FileReader never throws errors

[tpuida]

Describe the bug

const reader = new FileReader();
reader.readAsDataURL(file);

reader.onload = function () {
  resolve(reader.result);
  };
reader.onerror = function (error) {
  reject(error); // never goes here
};

The following test failed:

it('should reject with an error when passed an invalid file', async () => {
    const invalidFile = {};
    await expect(fileToBase64(invalidFile)).rejects.toThrowError();
  });
  
  - Expected: 
[Error: rejected promise]

+ Received: 
"data:application/octet-stream;base64,"

Expected behavior
To throw an error. For example, Mozilla throws the error:
Uncaught TypeError: FileReader.readAsDataURL: Argument 1 does not implement interface Blob.

Screenshots

Device:

• OS: MacOS 14.6.1
• Browser Mozilla
• Version 15.7.4

Additional context
Vitest tests.
The test provided passes on jsdom environment