UniqueBarcodeHandler is broken due to supplier item matching

[ius]

Logic for assigning custom barcodes uses UniqueBarcodeHandler prior to actually linking the barcode to check whether a barcode is already in use.

inventree-app/lib/barcode/barcode.dart

Lines 383 to 396 in 9745bcf

	var handler = UniqueBarcodeHandler((String barcode) {
	InvenTreeAPI().linkBarcode({
	model: pk.toString(),
	"barcode": barcode,
	}).then((bool result) {
	showSnackIcon(
	result ? L10().barcodeAssigned : L10().barcodeNotAssigned,
	success: result
	);
	state.refresh(context);
	});
	});
	scanBarcode(context, handler: handler);

This uses the /api/barcode/ endpoint which may in fact also return results due to the barcode being parsed and having an existing supplier item returned instead of the barcode actually being in use.

To reproduce: make sure a supplier item exists for a EIGP 114.2018 barcode (e.g. DigiKey/Mouser) then attempt to assign the barcode to a stock item.

I think this bug might be the cause of inventree/InvenTree#7637

Additional information
App version: 0.17.0 (built from source + patched for #570)
Flutter: 3.24.5

[SchrodingersGat]

@ius nice catch - can you look into providing a patch for this?

[SchrodingersGat]

@ius I should have a fix a part of #577 - can you please test on your end and see if the issue is actually fixed?

[ius]

Was finally able to test this - works great! Thanks for the quick fix!