Issue #11166: remove getFileContents from EmptyLineSeparator

[mahfouz72]

Issue #11166 :
refactor EmptyLineSeparatorCheck to use AST-based logic not getFileContents()

Diff Regression config: https://gist.githubusercontent.com/mahfouz72/afd57aa6e51ca161b7927acd959e5211/raw/9384f843297bb2e10c074bcb33ddc46902d6bd52/check.xml

WIP. just wants to get an initial review from CIs and maintainers

[mahfouz72]

dealing with comment tokens in the AST was weird to me. why it is under modifiers of the next subtree. is there a reason to build AST like this?

  int x;
    // m
     public int m() {
        return 0;
    }

 |--VARIABLE_DEF -> VARIABLE_DEF [4:4]
        |   |--MODIFIERS -> MODIFIERS [4:4]
        |   |--TYPE -> TYPE [4:4]
        |   |   `--LITERAL_INT -> int [4:4]
        |   |--IDENT -> x [4:8]
        |   `--SEMI -> ; [4:9]
        |--METHOD_DEF -> METHOD_DEF [6:3]
        |   |--MODIFIERS -> MODIFIERS [6:3]
        |   |   |--SINGLE_LINE_COMMENT -> // [5:4]
        |   |   |   `--COMMENT_CONTENT ->  m\r\n [5:6]
        |   |   `--LITERAL_PUBLIC -> public [6:3]

@romani @nrmancuso @rnveach
do we have any check that is aware of comments using AST-based logic not file content to take it as a reference?

[mahfouz72]

I will work more on this method. I believe that there are more cases that need to be handled to get the first comment token

[mahfouz72]

Github, generate report

[github-actions]

https://checkstyle-diff-reports.s3.us-east-2.amazonaws.com/3a9b4f9_2024191033/reports/diff/index.html