Java: port quality query java/mocking-all-non-private-methods-means-unit-test-is-too-big

[Napalys]

Ported the java/mocking-all-non-private-methods-means-unit-test-is-too-big query. Key changes:

• Classes with only 1 public method being mocked are no longer flagged as true positives.
• MRVA 1000 reduced from 1,332 to 250 results.
• Autofix: Primarily focuses on trimming test cases to test a single method, which may or may not be considered as a acceptable fix as it may now not cover trimmed methods.

[Copilot]

Pull Request Overview

Ports the java/mocking-all-non-private-methods-means-unit-test-is-too-big query to detect unit tests that mock all public methods of a class, which may indicate the test is testing too much functionality.

Key changes:

• Added logic to exclude classes with only 1 public method from being flagged as violations
• Reduced false positive results from 1,332 to 250 on MRVA 1000
• Added comprehensive test stubs for Mockito 5.14 and JUnit 4.13 to support the query functionality

Reviewed Changes

Copilot reviewed 30 out of 30 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
java/ql/src/Likely Bugs/Frameworks/JUnit/MockingAllNonPrivateMethodsMeansUnitTestIsTooBig.ql	Main query implementation that detects excessive mocking patterns
java/ql/src/Likely Bugs/Frameworks/JUnit/MockingAllNonPrivateMethodsMeansUnitTestIsTooBig.md	Documentation explaining the rule and providing usage examples
java/ql/test/query-tests/MockingAllNonPrivateMethodsMeansUnitTestIsTooBig/	Test cases with expected results demonstrating compliant and non-compliant patterns
java/ql/test/stubs/mockito-5.14/	Mockito framework stubs for testing support
java/ql/test/stubs/junit-4.13/	JUnit 4.13 framework stubs for testing support
java/ql/integration-tests/java/query-suite/*.qls.expected	Updated query suite expectations to include the new rule

[michaelnebel]

Overall this looks good! Only a few questions / comments.

[michaelnebel]

LGTM!

[owen-mc]

I don't think "Likely Bugs" is the best folder for this query.

My only other concern is with the autofixes. Do you think they are good enough to add this to show the autofixes to users? Can you think of any way of improving them, e.g. with more complete examples in the qhelp?

[Napalys]

@owen-mc

I don't think "Likely Bugs" is the best folder for this query.

Fair point, I agree. The main reason I moved it there was because of the Frameworks/JUnit. Do you have any suggestions for where it would fit better? Thank you ❤️

My only other concern is with the autofixes. Do you think they are good enough to add this to show the autofixes to users? Can you think of any way of improving them, e.g. with more complete examples in the qhelp?

I will try to think of something. 🤔

[owen-mc]

I think `Violations of Best Practice" is the best high-level folder. None of the existing subfolders really match, so maybe create a new one called "Testing".

It is an option to accept that autofixes aren't good for this query at the moment, and not add it to autofix.