Parcel (the transformer?) does not recover after an error in an imported AS file

[dipdowel]

Summary

Either Parcel or the transformer does not recover after an error occurs in an AssemblyScript file imported in index.as.ts

Steps to reproduce

1. Clone the project template
2. Change directory to assemblyscript-parcel-template
3. yarn or npm install
4. yarn start or npm run start
5. Open http://localhost:1234/ in your browser
6. Open assembly/index.as.ts in your IDE
7. After line const result = add16bit(<i16>a, <i16>b); insert const t: i32;
8. Save and observer the error in the terminal and in your browser console
9. Remove line const t: i32; from assembly/index.as.ts and save the file.

State at this point

Parcel should successfully recompile your AS code and the error message should disappear form the terminal and from the browser console.

11. Open assembly/helpers/add-16bit.ts in your IDE
12. Before line return a + b; insert const t: i32;
13. Save and observer the error in the terminal and in your browser console
14. Remove line const t: i32; from assembly/helpers/add-16bit.ts and save the file.

Expected result

Parcel should successfully recompile your AS code and the error message should disappear form the terminal and from the browser console.

Actual result

Parcel does not seem to detect the change in assembly/helpers/add-16bit.ts, the error message remains in the terminal and in the browser console. Please see the screenshot below:

A work-around

If you then make any change in index.as.ts and save it, the project will be recompiled and reloaded as expected.

[mischnic]

Currently, you do:

• Run the ASC compiler
• if there's an error, throw
• add the file invalidations, call asset.setCode, ...

Instead, you need to

• Run the ASC compiler
• add the file invalidations
• if there's an error, throw
• call asset.setCode, ...

E.g. https://github.com/mischnic/parcel-transformer-assemblyscript-codument/commit/420cd42c1c63e105bd4c6ef18902e856b9cc08e3

[dipdowel]

Currently, you do:

E.g. mischnic@420cd42

Hey @mischnic, thanks a lot for the suggested solution, it did the trick! Also, thank you so much for improving the quality of the code that surrounded your changes.
Here's the merged PR with your suggestion: #9