Case Study: User Login Tests in Selenium WebDriver

A super simple automated test case that some might still get wrong.

AgileTravel login page

Test Design

For login tests, there are usually at least two test cases.

  1. One happy case: Login successfully
  2. One alternative case: Login failed from bad credentials

Test Case 1: Login OK

The test script (Selenium + RSpec) below is quite straight-forward, it consists of four steps; just like how it is done manually.

it "[1] Can sign in OK" do
driver.find_element(:id, "username").send_keys("agileway")
driver.find_element(:id, "password").send_keys("testwise")
driver.find_element(:id, "username").submit
expect(driver.page_source).to include("Signed in")

Test Case 2: Login Failed

The steps are the same, except with different input (wrong password) and assertions.

expect(driver.page_source).to include("Invalid email or password")

Refine the Whole Test Script

However, the job is not done yet. While both tests passed individually, we want to make sure the whole test script (including these two together) passes as well. To do that in TestWise (a testing IDE), click the “Run Test Script” button (big blue triangle) on the toolbar.

TestWise’s “Run all tests in the file” button

Analyse and Fix it

After the execution of the first test case, the user is logged in successfully in the browser. The second test tried to continue from there, but it was expecting the login page. That’s why it failed on the first line (line 29) of the second test case.

Click “Sign off” to logout after the login OK case



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