diff --git a/test/integration/login_test.rb b/test/integration/login_test.rb
--- a/test/integration/login_test.rb
+++ b/test/integration/login_test.rb
@@ -5,9 +5,33 @@
   #   assert true
   # end
 
-  test "login with valid information" do
+  test "login with invalid information" do
+    get root_path
+    assert_response :success
+    post login_login_path, login: "root", password: "hahaha"
+    assert_redirected_to root_path
+  end
+
+  test "normal user login" do
     get root_path
     assert_response :success
+    post login_login_path, {login: "john", password: "hello" }
+    assert_redirected_to main_list_path
+  end
 
+  test "normal user login in single_user mode" do
+    GraderConfiguration[GraderConfiguration::SINGLE_USER_KEY] = 'true'
+    get root_path
+    assert_response :success
+    post login_login_path, {login: "john", password: "hello" }
+    assert_redirected_to root_path
+  end
+
+  test "root login in in single_user mode" do
+    GraderConfiguration[GraderConfiguration::SINGLE_USER_KEY] = 'true'
+    get root_path
+    assert_response :success
+    post login_login_path, {login: "admin", password: "admin" }
+    assert_redirected_to main_list_path
   end
 end