Add header grouping on report

issue6760
review351221002

asset.py

@@ -19,6 +19,8 @@ from trytond.wizard import (Wizard, StateView, StateTransition, StateReport,
 from trytond.tools import grouped_slice
 from trytond.modules.company import CompanyReport
 
+from .exceptions import PrintDepreciationTableError
+
 
 def date2datetime(date):
     return datetime.datetime.combine(date, datetime.time())
@@ -928,8 +930,8 @@ class AssetDepreciationTable(CompanyReport):
     __name__ = 'account.asset.depreciation_table'
 
     @classmethod
-    def get_context(cls, records, data):
-        context = super(AssetDepreciationTable, cls).get_context(records, data)
+    def get_context(cls, records, header, data):
+        context = super().get_context(records, header, data)
 
         AssetDepreciation = cls.get_asset_depreciation()
         AssetDepreciation.start_date = data['start_date']
@@ -1120,6 +1122,9 @@ class PrintDepreciationTable(Wizard):
                 ('end_date', '>', self.start.start_date),
                 ('state', '!=', 'draft'),
                 ])
+        if not assets:
+            raise PrintDepreciationTableError(
+                gettext('account_asset.msg_no_assets'))
         return action, {
             'ids': [a.id for a in assets],
             'start_date': self.start.start_date,

exceptions.py

@@ -0,0 +1,8 @@
+# This file is part of Tryton.  The COPYRIGHT file at the top level of
+# this repository contains the full copyright notices and license terms.
+
+from trytond.exceptions import UserError
+
+
+class PrintDepreciationTableError(UserError):
+    pass

message.xml

@@ -18,5 +18,8 @@ this repository contains the full copyright notices and license terms. -->
         <record model="ir.message" id="msg_invoice_line_asset_unique">
             <field name="text">Asset can be used only once on invoice line.</field>
         </record>
+        <record model="ir.message" id="msg_no_assets">
+            <field name="text">There is no started asset.</field>
+        </record>
     </data>
 </tryton>