Add translated descriptor for Selection field

issue3679
review10401002

CHANGELOG

@@ -1,3 +1,4 @@
+* Add translated descriptor for Selection field
 * Add tree_state attribute on tree view
 * Allow to sync XML data
 * Remove on_change calls in Model.default_get

doc/ref/models/fields.rst

@@ -413,6 +413,13 @@ A string field with limited values to choice.
     If true, the human-readable values will be translated. Default value is
     ``True``.
 
+Instance methods:
+
+.. method:: Selection.translated([name])
+
+    Returns a descriptor for the translated value of the field. The descriptor
+    must be used on the same class as the field.
+
 Reference
 ---------
 

doc/ref/models/models.rst

@@ -309,6 +309,8 @@ CLass methods:
     Return a list of list of values for each ``records``.
     The list of values follows ``fields_names``.
     Relational fields are defined with ``/`` at any depth.
+    Descriptor on fields are available by appending ``.`` and the name of the
+    method on the field that returns the descriptor.
 
 .. classmethod:: ModelStorage.import_data(fields_names, data)
 

trytond/model/fields/selection.py

@@ -63,3 +63,29 @@ class Selection(Field):
         for key, value in selections:
             whens.append((column == key, value))
         return [Case(*whens, else_=column)]
+
+    def translated(self, name=None):
+        "Return a descriptor for the translated value of the field"
+        if name is None:
+            name = self.name
+        if name is None:
+            raise ValueError('Missing name argument')
+        return TranslatedSelection(name)
+
+
+class TranslatedSelection(object):
+    'A descriptor for translated value of Selection field'
+
+    def __init__(self, name):
+        self.name = name
+
+    def __get__(self, inst, cls):
+        if inst is None:
+            return self
+        selection = dict(cls.fields_get([self.name])[self.name]['selection'])
+        value = getattr(inst, self.name)
+        # None and '' are equivalent
+        if value is None or value == '':
+            if value not in selection:
+                value = {None: '', '': None}[value]
+        return selection[value]

trytond/model/modelstorage.py

@@ -452,6 +452,9 @@ class ModelStorage(Model):
                 if not isinstance(value, ModelStorage):
                     break
                 field_name = fields_tree[i]
+                descriptor = None
+                if '.' in field_name:
+                    field_name, descriptor = field_name.split('.')
                 eModel = pool.get(value.__name__)
                 field = eModel._fields[field_name]
                 if field.states and 'invisible' in field.states:
@@ -467,7 +470,10 @@ class ModelStorage(Model):
                     if invisible:
                         value = ''
                         break
-                value = getattr(value, field_name)
+                if descriptor:
+                    value = getattr(field, descriptor)().__get__(value, eModel)
+                else:
+                    value = getattr(value, field_name)
                 if isinstance(value, (list, tuple)):
                     first = True
                     child_fields_names = [(x[:i + 1] == fields_tree[:i + 1] and

trytond/tests/test.py

@@ -604,6 +604,7 @@ class Selection(ModelSQL):
     select = fields.Selection([
             ('', ''), ('arabic', 'Arabic'), ('hexa', 'Hexadecimal')],
         'Selection')
+    select_string = select.translated('select')
     dyn_select = fields.Selection('get_selection',
         'Instance Dynamic Selection')
     dyn_select_static = fields.Selection('static_selection',

trytond/tests/test_exportdata.py

@@ -216,8 +216,9 @@ class ExportDataTestCase(unittest.TestCase):
                         'selection': 'select1',
                         }])
             self.assertEqual(
-                self.export_data.export_data([export1], ['selection']),
-                [['select1']])
+                self.export_data.export_data([export1], ['selection',
+                        'selection.translated']),
+                [['select1', 'Select 1']])
 
             export2, = self.export_data.create([{
                         'selection': None,

trytond/tests/test_fields.py

@@ -3060,10 +3060,12 @@ class FieldsTestCase(unittest.TestCase):
             selection1, = self.selection.create([{'select': 'arabic'}])
             self.assert_(selection1)
             self.assertEqual(selection1.select, 'arabic')
+            self.assertEqual(selection1.select_string, 'Arabic')
 
             selection2, = self.selection.create([{'select': None}])
             self.assert_(selection2)
             self.assertEqual(selection2.select, None)
+            self.assertEqual(selection2.select_string, '')
 
             self.assertRaises(UserError, self.selection.create,
                 [{'select': 'chinese'}])