/**
   * @fileoverview Rule to disallow a duplicate case label.
   * @author Dieter Oberkofler
   * @author Burak Yigit Kaya
   */
  
  "use strict";
  
  //------------------------------------------------------------------------------
  // Rule Definition
  //------------------------------------------------------------------------------
  
  module.exports = {
      meta: {
          docs: {
              description: "disallow duplicate case labels",
              category: "Possible Errors",
              recommended: true
          },
  
          schema: []
      },
  
      create(context) {
          const sourceCode = context.getSourceCode();
  
          return {
              SwitchStatement(node) {
                  const mapping = {};
  
                  node.cases.forEach(switchCase => {
                      const key = sourceCode.getText(switchCase.test);
  
                      if (mapping[key]) {
                          context.report({ node: switchCase, message: "Duplicate case label." });
                      } else {
                          mapping[key] = switchCase;
                      }
                  });
              }
          };
      }
  };