disallow-trailing-comma.js

var Checker = require('../../../lib/checker');
var reportAndFix = require('../../lib/assertHelpers').reportAndFix;
var expect = require('chai').expect;

describe('rules/disallow-trailing-comma', function() {
    var checker;
    var rules = { disallowTrailingComma: true };

    beforeEach(function() {
        checker = new Checker();
        checker.registerDefaultRules();
        checker.configure(rules);
    });

    reportAndFix({
        name: 'comma in object literal',
        rules: rules,
        errors: 1,
        input: '({b: 2,})',
        output: '({b: 2})'
    });

    reportAndFix({
        name: 'comma in object literal with couple properties',
        rules: rules,
        errors: 1,
        input:  '({a: 1, b: 2,})',
        output: '({a: 1, b: 2})'
    });

    it('should report trailing comma in object literal', function() {
        expect(checker.checkString('var x = {a: "a", b: "b"}')).to.have.no.errors();
        expect(checker.checkString('var x = {a: "a", b: "b"\n}')).to.have.no.errors();
        expect(checker.checkString('var x = {a: "a", b: "b",}'))
          .to.have.one.validation.error.from('disallowTrailingComma');
        expect(checker.checkString('var x = {a: "a", b: "b",\n}'))
          .to.have.one.validation.error.from('disallowTrailingComma');
    });

    it('should report trailing comma in array', function() {
        expect(checker.checkString('var x = [1, 2]')).to.have.no.errors();
        expect(checker.checkString('var x = [1, 2\n]')).to.have.no.errors();
        expect(checker.checkString('var x = [1, 2,]')).to.have.one.validation.error.from('disallowTrailingComma');
        expect(checker.checkString('var x = [1, 2,\n]')).to.have.one.validation.error.from('disallowTrailingComma');
    });

    it('should report right location for trailing comma in object (#1018)', function() {
        var errs = checker.checkString('var obj = {\n    foo: "foo",\n};').getErrorList();
        expect(errs[0].line + ':' + errs[0].column).to.equal('2:15');
    });

    it('should report right location for trailing comma in array (#1018)', function() {
        var errs = checker.checkString('var arr = [\n    \'foo\',\n];').getErrorList();
        expect(errs[0].line + ':' + errs[0].column).to.equal('2:10');
    });

});