Case Study: Locator Chaining in Selenium WebDriver

Cleaner and more readable locators in Selenium tests with Locator Chaining

A repost of my daughter’s article with permission. I added a few notes. This is also included in my “How to in Selenium WebDriver” series.

Locator Chaining, in test automation, is a way to find an element relative to another. I will illustrate how to use locator chaining with a real example in this article.

Table of Contents:
· One Selenium Test Failed
· Analyse
· The Problem — Multiple Elements
· The Solution — Locator Chaining
∘ 1. Find all matching elements
∘ 2. Filter for displayed elements
∘ 3. Get the first displayable notification badge
∘ 4. Use Locator Chaining to go back to the parent elements
· Zhimin’s notes

One Selenium Test Failed

This test (for my fathers’ WhenWise app) is to verify if a group training is available on Saturday, marked with the number in a red circle.

The test passed yesterday. After a code change, the test started to fail with the below comparison error.

Failure/Error: try_for(2) { expect(select_training_class_page.first_available_date_label_regardless_displayed).to include("SAT") }
RuntimeError:
Timeout after 2 seconds with error: expected "FRI\n30/12" to include "SAT"

Diff:
@@ -1,2 +1,3 @@
-SAT
+FRI
+30/12

It seemed to select the “FRI” tab instead of “SAT”. What went wrong here?

Analyse

It could be a bad code change. However, there was actually no visible change on the week selection page.