Scope hoisting/tree shaking bug (--experimental-scope-hoisting)

[sergey-shpak]

🐛 bug report

Bundle missing pragma function used to transform jsx to vnodes.

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

parcel build ./src/app.js --experimental-scope-hoisting --no-minify

Default babel config

🤔 Expected Behavior

Pragma function is not tree shaked from source

😯 Current Behavior

Pragma function removed from bundle

In my case: Uncaught ReferenceError: h is not defined

💁 Possible Solution

Pragma function imported to source, but the function invocation only occurs in the transpiled source
(after babel-plugin-transform-react-jsx transformations), as result pragma function invocations are not visible for tree shaking and they are removed.

🔦 Context

💻 Code Sample

import { h } from 'hyperapp';
export default <div>test</div>;

🌍 Your Environment

Software	Version(s)
Parcel	1.10.1
Node	v8.9.4
npm/Yarn
Operating System

[mischnic]

as result pragma function invocations are not visible for tree shaking

Tree shaking runs after the babel transformations.