sass-lint/lib/rules/extends-before-declarations.js

Sass linter. Compatible but different from scss-lint

'use strict';

var helpers = require('../helpers');

module.exports = {
  'name': 'extends-before-declarations',
  'defaults': {},
  'detect': function (ast, parser) {
    var result = [],
        error;

    ast.traverseByType('block', function (block) {
      var lastDeclaration = null;
      block.traverse(function (item, j) {
        if (item.type === 'extend') {
          if (j > lastDeclaration && lastDeclaration !== null) {
            item.forEach('simpleSelector', function () {
              error = {
                'ruleId': parser.rule.name,
                'line': item.start.line,
                'column': item.start.column,
                'message': 'Extends should come before declarations',
                'severity': parser.severity
              };
              result = helpers.addUnique(result, error);
            });
          }
        }
        if (item.type === 'declaration') {
          lastDeclaration = j;
        }
      });
      lastDeclaration = null;
    });

    return result;
  }
};