Developer guide
Custom rules for each linter are implemented differently based on the tool capabilities and the limitations of the underlying language parser. Below are the details on which classes to extend for each linter.
graph LR
A[<i>Checkstyle</i>] --> B{Is the rule<br>about Javadoc?};
B --> |No| C[Is it achievable<br>using AST?];
C --> |No| D[<b>AbstractFileSetCheck</b>];
C --> |Yes| E[<b>AbstractCheck</b>];
B --> |Yes| F[<b>AbstractJavadocCheck</b>];graph LR
A[<i>CodeNarc</i>] --> B{Is the rule<br>about imports?};
B --> |No| C[Is it achievable<br>using AST?];
C --> |No| D[<b>AbstractRule</b>];
C --> |Yes| E[<b>AbstractAstVisitorRule</b>];
B --> |Yes| F[<b>AbstractImportRule</b>];graph LR
A[<i>Ktlint</i>] --> B[<b>Rule</b> supports AST and raw file];graph LR
A[<i>Pylint</i>] --> B{Is it achievable<br>using AST?};
B --> |No| C[Is it achievable<br>using tokens?];
C --> |No| D[<b>BaseRawFileChecker</b>];
C --> |Yes| E[<b>BaseTokenChecker</b>];
B --> |Yes| F[<b>BaseChecker</b>];Debugging¶
Printing the AST tree to the console is possible with Checkstyle and Ktlint.
Warning
This command is no longer available in newer versions of Ktlint, use version 0.47.0.