[ADD] migrate from 8.0 if possible in init hook

account_payment_mode/hooks.py

@@ -0,0 +1,26 @@
+# -*- coding: utf-8 -*-
+# © 2016 Therp BV <http://therp.nl>
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
+
+
+def pre_init_hook(cr):
+    migrate_from_8(cr)
+
+
+def migrate_from_8(cr):
+    """If we're installed on a database which has the payment_mode table
+    from 8.0, move its table so that we use the already existing modes"""
+    cr.execute("SELECT 1 FROM pg_class WHERE relname = 'payment_mode'")
+    if not cr.fetchone():
+        return
+    try:
+        from openupgradelib.openupgrade import rename_models
+        rename_models(cr, [('payment.mode', 'account.payment.mode')])
+    except ImportError:
+        cr.execute('ALTER TABLE payment_mode RENAME TO account_payment_mode')
+        cr.execute('ALTER SEQUENCE payment_mode_id_seq '
+                   'RENAME TO account_payment_mode_id_seq')
+    cr.execute(
+        'ALTER TABLE account_payment_mode '
+        'RENAME COLUMN journal TO fixed_journal_id'
+    )