Upgrade babel to v7.2
Upgrades babel and all plugins to the latest version
Babel 7.2 release blog post here: https://babeljs.io/blog/2018/12/03/7.2.0
The primary notable change here apart from bug fixes and preset-env stat updates is the inclusion of @babel/plugin-proposal-private-methods
which has now reached stage-3 proposal status.
Since we are enabling all stage-3 proposals, we now support class private methods and with the #
prefix (spec here):
class Person {
#age = 19;
#increaseAge() {
this.#age++;
}
birthday() {
this.#increaseAge();
alert("Happy Birthday!");
}
}