Allow sync usage

[ArmorDarks]

It would be great if async usage would be optional

So far forceful usage of async in SVGO causes a lot of pain in libraries, which can't handle natively async calls. For example, some templates language doesn't play well with it at all.

Any chances for optional sync implementation?

[ArmorDarks]

I see some efforts have been made here #580, though, they didn't succeed.

[GreLI]

I'm afraid the only option use it sync is to wait for execution in command prompt.

[ArmorDarks]

<irony>10 out of 10 solution</irony>

[yvele]

@ArmorDarks It's maybe a bit ugly but you can make a hack using deasync

import SVGO from "svgo";
import deasync from "deasync";

function svgoOptimizeSync(svgo, content) {
  let res;
  svgo.optimize(content, result => res = result);
  deasync.loopWhile(() => !res);
  return res;
}

PS: I've made a gist of it

[ArmorDarks]

@yvele Thanks for additional solution. Unfortunately, it implies additional dependency or a hack, which we'd like to avoid.

I think the real issue here is that SVGO does not use promises and instead relies on callback. Otherwise it would be very easy to do with async function. But as right of now, we're forced to use deascyn-like hacks, or use some means to promisify SVGO, which, I'd say, isn't ok on 2017.

Though, I don't want to insult developers. SVGO is great library and it saved us like a ton of kbs and time.

[GreLI]

SVGO has appeared when there was no promises.

[ArmorDarks]

Yeap, I know.

[GreLI]

SVGO.optimize() now returns Promise in v1.0.0.