Add presence and uniqueness validations for 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