[IMP] mis_builder: recompute on ValueError

so kpi can be displayed in an other sequence than the computation dependency order

mis_builder/models/mis_builder.py

@@ -622,7 +622,10 @@ class mis_report_instance_period(orm.Model):
         localdict.update(self._fetch_queries(cr, uid, c,
                                              context=context))
 
-        for kpi in c.report_instance_id.report_id.kpi_ids:
+        compute_queue = c.report_instance_id.report_id.kpi_ids
+        recompute_queue = []
+        while True:
+            for kpi in compute_queue:
                 try:
                     kpi_val_comment = kpi.expression
                     kpi_eval_expression = aep.replace_expr(kpi.expression)
@@ -631,6 +634,11 @@ class mis_report_instance_period(orm.Model):
                     kpi_val = None
                     kpi_val_rendered = '#DIV/0'
                     kpi_val_comment += '\n\n%s' % (traceback.format_exc(),)
+                except ValueError:
+                    recompute_queue.append(kpi)
+                    kpi_val = None
+                    kpi_val_rendered = '#ERR'
+                    kpi_val_comment += '\n\n%s' % (traceback.format_exc(),)
                 except:
                     kpi_val = None
                     kpi_val_rendered = '#ERR'
@@ -660,6 +668,18 @@ class mis_report_instance_period(orm.Model):
                     'period_name': c.name,
                 }
 
+            if len(recompute_queue) == 0:
+                # nothing to recompute, we are done
+                break
+            if len(recompute_queue) == len(compute_queue):
+                # could not compute anything in this iteration
+                # (ie real Value errors or cyclic dependency)
+                # so we stop trying
+                break
+            # try again
+            compute_queue = recompute_queue
+            recompute_queue = []
+
         return res