Скачать или смотреть Solving the Pytest Challenge: Ensuring One Test Passes While Another Fails

Discover how to effectively use `pytest` to perform tests in Python, with a focus on making expectations clear and results reliable.
---
This video is based on the question https://stackoverflow.com/q/72841312/ asked by the user 'Jiana' ( https://stackoverflow.com/u/15748395/ ) and on the answer https://stackoverflow.com/a/72842137/ provided by the user 'dosas' ( https://stackoverflow.com/u/3036567/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Pytest - 2 pytest tests, one should pass one should fail

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Solving the Pytest Challenge: Ensuring One Test Passes While Another Fails

When working with automated testing in Python, specifically using the pytest framework, you might encounter scenarios where you need to ensure that one test case passes while another one should intentionally fail. In this guide, we'll explore a common situation where a test is expected to succeed if a certain string is present, and another test should fail when a different string is not found. Let’s break down the solution step by step.

The Scenario

You are tasked with creating two tests in pytest:

Test 1: The test should pass if the string "Right-click in the box below to see one called 'the-internet'" is found on the webpage.

Test 2: Conversely, this test should fail if the string "Alibaba" is not found on the same page.

Here is the initial code you might have written:

[[See Video to Reveal this Text or Code Snippet]]

However, when running this code, both tests pass, which does not meet your expectations.

Understanding the Problem

The core issue lies in the unnecessary use of if statements before assert statements. Using an if statement before an assert is not needed, as the purpose of assert is to directly test the condition you want — if it evaluates to False, pytest will automatically fail the test.

The Solution

To correct the issue, you should revise the tests by removing the if statements. Here’s an improved version of the tests:

[[See Video to Reveal this Text or Code Snippet]]

Step-by-Step Breakdown

Removal of Unnecessary Logic:

Each test should simply perform the assertion without wrapping it in an if statement.

Direct Assertion:

The assert statement checks whether the specified text is in the driver.page_source. If it is not, the test will fail as expected.

Enhancing Your Tests with Parametrization

Further optimization can be achieved using pytest's parameterization feature. This allows you to define a single test function that can handle multiple cases. Here’s how to implement it:

[[See Video to Reveal this Text or Code Snippet]]

Benefits of Parametrization

Code Reduction: Instead of writing separate functions for each test case, you can handle multiple cases in a single function.

Clarity: Each piece of text you are testing is clearly defined in one place, making it easier to maintain and understand.

Conclusion

By streamlining your test cases and eliminating unnecessary conditional logic, you can ensure that your pytest tests behave as expected. The use of parameterization with pytest not only optimizes your testing code but also makes it more readable and maintainable. Go ahead and implement these tips in your projects to see improved results!

Now you're set to pass one test while failing the other!