eslint-plugin-lodash/lib/rules/prefer-chain.js

Lodash specific linting rules for ESLint

/**
 * @fileoverview Rule to check if the expression could be better expressed as a chain
 */
'use strict';

/**
 * @fileoverview Rule to check if the expression could be better expressed as a chain
 */
//------------------------------------------------------------------------------
// Rule Definition
//------------------------------------------------------------------------------

module.exports = {
    meta: {
        schema: [{
            type: 'integer',
            minimum: 2
        }]
    },

    create: function create(context) {
        var _require = require('../util/lodashUtil');

        var isLodashCall = _require.isLodashCall;
        var getLodashImportVisitors = _require.getLodashImportVisitors;

        var _require2 = require('../util/astUtil');

        var getCaller = _require2.getCaller;

        var _require3 = require('../util/ruleUtil');

        var combineVisitorObjects = _require3.combineVisitorObjects;

        var DEFAULT_LENGTH = 3;
        var settings = require('../util/settingsUtil').getSettings(context);
        var ruleDepth = parseInt(context.options[0], 10) || DEFAULT_LENGTH;

        function isNestedNLevels(node, n) {
            return n === 0 || isLodashCall(node, settings.pragma, context) && isNestedNLevels(node.arguments[0], n - 1);
        }

        return combineVisitorObjects({
            CallExpression: function CallExpression(node) {
                if (isNestedNLevels(node, ruleDepth)) {
                    context.report(getCaller(node.arguments[0]), 'Prefer chaining to composition');
                }
            }
        }, getLodashImportVisitors(context));
    }
};