How do you approach testing complex UI components that generate deep nested DOM nodes without convenient identifiers? How do you target specific interface elements in E2E tests?

When testing complex UI components with deeply nested DOM and lacking convenient identifiers, it is important to use stable and understandable selectors:

• Adding data attributes: the most reliable way is to agree with developers to add special attributes, such as data-test-id, which do not affect styles and structure but serve for testing.

• Using text content: if there are unique texts or aria-labels, you can base your selectors on them.

• Combined selectors: combining classes, element types, and their hierarchy, for example, div > ul > li:nth-child(2) > button.

• Using libraries for E2E with selector support: for example, Cypress or Playwright allow writing selectors considering visibility, text, and attributes.

• Circumventing deep nesting: you can write helper functions that search for elements based on certain features rather than strict structure.

Example of a selector with a data attribute in Cypress:

cy.get('[data-test-id="submit-button"]').click();

If data attributes are absent, you can use text:

cy.contains('button', 'Send').click();

Thus, the key is to agree on stable selectors or use text and aria attributes so that tests are resilient to layout changes.