[FIX] pre-upgrade script to preserve module states during merges

Author: nicomacr

pre_upgrade_scripts/180_190/merge_and_renames.py

@@ -44,12 +44,24 @@ def safe_new_module(cr, module, deps=(), *args, **kwargs):
         cr.execute(
             SQL(
                 """
-                UPDATE ir_module_module
-                   SET state = 'to upgrade'
+                SELECT state FROM ir_module_module
                  WHERE name = %(name)s
-                   AND state NOT IN ('installed', 'to install', 'to upgrade')
+                """,
+                name=old,
+            )
+        )
+        old_state = cr.fetchone()
+        old_state = old_state and old_state[0] or "uninstalled"
+        cr.execute(
+            SQL(
+                """
+                UPDATE ir_module_module
+                    SET state = %(upgrade_state)s
+                    WHERE name = %(name)s
+                    AND state NOT IN ('installed', 'to install', 'to upgrade')
                 """,
                 name=into,
+                upgrade_state=old_state,
             )
         )
     for old, into in RENAMED_MODULES: