This document discusses the Page Object Model (POM) and Logical Functional Model (LFM) design patterns for automated user testing. POM creates classes to represent pages and abstracts away the testing framework. LFM sits above POM and further abstracts interacting with pages, increasing test code reuse and enabling less technical users to create tests. Both aim to improve test maintainability and reduce brittleness when elements change. The document provides examples of implementing POM and LFM with Selenium.

1. Design Patterns - POM and LFM
Leeds Sharp 27/08/2015 by John Staveley
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Page Object Model and Logical Functional Model
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For automated user testing
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Selenium, WatiN, CodedUI etc
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Increase maintainability and reduce brittleness of UI tests
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NB: I assume you've used a UI testing framework
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(we'll be using Selenium) from www.seleniumhq.org – a
firefox addin

2. A sample page to test

3. Our test: The meaning of life, the universe and
everything....
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CF: Hitchhikers guide to the galaxy, computer at the end of
the universe

4. The meaning of life
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6x7=42

5. Export the test case

6. Some maintenance issues
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6+1-2=5
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66/11=6
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6*4=24
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56-39=18
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Any change to the number 6 breaks all of these tests

7. Page Object Model
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Create a class to represent the page
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Abstract away the operation of the web testing framework

8. Page Object Model in a test

9. Logical Functional Model (LFM)
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Sits as a layer above POM
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Abstracts away further the implementation of interacting with
a page
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Increases reuse of your test code, particularly repeated
operations
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Enables less technical users to create tests

10. LFM – Basic Example

11. LFM – Bad example

12. LFM = BDD

14. LFM