Late to the party - I think this is the second time I've ended up on this SO post so I'll share my js-based solution (I ended up making a bookmarklet by just fetching and searching the html pages).
You can either create a bookmarklet from this, or simply paste the whole thing into the console. Works on chromium-based and firefox:
EDIT: if there are more than 10 or so forks on the page, you may get locked out for scraping too fast (429 too many requests in network). Use async / await instead:
javascript:(async () => {
/* while on the forks page, collect all the hrefs and pop off the first one (original repo) */
const forks = [...document.querySelectorAll('div.repo a:last-of-type')].map(x => x.href).slice(1);
for (const fork of forks) {
/* fetch the forked repo as html, search for the "This branch is [n commits ahead,] [m commits behind]", print it to console */
await fetch(fork)
.then(x => x.text())
.then(html => console.log(`${fork}: ${html.match(/This branch is.*/).pop().replace('This branch is ', '')}`))
.catch(console.error);
}
})();
or you can do batches, but it's pretty easy to get locked out
javascript:(async () => {
/* while on the forks page, collect all the hrefs and pop off the first one (original repo) */
const forks = [...document.querySelectorAll('div.repo a:last-of-type')].map(x => x.href).slice(1);
getfork = (fork) => {
return fetch(fork)
.then(x => x.text())
.then(html => console.log(`${fork}: ${html.match(/This branch is.*/).pop().replace('This branch is ', '')}`))
.catch(console.error);
}
while (forks.length) {
await Promise.all(forks.splice(0, 2).map(getfork));
}
})();
Original (this fires all requests at once and will possibly lock you out if it is more requests/s than github allows)
javascript:(() => {
/* while on the forks page, collect all the hrefs and pop off the first one (original repo) */
const forks = [...document.querySelectorAll('div.repo a:last-of-type')].map(x => x.href).slice(1);
for (const fork of forks) {
/* fetch the forked repo as html, search for the "This branch is [n commits ahead,] [m commits behind]", print it to console */
fetch(fork)
.then(x => x.text())
.then(html => console.log(`${fork}: ${html.match(/This branch is.*/).pop().replace('This branch is ', '')}`))
.catch(console.error);
}
})();
Will print something like:
https://github.com/user1/repo: 289 commits behind original:master.
https://github.com/user2/repo: 489 commits behind original:master.
https://github.com/user2/repo: 1 commit ahead, 501 commits behind original:master.
...
to console.
EDIT: replaced comments with block comments for paste-ability
