[2.0 alpha 3.2]TypeError: module.hot is undefined

[andriijas]

🐛 bug report

💻 Code Sample

Reproducible repo: https://github.com/andriijas/parcel-hmr-error

🤔 Expected Behavior

Expect async routes to navigate

😯 Current Behavior

Try open http://localhost:1234/dashboard in browser and then navigate to Foo or Bar in the header navigation

🌍 Your Environment

Software	Version(s)
Parcel
Node	v13.7.0
npm/Yarn	6.13.6
Operating System	macos catalina

🖼 Screenshot

[mischnic]

Minimal Reproduction:

// a.js
import React from "react";
import C from "./c";

function A() {
	return (
		<div>
			A
			<C />
		</div>
	);
}

export default A;

// b.js
import React from "react";
import C from "./c";

function B() {
	return (
		<div>
			B
			<C />
		</div>
	);
}

export default B;

// c.js
import React from "react";

function C() {
	return "Common";
}

export default C;

// index.js
import React, { Suspense, lazy } from "react";
import ReactDOM from "react-dom";

let A = lazy(() => import("./a"));
let B = lazy(() => import("./b"));

export default function App(props) {
	return (
		<Suspense fallback={<p>Loading...</p>}>
			<A />
		</Suspense>
	);
}

ReactDOM.render(<App />, document.getElementById("root"));

[mischnic]

The HMR runtime isn't executed in the async bundle.

// index.js
import React from "react";

let A = () => import("./a");
let B = () => import("./b");

console.log(A().then(v => v.default));

// a.js
import React from "react";
import C from "./c";

console.log("A", module.hot);

export default "A" + C;

// b.js
import React from "react";
import C from "./c";

console.log("B", module.hot);

export default "B" + C;

// c.js
import React from "react";

console.log("C", module.hot); // undefined

export default "C";

[andriijas]

@mischnic is this by design or am I doing async bundling wrong?

[mischnic]

No, this is a bug.