File Reader

[mirinio]

Describe the bug
I am running into issues with FileReader when running my jest tests.
This happens when I reference happy-dom jest-environment.
testEnvironment: '@happy-dom/jest-environment',

I get following error running a test for a pure function:

reader.readAsDataURL is not a function
TypeError: reader.readAsDataURL is not a function

the funcrion I am testing:

export function convertBlobToBase64(blob: Blob): Observable<string> {
    const reader = new FileReader();
>  reader.readAsDataURL(blob);
    return fromEvent(reader, 'load').pipe(map(() => (reader.result as string).split(',')[1]));
}

To Reproduce
Steps to reproduce the behavior:

1. Reference testEnvironment: '@happy-dom/jest-environment' in your test setup.
2. Write a jest test including FileReader.
3. Run the reader.readAsDataURL(..) function
4. See error

Expected behavior
FileReader should have a readAsDataURL function.

Screenshots
If applicable, add screenshots to help explain your problem.

Device:

• OS: Windows
• Browser Chrome

Additional context
I am working with an Angular project writing jest tests for util functions.