erp5_upgrader: do not run activeSense for post-upgrade step

As results may be inconsistent as long as pre-upgrade and upgrade steps have been run for real

bt5/erp5_upgrader/SkinTemplateItem/portal_skins/erp5_upgrader/Alarm_runFullUpgrader.py

@@ -12,6 +12,9 @@ pre_upgrade_tag = '%s-preupgrade' % tag
 upgrade_tag = '%s-upgrade' % tag
 post_upgrade_tag = '%s-postupgrade' % tag
 
+active_process = context.newActiveProcess()
+
+
 portal_alarms.upgrader_check_pre_upgrade.activate(
   activity='SQLQueue',
   tag=pre_upgrade_tag,
@@ -23,15 +26,28 @@ portal_alarms.upgrader_check_upgrader.activate(
   after_tag=pre_upgrade_tag,
  ).activeSense(fixit=fixit, params={'tag': upgrade_tag})
 
-portal_alarms.upgrader_check_post_upgrade.activate(
-  activity='SQLQueue',
-  tag=post_upgrade_tag,
-  after_tag=upgrade_tag,
-).activeSense(fixit=fixit, params={'tag': post_upgrade_tag})
+# If we are not running the real upgrade, not need to run activeSense
+# of the post-upgrade step : post-upgrade constraints will be run on
+# what are *currently* installed, and not on the result of the previous
+# steps, which lead to a wrong and misleading consistency check
+if fixit:
+  portal_alarms.upgrader_check_post_upgrade.activate(
+    activity='SQLQueue',
+    tag=post_upgrade_tag,
+    after_tag=upgrade_tag,
+  ).activeSense(fixit=fixit, params={'tag': post_upgrade_tag})
+else:
+  summary = "Post-upgrade constraints are not run as their results may differ after "
+  summary += "upgrader's alarm is solved. To dry-run post-upgrade alarm, please run the pre-ugprade "
+  summary += "and upgrade steps for real, then run post-upgrade \"Active Sense\" action."
+
+  active_process.postActiveResult(
+  severity=1,
+  summary=summary,
+  detail=[m.message for m in constraint_message_list])
 
 
 # start another activity to collect the results from each upgrader step
-active_process = context.newActiveProcess()
 context.activate(after_tag=post_upgrade_tag).Alarm_postFullUpgradeNeed(
   active_process=active_process.getRelativeUrl())