start writing tests

app/controllers/users_controller.rb

@@ -1,2 +1,23 @@
 class UsersController < ApplicationController
+  
+  # GET /signup
+  def new
+    @user = User.new
+  end
+
+  # POST /signup
+  def create
+    user = User.new(user_params)
+    if user.save
+      login(user)
+    else
+      render :new
+    end
+  end
+
+  private
+
+  def user_params
+    params.require(:user).permit(:name, :email, :password, :password_confirmation)
+  end
 end