ES2015ify the gulpfile

[sindresorhus]

Nicer syntax. Less code. Why not.

Gulp and Babel handles this for us. It just works.

// @addyosmani @surma

[surma]

Love it! Will take a closer look at the code shorty.

Drone is failing because it looks like we need to tweak the customizer to play well with this setup, something we wanted to do anyways. We should probably do that in a separate PR.

Does JSCS/JSHint have ES6 enabled already or is linting going to fail?

[sindresorhus]

Does JSCS/JSHint have ES6 enabled already or is linting going to fail?

JSCS parses ES2015 by default. .jshintrc has the esnext: true option set.

[addyosmani]

Code reviewed and changes LGTM. We just need to nail down the issues around Drone failing:

[14:52:19] ReferenceError: MaterialCustomizer is not defined
    at Object.<anonymous> (/var/cache/drone/src/github.com/google/material-design-lite/docs/_assets/customizer.js:71:19)
    at Module._compile (module.js:456:26)
    at normalLoader (/cache/node_modules/babel-core/lib/api/register/node.js:199:5)
    at Object.require.extensions.(anonymous function) [as .js] (/cache/node_modules/babel-core/lib/api/register/node.js:216:7)
    at Module.load (module.js:356:32)
    at Function.Module._load (module.js:312:12)
    at Module.require (module.js:364:17)
    at require (module.js:380:17)
    at Gulp.<anonymous> (/var/cache/drone/src/github.com/google/material-design-lite/gulpfile.babel.js:759:30)
    at module.exports (/cache/node_modules/gulp/node_modules/orchestrator/lib/runTask.js:34:7)
[14:52:19] 'all' errored after 37 s
[14:52:19] ReferenceError: MaterialCustomizer is not defined
    at Object.<anonymous> (/var/cache/drone/src/github.com/google/material-design-lite/docs/_assets/customizer.js:71:19)
    at Module._compile (module.js:456:26)
    at normalLoader (/cache/node_modules/babel-core/lib/api/register/node.js:199:5)
    at Object.require.extensions.(anonymous function) [as .js] (/cache/node_modules/babel-core/lib/api/register/node.js:216:7)
    at Module.load (module.js:356:32)
    at Function.Module._load (module.js:312:12)
    at Module.require (module.js:364:17)
    at require (module.js:380:17)
    at Gulp.<anonymous> (/var/cache/drone/src/github.com/google/material-design-lite/gulpfile.babel.js:759:30)
    at module.exports (/cache/node_modules/gulp/node_modules/orchestrator/lib/runTask.js:34:7)

Personal preference is that we figure out what needs to be updated in the Customiser to make it play well with this setup prior to landing this change. Other team members are working against master so we probably want to avoid breaking their workflow prematurely :)

[sindresorhus]

Figured out the issue. The Drone is now passing.

The problem was that the Babel require hook hooks all requires, so it tried to ES2015ify the "docs/_assets/customizer.js" file, which didn't work. It will now only transpile the gulpfile: https://github.com/google/material-design-lite/pull/1677/files#diff-b9cfc7f2cdf78a7f4b91a753d10865a2R79

[addyosmani]

Fantastic. Thanks once again for the PR, @sindresorhus! 🐴 ✨ 😍

[surma]

🎉