Bug report

What is the current behavior?

In a complex project we are applying multiple loaders - everything works as expected, however when a HMR build triggers the emitted hot-update.json file has a too long name.

[webpack-cli] [Error: ENAMETOOLONG: name too long, open '/Users/rigor789/Code/_tmp/myVueApp/platforms/ios/myVueApp/app/_node_modules_nativescript_webpack_dist_loaders_nativescript-hot-loader_index_js_ruleSet_1_rules_8_use_0_node_modules_babel-loader_lib_index_js_clonedRuleSet-3_0_rules_0_use_0_node_modules_nativescript_webpack_dist_loaders_nativescript-worker-loader_index_js_app_app_js_10_17-67.hot-update.json'] {
  errno: -63,
  code: 'ENAMETOOLONG',
  syscall: 'open',
  path: '/Users/rigor789/Code/_tmp/myVueApp/platforms/ios/myVueApp/app/_node_modules_nativescript_webpack_dist_loaders_nativescript-hot-loader_index_js_ruleSet_1_rules_8_use_0_node_modules_babel-loader_lib_index_js_clonedRuleSet-3_0_rules_0_use_0_node_modules_nativescript_webpack_dist_loaders_nativescript-worker-loader_index_js_app_app_js_10_17-67.hot-update.json'
}

I have tried changing config.output.otUpdateMainFilename & config.output.hotUpdateChunkFilename however if I remove the [runtime] placeholder - the filenames are no longer unique (and webpack warns about this correctly).

If the current behavior is a bug, please provide the steps to reproduce.

Tried to reproduce in a simple scenario but that has proven difficult - as it’s a combination of multiple plugins & loaders.

What is the expected behavior?

The HotModuleReplacementPlugin (or anywhere, if there’s a better place) should handle too long filenames, and shorten them.

Adding some logging, the runtime is the long part that causes trouble: https://github.com/webpack/webpack/blob/e643b85a6accde7e4c7f19c8770816e5aaf6a945/lib/HotModuleReplacementPlugin.js#L454-L463

This seems to be handled for imported chunks already: https://github.com/webpack/webpack/issues/6426

Other relevant information: webpack version: 5.25.0 Node.js version: 14.9.0 Operating System: macOS Additional tools: N/A