Babel-plugin: Unrelated files are being bundled together due to import with identical relative paths

🐛 Bug Report

When using the babel-plugin, two different, unrelated, modules having the same filename, and being imported with an identical relative path from different components, end up being bundled together.

For instance, consider this directory structure:

└─ component-1
   ├── index.js
   └── later.js

└─ component-2
   ├── index.js
   └── later.js

If both component-1 and component-2 are using @loadable/component to import their respective later.js module like so:

const Content = loadable(() => import('./later.js'));

We end up with the content of both later.js files bundled in a single later-bundle-[hash].js file. Since these components have nothing in common (except a naming scheme), this is not desirable and seems like a bug to me.

My guess would be that this is due/related to the chunkName being later.js for both.

Changing the imports and filenames to import('./later-1.js) and import('./later-2.js) properly creates two independent modules, not being bundled together.

To Reproduce

Clone this fork quentind/loadable-components and run the modified “server side rendering” example with:

cd examples/server-side-rendering
yarn
yarn build

This will result in the following assetsByChunkName in the loadable-stats.json:

"vendors~letters-A~letters-B~moment": "vendors~letters-A~letters-B~moment-bundle-ebaf5b04.js",
"letters-test-1": "letters-test-1-bundle-6904889d.js",
"letters-test-2": "letters-test-2-bundle-a6f9fa21.js",
"letters-A": [
    "letters-A.css",
    "letters-A-bundle-741365d5.js"
],
"letters-B": "letters-B-bundle-22ea974d.js",
"letters-C": "letters-C-bundle-ac34183c.js",
"letters-D": "letters-D-bundle-5855063f.js",
"letters-E": "letters-E-bundle-0a9b3a90.js",
"letters-F": "letters-F-bundle-0d5ffdb3.js",
"letters-G": "letters-G-bundle-8e463824.js",
"letters-Z-file": "letters-Z-file-bundle-51e385c3.js",
"letters-test-1-content": "letters-test-1-content-bundle-08c48f90.js",
"letters-test-2-content": "letters-test-2-content-bundle-22007c7e.js",
"Y-file": "Y-file-bundle-3e89611f.js",
"content": "content-bundle-16c508f6.js",
"letters-A-css": [
    "letters-A-css.css",
    "letters-A-css-bundle-d5cf68fd.js"
],
"main": [
    "main.css",
    "main-bundle-efe2b3de.js"
],
"moment": "moment-bundle-7128bd13.js"

Notice the "content": "content-bundle-16c508f6.js" file which contains both modules imported as import('./content.js') (not desirable).

Expected behavior

Following the reproduction method described above, I would expect ./letters/test-1/content.js and ./letters/test-2/content.js to NOT be bundled together, allowing them to be loaded separately and only when necessary.

Link to repl or repo (highly encouraged)

quentind/loadable-components See “To reproduce” for instructions.

Run npx envinfo --system --binaries --npmPackages @loadable/component,@loadable/server,@loadable/webpack-plugin,@loadable/babel-plugin --markdown --clipboard

## System:
 - OS: macOS 10.15.2
 - CPU: (16) x64 Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz
 - Memory: 109.27 MB / 16.00 GB
 - Shell: 5.7.1 - /bin/zsh
## Binaries:
 - Node: 10.18.1 - ~/.nvm/versions/node/v10.18.1/bin/node
 - Yarn: 1.21.1 - /usr/local/bin/yarn
 - npm: 6.13.4 - ~/.nvm/versions/node/v10.18.1/bin/npm
## npmPackages:
 - @loadable/babel-plugin: ^5.10.3 => 5.12.0
 - @loadable/component: ^5.10.3 => 5.12.0
 - @loadable/server: ^5.10.3 => 5.12.0
 - @loadable/webpack-plugin: ^5.7.1 => 5.12.0

Please let me know if I can help clarify this in any way. Thanks !

[theKashey]

This is a bug

[kaysonwu]

ah！Or use webpackChunkName to distinguish.

const Content = loadable(() => import(/* webpackChunkName: "page1-content" */ './content.js'))