Bug Report

Current Behavior
Babel ignores input source maps.

Input Code
https://github.com/dkamyshov/babel-input-source-map-reproduction

• run yarn, you should see {"version":3,"sources":["../lib-tmp/index.js"],... in the console - this is incorrect

• run yarn add -D @babel/core@7.5.5. you should see {"version":3,"sources":["../src/index.tsx"],... - this is correct

Expected behavior/code
Babel should consume input source maps and reference original source files in the resulting source maps.

Babel Configuration (.babelrc, package.json, cli command)

{
  "sourceMaps": true,
  "inputSourceMap": true,
  "presets": ["@babel/preset-env"]
}

babel lib-tmp --out-dir lib --extensions .js --source-maps

Environment

• Babel version(s): 7.6.3 (@babel/core 7.6.3)
• Node/npm version: v10.16.0, 6.9.0
• OS: OSX 10.14.6
• Monorepo: no
• How you are using Babel: cli

Possible Solution
Downgrade to v7.5.5 or earlier.