Watch breaks application start

[JonasHelming]

Create a template, e.g. hello world
yarn watch on the root level
change something
wait until the rebuild finishes
cd browser-app & yarn start

=> /home/jonas/tmp/theiatest/generatechangebuild/browser-app/lib/backend/vendors-node_modules_drivelist_build_Release_drivelist_node-node_modules_stroncium_procfs_lib-0ccbd3.js:16
throw new Error('node-loader:\n' + error);
^

Error: node-loader:
Error: Module did not self-register: '/home/jonas/tmp/theiatest/generatechangebuild/browser-app/lib/backend/native/drivelist.node'.
at Object.../node_modules/drivelist/build/Release/drivelist.node (/home/jonas/tmp/theiatest/generatechangebuild/browser-app/lib/backend/vendors-node_modules_drivelist_build_Release_drivelist_node-node_modules_stroncium_procfs_lib-0ccbd3.js:16:9)
at webpack_require (/home/jonas/tmp/theiatest/generatechangebuild/browser-app/lib/backend/main.js:667:42)
at module.exports (/home/jonas/tmp/theiatest/generatechangebuild/browser-app/lib/backend/main.js:155:34)
at Object.../node_modules/drivelist/js/index.js (/home/jonas/tmp/theiatest/generatechangebuild/browser-app/lib/backend/vendors-node_modules_drivelist_build_Release_drivelist_node-node_modules_stroncium_procfs_lib-0ccbd3.js:30872:27)
at webpack_require (/home/jonas/tmp/theiatest/generatechangebuild/browser-app/lib/backend/main.js:667:42)
at Object.../node_modules/@theia/core/lib/node/env-variables/env-variables-server.js (/home/jonas/tmp/theiatest/generatechangebuild/browser-app/lib/backend/vendors-node_modules_drivelist_build_Release_drivelist_node-node_modules_stroncium_procfs_lib-0ccbd3.js:5204:19)
at webpack_require (/home/jonas/tmp/theiatest/generatechangebuild/browser-app/lib/backend/main.js:667:42)
at Object.../node_modules/@theia/core/lib/node/env-variables/index.js (/home/jonas/tmp/theiatest/generatechangebuild/browser-app/lib/backend/vendors-node_modules_drivelist_build_Release_drivelist_node-node_modules_stroncium_procfs_lib-0ccbd3.js:5313:14)
at webpack_require (/home/jonas/tmp/theiatest/generatechangebuild/browser-app/lib/backend/main.js:667:42)
at Object.../node_modules/@theia/core/lib/node/backend-application-module.js (/home/jonas/tmp/theiatest/generatechangebuild/browser-app/lib/backend/vendors-node_modules_drivelist_build_Release_drivelist_node-node_modules_stroncium_procfs_lib-0ccbd3.js:4568:25)
Done in 1.19s.

[JonasHelming]

@sdirix do you have an idea here?

[sdirix]

Looking at the scripts the following is happening:

• watch is executed in all packages
• The watch in browser-app and electron-app both trigger rebuild, i.e. theia rebuild:browser and theia rebuild:electron.

The native Node modules can only be built for either browser or electron, not both at the same time. I'm also not sure what happens when both rebuilds are executed in parallel, i.e. whether one of them then "wins" or maybe even both are broken.

drivelist.node is one of the native modules, so yarn start fails for you because it's now the electron version or broken by the parallel watch.

Suggestion: Either

• Don't offer a single watch script in the root, but offer watch:browser and watch:electron, or
• Keep the watch script but only watch the browser variant

[JonasHelming]

I would be in favor of the first option, @vince-fugnitto WDYT?

[vince-fugnitto]

I'd be in favor of separating the watch scripts for each application target (first option).