GatedClocks-bugfix: Fixed bug in gated clocks feature

We previously only checked that instructions on clocklines were not too close together for the clock limit (i.e. was an instruction on clockline A too close to the next instruction on clockline A, and was instruction B too close to the next instruction on clockline B). However, this does not catch the case where an instruction on clockline B is close to an instruction on clockline A, thus forcing the pulse on clockline A to be shorter than it would otherwise.

This case is now caught in the below patch.

labscript.py

@@ -653,12 +653,24 @@ def collect_change_times(self, all_outputs, outputs_by_clockline):
             # Get rid of duplicates if trigger times were already in the list:
             change_time_list = list(set(change_time_list))
             change_time_list.sort()
-
+
+            # index to keep track of in all_change_times
+            j = 0
             # Check that no two instructions are too close together:
             for i, t in enumerate(change_time_list[:-1]):
                 dt = change_time_list[i+1] - t
                 if dt < 1.0/clock_line.clock_limit:
-                    raise LabscriptError('Commands have been issued to devices attached to %s at t= %s s and %s s. '%(self.name, str(t),str(change_time_list[i+1])) +
+                    raise LabscriptError('Commands have been issued to devices attached to clockline %s at t= %s s and %s s. '%(clock_line.name, str(t),str(change_time_list[i+1])) +
+                                         'One or more connected devices on ClockLine %s cannot support update delays shorter than %s sec.'%(clock_line.name, str(1.0/clock_line.clock_limit)))
+
+                # increment j until we reach the current time
+                while all_change_times[j] < t and j < len(all_change_times)-1:
+                    j += 1
+                # j should now index all_change_times at "t"
+                # Check that the next all change_time is not too close (and thus would force this clock tick to be faster than the clock_limit)
+                dt = all_change_times[j+1] - t
+                if dt < 1.0/clock_line.clock_limit:
+                    raise LabscriptError('Commands have been issued to devices attached to %s at t= %s s and %s s. '%(self.name, str(t),str(all_change_times[j+1])) +
                                          'One or more connected devices on ClockLine %s cannot support update delays shorter than %s sec.'%(clock_line.name, str(1.0/clock_line.clock_limit)))
 
             # Also add the stop time as as change time. First check that it isn't too close to the time of the last instruction: