solium-plugin-security/rules/else-after-elseif.js

Official Solium Plugin for Security-related lint rules

/**
 * @fileoverview Encourage else blocks after else-if blocks
 * @author Michelle Pokrass <michellepokrass@gmail.com>
 */

"use strict";

module.exports = {

    meta: {
        docs: {
            description: "Encourage else blocks after else-if blocks",
            recommended: false,
            type: "off"
        },

        schema: []
    },

    create(context) {
        function inspectElseIfStatement(node) {
            // if the else if does not have an alternate, that means there is
            // no else - report an error
            if (!node["alternate"]) {
                context.report({
                    node: node,
                    message: "\"else if\" statement must be followed by an \"else\" statement"
                });
            } else if (node["alternate"]["type"] === "IfStatement") {
                inspectElseIfStatement(node["alternate"]); 
            }
        }

        function inspectIfStatement(emitted) {
            if (emitted.exit) { return; }
            let node = emitted.node;

            let sourceCode = context.getSourceCode();
            let parent = sourceCode.getParent(node);

            // only inspect top-level if statements
            if (parent["type"] == "IfStatement") {
                return;
            }

            if (node["alternate"] && node["alternate"]["type"] === "IfStatement") {
                inspectElseIfStatement(node["alternate"]);
            }
        }

        return {
            IfStatement: inspectIfStatement 
        };
    }

};