How to write unit test component with FileReader.addEventListener in angular 8? - karma-jasmine

Question

I use angular 8 and i want to test my component with FileReader.
I can not test a FileReader in my processFile function.
Maybe my work is badly written? Can you help me please to understand.
IF I understand correctly, I have to test a class (Filereader) in a process function
my component
processFile(imageInput: any) {
const file: File = imageInput.files[0];
const reader = new FileReader();
let size: number = 2097152
if (file) {
if (file.size <= size) {
this.sharingDataService.setUploadIsOk(true)
reader.addEventListener('progress', (event:any) =>{
this.progressValue = this.progressBar(event)
if (event.lengthComputable) {
// console.log(event.loaded+ " / " + event.total)
}
})
reader.addEventListener('loadstart', (event:any) =>{
this.progressValue =0;
this.textDuringUploadBefore = "No"
this.textDuringUploadAfter = ''
// console.log('start');
})
reader.addEventListener('loadend', (event:any) =>{
// console.log('end');
})
reader.addEventListener('load', (event: any) => {
console.log(event);
this.selectedFile = new ImageSnippet(event.target.result, file);
this.fileName = this.selectedFile.file.name;
this.fileNameExt =this.fileName.split('.').pop();
this.displayAddPhoto = false;
this.selectedFile.status = 'ok';
this.getLoadCallBack(file)
// this.ng2ImgMax.resizeImage(file, 900,600).subscribe(
// result =>{
// // console.log('compress', );
// this.textDuringUploadAfter= "Yes!!!"
// this.textDuringUploadBefore= ''
// this.fileForm.patchValue({
// image: new File([result], result.name)
// });
// this.imageIsLoad = true
// this.sharingDataService.setUploadIsOk(false)
// }
// )
// this.imageOutput.emit(this.fileForm)
});
reader.readAsDataURL(file);
} else {
const msg ="This picture is too big."
+ '<br/>' + "Please upload an image of less than 2MB."
// this.sharedFunctionService.openDialogAlert(msg, 'home')
this.errorService.openDialogError(msg)
this.imageIsLoad = false
this.sharingDataService.setUploadIsOk(false)
}
}
}
getLoadCallBack(file:File){
this.ng2ImgMax.resizeImage(file, 900,600).subscribe(
result =>{
// console.log('compress', );
this.textDuringUploadAfter= "Yes"
this.textDuringUploadBefore= ''
this.fileForm.patchValue({
image: new File([result], result.name)
});
console.log(this.fileForm);
this.imageIsLoad = true
this.sharingDataService.setUploadIsOk(false)
}
)
this.imageOutput.emit(this.fileForm)
}
my spec.ts
it('processFile', () => {
// const mockEvt = { target: { files: [fileInput] } };
// const mockReader: FileReader = jasmine.createSpyObj('FileReader', ['readAsDataURL', 'onload']);
// spyOn(window as any, 'FileReader').and.returnValue(mockReader);
// spyOn(component, 'getLoadCallBack').and.callThrough();
const file = new File([''], 'test-file.jpg', { lastModified: null, type: 'image/jpeg' });
const fileInput = { files: [file] };
const eventListener = jasmine.createSpy();
spyOn(window as any, "FileReader").and.returnValue({
addEventListener: eventListener
})
component.processFile(fileInput);
i have got an error
TypeError: reader.readAsDataURL is not a function
how to test my processFile function?
I trie many way but no sucess