pify for gm doesn't seems to be working

Hi,

I’m trying to fix AVA tests for some functionality and I need to Promisify gm(...).size() function. Unfortunately I’m not able to do that properly:

const out = await pify(gm(image.data).size());
console.log("gm output: " + out.width);
---
  gm output: undefined

const out = await pify(gm(image.data).size)();
console.log("gm output: " + out.width);
---
  1 failed

  resize-jpeg › Resize JPEG with jpegoptim
  Error: Cannot read property 'size' of undefined
    proto.(anonymous function) (node_modules/gm/lib/getters.js:47:20)
    node_modules/pify/index.js:29:7
    node_modules/pify/index.js:12:10
    ret (node_modules/pify/index.js:56:34)
    Test.<anonymous> (test/resize-jpeg.js:37:20)
    Generator.next (<anonymous>)

const out = await pify(gm(image.data).size.bind(gm))();
console.log("gm output: " + out.width);
---
  1 failed

  resize-jpeg › Resize JPEG with jpegoptim
  Error: Cannot read property 'size' of undefined
    proto.(anonymous function) (node_modules/gm/lib/getters.js:47:20)
    node_modules/pify/index.js:29:7
    node_modules/pify/index.js:12:10
    ret (node_modules/pify/index.js:56:34)
    Test.<anonymous> (test/resize-jpeg.js:37:20)
    Generator.next (<anonymous>)

const out = await pify(gm(image.data)).size();
console.log("gm output: " + out.width);
---
  1 failed

  resize-jpeg › Resize JPEG with jpegoptim
  Error: pify(...).size is not a function
    Test.<anonymous> (test/resize-jpeg.js:37:43)
    Generator.next (<anonymous>)

So, my question is: if it’s possible to pify gm and if so, I would like to know how?

[schnittstabil]

Btw, bind-all provides the same functionality as my bind helper above:

const bindAll = require('bind-all');

const gmP = (...args) => pify(bindAll(gm(...args)));

test("Resize JPEG with cjpeg", async t => {
    //…
    const out = await gmP(destPath).size();
    t.is(out.width, 200);
});

[kdybicz]

Thanks to your advice I did end up with code, that is working perfectly fine! https://github.com/secretescapes/aws-lambda-image/blob/improving-tests-quality-v2/test/resize-jpeg.js