Issue #11720: Kill surviving mutation in RequireThisCheck related to static blocks

[Vyom-Yadav]

#11720
Hardcoded mutation tested at #11776

Reports with hardcoded mutation (clean):

• DefaultConfig: https://checkstyle-diff-reports.s3.us-east-2.amazonaws.com/dc3d699_2022053018/reports/diff/index.html
• validateOnlyOverlappingFalseWithoutOpenJDK: https://checkstyle-diff-reports.s3.us-east-2.amazonaws.com/dc3d699_2022072839/reports/diff/index.html

validateOnlyOverlapping = false report was not generated with OpenJDK (Out of memory in GitHub actions), though it is very unlikely that it will show any difference, still, if it is required, ping me, and I will generate it locally.

This mutation falls in the category:

• Safely (no regressions) remove code to be covered

Rationale:

The condition definitionToken.getType() == TokenTypes.STATIC_INIT is same as the condition
codeBlockDefinition.getType() == TokenTypes.STATIC_INIT. A variable declared in static block scope, will always have an enclosing CLASS_FRAME.

In the current logic, we skip all frames of type BLOCK_FRAME, and FOR_FRAME to reach the CLASS_FRAME, if we can't reach CLASS_FRAME (maybe METHOD_FRAME is in between), then we can be assured that there is no static block present.

So if there is a static block, we will surely go into the branch
if (variableDeclarationFrame.getType() == FrameType.CLASS_FRAME) in which we check for the condition-

staticContext = codeBlockDefinition.getType() == TokenTypes.STATIC_INIT
    || modifiers.findFirstToken(TokenTypes.LITERAL_STATIC) != null;

Hence the line can be safely removed, in theory, we would take a hit in TC, as we would make another traversal in getCodeBlockDefinitionToken(..) but in reality, there will be no difference, in real case use scenario, 2-3 more iterations.

---

Generating reports again:

Diff Regression config: https://gist.githubusercontent.com/Vyom-Yadav/98dceb63a79f4833e85fff9b2e1464a6/raw/5dc88b466a50335d5759f60c1d041a239f11a5a1/my_checks.xml
Diff Regression projects: https://gist.githubusercontent.com/Vyom-Yadav/91807e6244cff60698d9e33e32ba2d51/raw/ccf3b6b9e053f27b371eb6d1e848d7199dd1f567/projects-to-test-on.properties
Report label: validateOnlyOverlappingFalseWithoutOpenJDK

[nrmancuso]

Please generate check regression reports for this PR.

[Vyom-Yadav]

Github, generate report

[github-actions]

DefaultConfig: https://checkstyle-diff-reports.s3.us-east-2.amazonaws.com/dc3d699_2022053018/reports/diff/index.html

[Vyom-Yadav]

Github, generate report

[github-actions]

validateOnlyOverlappingFalseWithoutOpenJDK: https://checkstyle-diff-reports.s3.us-east-2.amazonaws.com/dc3d699_2022072839/reports/diff/index.html