Vue Unit Testing #26 - Activity item component test

Summary

This video discusses the testing scenario for a base select component, focusing on how the reset button interacts with an activity object’s `secondsToComplete` property. When the select box is reset, the `select` event payload contains a null value, which triggers the reset of the `secondsToComplete` property to zero. The script walks through the test case where the reset button fires the select handler with a null value, ensuring the property is updated correctly. The video concludes by confirming the success of the test and ensuring all tests pass in the project.

Takeaways

• 😀 The test scenario focuses on ensuring that when the reset button is clicked on the select box, the 'seconds to complete' property of an activity object is updated to zero.
• 😀 The `select` event payload will contain a `null` value after the reset, which triggers the necessary logic to reset the 'seconds to complete' field.
• 😀 The `normalizedSelectVal` function returns the value passed to it, handling the `null` value appropriately, leading to a reset of the 'seconds to complete' field.
• 😀 The test scenario includes verifying that the select box reset updates the corresponding property in the activity object to zero.
• 😀 The test checks that after the select box reset, the payload of the select event is `null`, confirming the select handler behavior.
• 😀 The test case ensures that when the payload is `null`, the 'seconds to complete' value is updated to zero, which matches the expected behavior of the system.
• 😀 The importance of handling edge cases such as `null` values in event payloads is demonstrated by the reset functionality.
• 😀 A failure scenario is included where if the `or` expression is modified incorrectly or removed, the test would fail, highlighting the significance of correct logic.
• 😀 The test verifies the behavior by comparing the updated activity object to ensure the correct value (zero) is assigned to 'seconds to complete'.
• 😀 The final step is ensuring all tests pass in the project, validating that the reset functionality and its integration with other components work as expected.

Q & A

What is the purpose of the reset button in the described scenario?

The reset button is used to reset the select box value, which, in turn, updates the `secondsToComplete` property of an activity object to zero.

What does the `selectHandler` function do after the reset button is clicked?

After the reset button is clicked, the `selectHandler` function is triggered with a payload containing a null value, which updates the `secondsToComplete` property of the activity object.

Why is the `null` payload significant in the select event?

The `null` payload signifies that the select box was reset, which causes the `secondsToComplete` property to be set to zero in the activity object.

What is the role of the `normalizedSelectVal` function in this process?

The `normalizedSelectVal` function checks if the payload value is null, and if it is, it returns the null value, causing the `secondsToComplete` property of the activity object to be updated to zero.

How does the reset action affect the `secondsToComplete` property of the activity object?

The reset action sets the `secondsToComplete` property of the activity object to zero, as a result of the select box being reset and the null value being passed through the `selectHandler` function.

What happens if the `or` expression is modified in the code?

If the `or` expression is modified, the test will throw an error, as the logic will no longer correctly handle the `null` payload, leading to incorrect behavior and failing the test.

What test is being set up in the provided script?

The test is designed to check that when the select box is reset, the `secondsToComplete` property of the activity object is updated to zero, and the select event's payload is null.

How does the test handle the reset scenario for the select box?

The test simulates clicking the reset button, which triggers the `selectHandler` function. It checks if the activity object's `secondsToComplete` property is updated to zero and if the payload of the select event is null.

What would cause the test to fail according to the transcript?

The test would fail if the `or` expression is modified incorrectly, or if null is not assigned correctly to the `secondsToComplete` property, as it would lead to unexpected results.

What is the expected outcome of the test after resetting the select box?

The expected outcome is that the `secondsToComplete` property of the activity object is updated to zero, and the select event’s payload is null, confirming the reset behavior works as intended.