scannable: fix RangeScan randomize seeding

artiq/gui/entries.py

@@ -361,6 +361,7 @@ class ScanEntry(LayoutWidget):
                     state[ty]["stop"] = default["stop"]
                     state[ty]["npoints"] = default["npoints"]
                     state[ty]["randomize"] = default["randomize"]
+                    state[ty]["seed"] = default["seed"]
                 elif ty == "ExplicitScan":
                     state[ty]["sequence"] = default["sequence"]
                 else:

artiq/language/scan.py

@@ -78,9 +78,8 @@ class RangeScan(ScanObject):
             self.sequence = [i*dx + start for i in range(npoints)]
 
         if randomize:
-            if seed is not None:
-                random.seed(seed)
-            random.shuffle(self.sequence)
+            rng = random.Random(seed)
+            random.shuffle(self.sequence, rng.random)
 
     @portable
     def __iter__(self):