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Comprehensive and Detailed Explanation From Exact Extract JavaScript Knowledge

Definitions:

False negative The test reports a failure even though the feature actually works.

False positive The test reports success when it should not.

True positive Correctly identifies something is working.

True negative Correctly identifies something is not working.

In this scenario:

The checkout button does exist, so the feature works.

The test fails incorrectly, because it is checking for the wrong selector.

That is the definition of a false negative.

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JavaScript Knowledge Reference (text-only)

Test outcome classification: false negative = feature works but test fails.

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