Add presence and uniqueness validations for problem

app/models/problem.rb

@@ -1,2 +1,4 @@
 class Problem < ActiveRecord::Base
+  validates :title, :content, presence: true
+  validates :title, uniqueness: true
 end

test/controllers/problems_controller_test.rb

@@ -3,6 +3,10 @@ require 'test_helper'
 class ProblemsControllerTest < ActionController::TestCase
   setup do
     @problem = problems(:one)
+    @update = {
+        title: 'New title',
+        content: 'This is the new content'
+    }
   end
 
   test "should get index" do
@@ -18,7 +22,7 @@ class ProblemsControllerTest < ActionController::TestCase
 
   test "should create problem" do
     assert_difference('Problem.count') do
-      post :create, problem: { content: @problem.content, title: @problem.title }
+      post :create, problem: @update
     end
 
     assert_redirected_to problem_path(assigns(:problem))
@@ -35,7 +39,7 @@ class ProblemsControllerTest < ActionController::TestCase
   end
 
   test "should update problem" do
-    patch :update, id: @problem, problem: { content: @problem.content, title: @problem.title }
+    patch :update, id: @problem, problem: @update
     assert_redirected_to problem_path(assigns(:problem))
   end
 

test/fixtures/problems.yml

@@ -1,9 +1,9 @@
 # Read about fixtures at http://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html
 
 one:
-  title: MyString
-  content: MyText
+  title: First title
+  content: The content of the problem
 
 two:
-  title: MyString
-  content: MyText
+  title: Second title
+  content: The content of the second problem

test/models/problem_test.rb

@@ -1,7 +1,29 @@
 require 'test_helper'
 
 class ProblemTest < ActiveSupport::TestCase
-  # test "the truth" do
-  #   assert true
-  # end
+  test "should not save problem without title" do
+    problem = Problem.new(content: 'This is some content')
+    assert_not problem.save
+  end
+
+  test "should not save problem without content" do
+    problem = Problem.new(title: 'Problem title')
+    assert_not problem.save
+  end
+
+  test "should not save problem with duplicate title" do
+    problem = Problem.new(
+        title: problems(:one).title,
+        content: 'This is some content'
+    )
+    assert_not problem.save
+  end
+
+  test "should save correct problem" do
+    problem = Problem.new(
+        title: 'A unique title',
+        content: 'Some content'
+    )
+    assert problem.save
+  end
 end