == :req2
+    assert validate :cowboy_req
+  end
+end