let variable renaming and function.name bug

[theshock]

Bug Report

Current Behavior
Sometimes variable renaming leads to wrong behavior. In this example:

let x = () => {};

{
  let x = () => {};

  console.log(x.name);
}

The compiler result will be:

"use strict";

var x = function x() {};

{
  var _x = function _x() {};

  console.log(_x.name);
}

And the output will be _x instead of correct x

Environment

• Babel version(s): 7.3.3
• Node/npm version: 8.9
• How you are using Babel: babeljs.io/repl

Possible Solution
Compile let using closure instead of renaming

[babel-bot]

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