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.
• DCA https://github.com/github/codeql-dca-main/issues/30679
• 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

[Copilot]

[nitpick] Consider extracting this count condition into a predicate for better readability and reusability. For example, create a predicate hasMultiplePublicMethods(ClassOrInterface c) that encapsulates this logic.

Suggested change

	count(Method m | m = mockedClassOrInterface.getAMethod() and m.isPublic()) > 1 and
	hasMultiplePublicMethods(mockedClassOrInterface) and