Allow remove companies in parties when is administrator group

#071843

party.py

@@ -210,6 +210,7 @@ class Party(metaclass=PoolMeta):
     def set_companies_field(cls, parties, name, value):
         pool = Pool()
         PartyCompany = pool.get('party.company.rel')
+        Data = pool.get('ir.model.data')
 
         party_company = PartyCompany.__table__()
         cursor = Transaction().connection.cursor()
@@ -253,7 +254,15 @@ class Party(metaclass=PoolMeta):
                 PartyCompany.create(to_create)
 
         if to_remove:
-            raise UserError(gettext('party_company.can_not_remove_companies'))
+            groups = Transaction().context.get('groups', [])
+            group_admin = Data.get_id('res', 'group_admin')
+            if group_admin not in groups:
+                raise UserError(gettext('party_company.can_not_remove_companies'))
+            to_delete = PartyCompany.search([
+                ('party', 'in', parties),
+                ('company', 'in', to_remove),
+                ])
+            PartyCompany.delete(to_delete)
 
 
 class PartyCompanyMixin(object):

tests/scenario_party_company.rst

@@ -83,3 +83,16 @@ Create new parties::
     True
     >>> party5.companies[0] == company2_user.company
     True
+
+Delete companies in parties::
+
+    >>> party6 = Party()
+    >>> len(party6.companies) == 1
+    True
+    >>> company, = party6.companies
+    >>> party6.companies.remove(company)
+    >>> len(party6.companies) == 0
+    True
+    >>> party6.save()
+    >>> len(party6.companies) == 0
+    True