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

Lodash specific linting rules for ESLint

/**
 * @fileoverview Rule to check if a call to _.forEach should be a call to _.filter
 */
'use strict';

/**
 * @fileoverview Rule to check if a call to _.forEach should be a call to _.filter
 */
//------------------------------------------------------------------------------
// Rule Definition
//------------------------------------------------------------------------------

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

        var getLodashMethodVisitors = _require.getLodashMethodVisitors;

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

        var getFirstFunctionLine = _require2.getFirstFunctionLine;
        var hasOnlyOneStatement = _require2.hasOnlyOneStatement;
        var getMethodName = _require2.getMethodName;
        var isFunctionDefinitionWithBlock = _require2.isFunctionDefinitionWithBlock;
        var collectParameterValues = _require2.collectParameterValues;

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

        var isAliasOfMethod = _require3.isAliasOfMethod;

        var get = require('lodash/get');
        var includes = require('lodash/includes');

        function onlyHasPush(func) {
            var firstLine = getFirstFunctionLine(func);
            var firstParam = get(func, 'params[0]');
            var exp = func && !isFunctionDefinitionWithBlock(func) ? firstLine : firstLine && firstLine.expression;
            return func && hasOnlyOneStatement(func) && getMethodName(exp) === 'push' && !includes(collectParameterValues(firstParam), get(exp, 'callee.object.name'));
        }

        return getLodashMethodVisitors(context, function (node, iteratee, _ref) {
            var method = _ref.method;
            var version = _ref.version;

            if (isAliasOfMethod(version, 'forEach', method) && onlyHasPush(iteratee)) {
                context.report(node, 'Prefer _.map over a _.forEach with a push to an array inside');
            }
        });
    }
};