getOffsetFromResponse isn't behaving quite right

[JohnHayford]

in uploaderx.ts, getOffsetFromResponse doesn't seem to be behaving quite right for the following use cases.
Missing Range: this should be allowed, using the same Google Doc upload reference (https://developers.google.com/drive/api/v3/manage-uploads#resume-upload) that you are using. This should tell the service that no content has been received and to start at byte 0.

"Range: bytes=0-1" : This will get matched as "-1" and will send from byte 0. There's not really a standard on using the Range header on a response, so not sure of what the right answer is. Possible solution would be looking for two dashes when matching "-1", ie, "-1--1" for no content. /(--1|\d+)$/g
Also looking for just "-1", like "Range: bytes=-1" could work.

https://github.com/kukhariev/ngx-uploadx/blob/master/src/uploadx/src/uploaderx.ts

[kukhariev]

I think it'll work 🛴

ngx-uploadx/src/uploadx/src/uploaderx.spec.ts

Lines 27 to 43 in 484729d

	describe('getRangeEnd', () => {
	it('invalid ranges', () => {
	expect(getRangeEnd(undefined)).toEqual(-1);
	expect(getRangeEnd('')).toEqual(-1);
	expect(getRangeEnd('-invalid-')).toEqual(-1);
	expect(getRangeEnd('Range: bytes=-1')).toEqual(-1);
	expect(getRangeEnd('Range: bytes=-5')).toEqual(-1);
	expect(getRangeEnd('Range: bytes=0--5')).toEqual(-1);
	expect(getRangeEnd('Range: bytes=0--1')).toEqual(-1);
	});
	it('valid ', () => {
	expect(getRangeEnd('Range: bytes=0-1')).toEqual(1);
	expect(getRangeEnd('Range: bytes=0-0')).toEqual(0);
	expect(getRangeEnd('Range: bytes=0-100')).toEqual(100);
	});
	});