Maximum call stack size exceeded

[daniel-jonathan]

Hi,

I keep getting this error when I call this.render using koa-jade:

---

server error [RangeError: Maximum call stack size exceeded] { request:
{ method: 'GET',
url: '/daniel',
header:
{ 'x-real-ip': '10.211.55.2',
'x-forwarded-for': '10.211.55.2',
host: 'docs.sandbox.local:80',
'x-nginx-proxy': 'true',
connection: 'close',
'cache-control': 'max-age=0',
accept: 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,/;q=0.8',
'upgrade-insecure-requests': '1',
'user-agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2490.80 Safari/537.36',
'accept-encoding': 'gzip, deflate, sdch',
'accept-language': 'en-US,en;q=0.8',
cookie: '_ga=GA1.2.1728672733.1439768627' } },
response:
{ status: 200,
message: 'OK',
header:
{ 'access-control-allow-origin': '*',
'access-control-allow-methods': 'GET,HEAD,PUT,POST,DELETE',
'cache-control': 'no-cache',
'content-type': 'text/html; charset=utf-8',
'content-length': '19' } },
app: { subdomainOffset: 2, env: 'development' },
originalUrl: '/daniel',
req: '',
res: '',
socket: '' }

---

This is the code:

'use strict';
'use esnext';

function *base(route, next) {
yield this.render('base', {
title: 'Docs',
styles: [
// materialize
'/materialize.min.css',

        // material icons
        '/css/materialdesignicons.min.css',

        // graphkit
        '/app.css'
    ],
    vendors: [
        // jquery
        '/jquery.min.js',

        // angular
        '/angular.min.js',
        '/angular-aria.min.js',
        '/angular-route.min.js',

        // materialize
        '/materialize.min.js',

        // d3
        '/d3.min.js'
    ],
    packages: [
        // app
        '/app.js',
        '/auth.js',
        '/connect.js',
        '/http.js',
        '/router.js'
    ]
}, true);

if (undefined !== next) {
    yield next;
}

}

function *index(route, next) {
yield this.render('routes/index', {}, true);
}

function *profile(route, next) {
yield this.render('routes/profile', {}, true);
}

function *error(route, next) {
yield this.render('routes/error404', {}, true);
}

module.exports = function(app) {
const koaRoute = require('koa-route');
const koaJade = require('koa-jade');
const jade = new koaJade({
viewPath: __dirname + '/src/views',
debug: 'development' == app.env,
pretty: 'development' == app.env,
compileDebug: 'development' == app.env,
locals: {
title: 'Docs'
},
basedir: '/',
noCache: true,
helperPath: [
//'path/to/jade/helpers',
//{ random: 'path/to/lib.js' },
]
});

app.use(jade.middleware);

// base
app.use(koaRoute.get('/', base));
app.use(koaRoute.get('/a/welcome', base));
app.use(koaRoute.get('/:username', base));

// index
app.use(koaRoute.get('/route/index', index));

// profile
app.use(koaRoute.get('/route/profile', profile));

};

[qw3r]

@DanielDahan Can you, please explain how did you managed to solve this issue?

[albertogasparin]

I've solved it by removing yeld:

router.get('/', function *() {
  this.render('index', { a: b });
});

However it might not be the behaviour you want.

[watzon]

Can we reopen this until there is a fix that doesn't require removing yield statements? They're kind of important

[daniel-jonathan]

I looked over my code, and I also removed the yield call.

[chrisyip]

this.render doesn't require yield statement, it just a normal function.

Here's the reasons:

Normal function is faster than generator function:

iojs 1.6.4
Normal function x 163,231 ops/sec ±1.33% (180 runs sampled)
Generator function x 74,904 ops/sec ±1.86% (173 runs sampled)

Koa team encourages to use normal functions (see v2):

app.use(ctx => {
  ctx.body = 'Hello World';
})

I'll update the doc.

[ladytellur]

@chrisyip some of us just wants to use koa@1 until async/await will become native in stable Node version

[chrisyip]

@ladytellur koa-pug supports koa@1 and koa@2, just use this.render() without yield:

const app = new Koa
const pug = new Pug({ /* options */ })
pug.use(app)

app.use(function* () {
  this.render('index')
})