feat(package): update to Babel 7 (beta)

[ybiquitous]

Update process

# Uninstall old packages
yarn remove babel-{cli,preset-env,register,plugin-transform-object-rest-spread}

# Install new packages
yarn add --dev @babel/{cli,core,preset-env,register}

Notes

• babel-plugin-istanbul doesn't depend on Babel packages, so no problem without changes 😄

• Remove babel-plugin-transform-object-rest-spread because @babel/preset-env installs @babel/plugin-proposal-object-rest-spread 😄

• Don't remove @babel/plugin-proposal-object-rest-spread from .babelrc, otherwise tests fail 😕

Command details

$ git diff
diff --git a/.babelrc b/.babelrc
index 4c2e056..8bbff1c 100644
--- a/.babelrc
+++ b/.babelrc
@@ -3,7 +3,6 @@
     ["@babel/preset-env", {"targets": {"node": "6"}}]
   ],
   "plugins": [
-    "@babel/plugin-proposal-object-rest-spread"
   ],
   "env": {
     "test": {

$ yarn test
yarn run v1.3.2
$ nyc --check-coverage mocha
/Users/koba/git/ybiq/node_modules/@babel/core/lib/transformation/normalize-file.js:136
    throw err;
    ^

SyntaxError: /Users/koba/git/ybiq/test/helpers/exec.js: Support for the experimental syntax 'objectRestSpread' isn't currently enabled (8:12):

   6 | export default function exec(...args) {
   7 |   const options = {
>  8 |     env: { ...process.env, LANG: 'C' },
     |            ^
   9 |   }
  10 |   return new Promise((resolve, reject) => {
  11 |     cp.execFile(tested, args, options, (error, stdout, stderr) => {

Add @babel/plugin-proposal-object-rest-spread (https://git.io/vb4Ss) to the 'plugins' section of your Babel config to enable transformation.
    at Parser.raise (/Users/koba/git/ybiq/node_modules/@babel/core/node_modules/babylon/lib/index.js:832:15)
    at Parser.expectPlugin (/Users/koba/git/ybiq/node_modules/@babel/core/node_modules/babylon/lib/index.js:2217:18)
    at Parser.parseObj (/Users/koba/git/ybiq/node_modules/@babel/core/node_modules/babylon/lib/index.js:3679:14)
    at Parser.parseExprAtom (/Users/koba/git/ybiq/node_modules/@babel/core/node_modules/babylon/lib/index.js:3310:21)
    at Parser.parseExprSubscripts (/Users/koba/git/ybiq/node_modules/@babel/core/node_modules/babylon/lib/index.js:2972:21)
    at Parser.parseMaybeUnary (/Users/koba/git/ybiq/node_modules/@babel/core/node_modules/babylon/lib/index.js:2950:21)
    at Parser.parseExprOps (/Users/koba/git/ybiq/node_modules/@babel/core/node_modules/babylon/lib/index.js:2855:21)
    at Parser.parseMaybeConditional (/Users/koba/git/ybiq/node_modules/@babel/core/node_modules/babylon/lib/index.js:2825:21)
    at Parser.parseMaybeAssign (/Users/koba/git/ybiq/node_modules/@babel/core/node_modules/babylon/lib/index.js:2781:21)
    at Parser.parseObjectProperty (/Users/koba/git/ybiq/node_modules/@babel/core/node_modules/babylon/lib/index.js:3817:101)
...