Fix zxingcpp position handling: support non-iterable Position by reading corner attributes; prevent 'Position is not iterable'

pdf_comparator.py

@@ -857,14 +857,43 @@ def _decode_zxing(pil: Image.Image) -> List[Dict[str,Any]]:
     arr = np.asarray(pil.convert("L"))
     out=[]
     for r in zxingcpp.read_barcodes(arr):  # try_harder is default True in recent builds; otherwise supply options
-        pts = r.position or []
+        # zxingcpp.Position may be iterable (sequence of points) or an object with corner attributes
+        x1=y1=x2=y2=w=h=0
+        pos = getattr(r, "position", None)
+        pts: List[Any] = []
+        if pos is not None:
+            try:
+                pts = list(pos)  # works if iterable
+            except TypeError:
+                # Fall back to known corner attribute names across versions
+                corner_names = (
+                    "top_left", "topLeft",
+                    "top_right", "topRight",
+                    "bottom_left", "bottomLeft",
+                    "bottom_right", "bottomRight",
+                    "point1", "point2", "point3", "point4",
+                )
+                seen=set()
+                for name in corner_names:
+                    if hasattr(pos, name):
+                        p = getattr(pos, name)
+                        # avoid duplicates
+                        if id(p) not in seen and hasattr(p, "x") and hasattr(p, "y"):
+                            pts.append(p)
+                            seen.add(id(p))
         if pts:
-            xs=[p.x for p in pts]; ys=[p.y for p in pts]
-            x1,x2=int(min(xs)),int(max(xs)); y1,y2=int(min(ys)),int(max(ys))
+            xs=[int(getattr(p, "x", 0)) for p in pts]
+            ys=[int(getattr(p, "y", 0)) for p in pts]
+            x1,x2=min(xs),max(xs); y1,y2=min(ys),max(ys)
             w,h=x2-x1,y2-y1
-        else:
-            x1=y1=w=h=0
-        out.append({"type": str(r.format), "data": r.text or "", "left": x1, "top": y1, "width": w, "height": h})
+        out.append({
+            "type": str(r.format),
+            "data": r.text or "",
+            "left": x1,
+            "top": y1,
+            "width": w,
+            "height": h,
+        })
     return out
 
 def _decode_zbar(pil: Image.Image) -> List[Dict[str,Any]]: