[IMP] sale_timesheet: convert onchanges to stored-editable computed fields.

As now the partner_id field is fully computed and not modified by an onchange method anymore, some tests have been updated.

addons/sale_timesheet/models/project.py

@@ -263,11 +263,12 @@ class ProjectTask(models.Model):
 
     def write(self, values):
         old_sale_line_id = dict([(t.id, t.sale_line_id.id) for t in self])
+        res = super(ProjectTask, self).write(values)
+        # Done after super to avoid constraints on field recomputation
         if values.get('project_id'):
             project_dest = self.env['project.project'].browse(values['project_id'])
             if project_dest.billable_type == 'employee_rate':
-                values['sale_line_id'] = False
-        res = super(ProjectTask, self).write(values)
+                self.write({'sale_line_id': False})
         if 'sale_line_id' in values and self.filtered('allow_timesheets').sudo().timesheet_ids:
             so = self.env['sale.order.line'].browse(values['sale_line_id']).order_id
             if so and not so.analytic_account_id:

addons/sale_timesheet/tests/test_project_billing.py

@@ -340,7 +340,10 @@ class TestProjectBilling(TestCommonSaleTimesheetNoChart):
         self.assertEqual(timesheet4.so_line, self.so1_line_deliver_no_task, "The timesheet should be linked to SOL on the project, as no entry for TDE in project map and no SOL on task")
 
     def test_billing_task_rate(self):
-        """ Check task and subtask creation, and timesheeting in a project billed at 'task rate'. Then move the task into a 'employee rate' project then, 'non billable'. """
+        """
+        Check task and subtask creation, and timesheeting in a project billed at 'task rate'.
+        Then move the task into a 'employee rate' project then, 'non billable'.
+        """
         Task = self.env['project.task'].with_context(tracking_disable=True)
         Timesheet = self.env['account.analytic.line']
 
@@ -350,7 +353,6 @@ class TestProjectBilling(TestCommonSaleTimesheetNoChart):
         # create a task
         task = Task.with_context(default_project_id=self.project_task_rate.id).create({
             'name': 'first task',
-            'partner_id': self.partner_customer_usd.id,
         })
         task._onchange_project()