/**
   * @fileoverview Rule to flag comparisons to null without a type-checking
   * operator.
   * @author Ian Christian Myers
   */
  
  "use strict";
  
  //------------------------------------------------------------------------------
  // Rule Definition
  //------------------------------------------------------------------------------
  
  module.exports = {
      meta: {
          docs: {
              description: "disallow `null` comparisons without type-checking operators",
              category: "Best Practices",
              recommended: false
          },
  
          schema: []
      },
  
      create(context) {
  
          return {
  
              BinaryExpression(node) {
                  const badOperator = node.operator === "==" || node.operator === "!=";
  
                  if (node.right.type === "Literal" && node.right.raw === "null" && badOperator ||
                          node.left.type === "Literal" && node.left.raw === "null" && badOperator) {
                      context.report({ node, message: "Use ‘===’ to compare with ‘null’." });
                  }
              }
          };
  
      }
  };