diff --git a/lib/igniter.ex b/lib/igniter.ex
index fe1c997..da14e87 100644
--- a/lib/igniter.ex
+++ b/lib/igniter.ex
@@ -651,7 +651,7 @@ defmodule Igniter do
               "These dependencies #{IO.ANSI.yellow()}should#{IO.ANSI.reset()} be installed before continuing. Modify mix.exs and install?"
             end
 
-          if opts[:yes] || Mix.shell().yes?(message) do
+          if opts[:yes] || Igniter.Util.IO.yes?(message) do
             rewrite =
               case Rewrite.write(rewrite, "mix.exs", :force) do
                 {:ok, rewrite} -> rewrite
@@ -685,7 +685,7 @@ defmodule Igniter do
               "These dependencies #{IO.ANSI.yellow()}should#{IO.ANSI.reset()} be installed before continuing. Modify mix.exs and install?"
             end
 
-          if Mix.shell().yes?(message) do
+          if Igniter.Util.IO.yes?(message) do
             rewrite =
               case Rewrite.write(igniter.rewrite, "mix.exs", :force) do
                 {:ok, rewrite} -> rewrite
@@ -793,7 +793,7 @@ defmodule Igniter do
           result_of_dry_run
         else
           if opts[:yes] ||
-               Mix.shell().yes?(opts[:confirmation_message] || "Proceed with changes?") do
+               Igniter.Util.IO.yes?(opts[:confirmation_message] || "Proceed with changes?") do
             igniter.rewrite
             |> Enum.any?(fn source ->
               Rewrite.Source.from?(source, :string) || Rewrite.Source.updated?(source)
@@ -901,7 +901,7 @@ defmodule Igniter do
                 Igniter.assign(igniter, :prompt_on_git_changes?, false)
 
               _ ->
-                if Mix.shell().yes?("Uncommitted changes detected in the project. Continue?") do
+                if Igniter.Util.IO.yes?("Uncommitted changes detected in the project. Continue?") do
                   Igniter.assign(igniter, :prompt_on_git_changes?, false)
                 else
                   exit({:shutdown, 1})
diff --git a/lib/igniter/project/deps.ex b/lib/igniter/project/deps.ex
index 4d48273..9dc5279 100644
--- a/lib/igniter/project/deps.ex
+++ b/lib/igniter/project/deps.ex
@@ -50,7 +50,7 @@ defmodule Igniter.Project.Deps do
           igniter
         else
           if opts[:yes?] ||
-               Mix.shell().yes?("""
+               Igniter.Util.IO.yes?("""
                Dependency #{name} is already in mix.exs. Should we replace it?
 
                Desired: `#{inspect(desired)}`
diff --git a/lib/igniter/util/io.ex b/lib/igniter/util/io.ex
new file mode 100644
index 0000000..4b60520
--- /dev/null
+++ b/lib/igniter/util/io.ex
@@ -0,0 +1,18 @@
+defmodule Igniter.Util.IO do
+  @moduledoc "Helpers for working with input/output"
+
+  @doc "Prompts the user for yes or no, repeating the prompt until a satisfactory answer is given"
+  def yes?(prompt) do
+    case String.trim(Mix.shell().prompt(prompt <> " [Yn]")) do
+      yes when yes in ["y", "Y", "yes", "YES"] ->
+        true
+
+      no when no in ["n", "N", "no", "NO"] ->
+        false
+
+      value ->
+        Mix.shell().info("Please enter one of [Yn]. Got: #{value}")
+        yes?(prompt)
+    end
+  end
+end
diff --git a/test/igniter/extensions/phoenix_test.exs b/test/igniter/extensions/phoenix_test.exs
index 8af7ef9..17d2e96 100644
--- a/test/igniter/extensions/phoenix_test.exs
+++ b/test/igniter/extensions/phoenix_test.exs
@@ -45,7 +45,7 @@ defmodule Igniter.Extensions.PhoenixTest do
                Igniter.Extensions.Phoenix.proper_location(igniter, TestWeb.FooHTML, [])
     end
 
-    test "when not belonging to a controller, we instruct to keep its current location" do
+    test "when not belonging to a controller, we say we don't know where it goes" do
       igniter =
         test_project()
         |> Igniter.create_new_file("lib/test_web/controllers/foo_html.ex", """
@@ -54,7 +54,7 @@ defmodule Igniter.Extensions.PhoenixTest do
         end
         """)
 
-      assert :keep =
+      assert :error =
                Igniter.Extensions.Phoenix.proper_location(igniter, TestWeb.FooHTML, [])
     end