Consts still in bundle even though using babel env preset safari >= 7

Question

I have a client that has employees working on older iPads and they can't update their safari versions to 10.x+ so they're stuck w/ safari 9.x. And I keep getting the following error when I try to load my browser app in Safari 9.x on an iPad:

SyntaxError: Unexpected keyword 'const'. Const declarations are not supported in strict mode.

I'm using babel-loader in my webpack config and I have the following babel options that I'm setting on the loader's options property:

 { presets: [ [ "env", { targets: { browsers: ["last 3 versions", "safari >= 8"] }, debug: true } ], // `es2015`, `stage-1` ], retainLines: true, plugins: [ "syntax-jsx", "transform-react-jsx", "transform-react-display-name", "transform-react-require", "transform-es2015-destructuring", "transform-es2015-parameters", "transform-object-rest-spread", "transform-class-properties", // "check-es2015-constants", // "transform-es2015-block-scoping", ["transform-runtime", { "polyfill": false, "regenerator": true }] ] } 

In my console when I do the build, it EVEN SAYS:

Using targets:
{
  "chrome": "59",
  "android": "4.4",
  "edge": "13",
  "firefox": "54",
  "ie": "9",
  "ios": "10",
  "safari": "8"
}

And:

Using plugins:
  check-es2015-constants {"android":"4.4","edge":"13","ie":"9","safari":"8"}
  transform-es2015-block-scoping {"android":"4.4","edge":"13","ie":"9","safari":"8"}

But there are STILL const declarations (65 to be exact) throughout my bundle. And no, they aren't all node_module imports... Most are my own React component files.

How do I get babel to just replace ALL instances of const w/ var ?

I'm on webpack 3.7.1 and babel-loader 7.1.2 and babel-core 6.26

Answer 1

Turns out I was using a Webpack alias for this project still: https://github.com/njl07/rx-http-request/issues/15#issue-273561398

Apparently babel transformations aren't applied to aliases for some reason.

Updated to the latest package and all is good now.