misc: fix behaviour on missing variables with a known prefix (#26269)

tests/test_formdata.py

@@ -571,6 +571,7 @@ def variable_test_data(pub):
         fields.DateField(id='3', label='date', varname='datefield'),
         fields.ItemsField(id='4', label='items', items=['aa', 'ab', 'ac'], varname='itemsfield'),
         fields.FileField(id='5', label='file', varname='filefield'),
+        fields.StringField(id='6', label='string2', varname='foo_foo_baz_baz'),
     ]
     formdef.workflow_roles = {'_receiver': role.id}
     formdef.geolocations = {'base': 'Base'}
@@ -587,6 +588,7 @@ def variable_test_data(pub):
         '4': ['aa', 'ac'],
         '4_display': 'aa, ac',
         '5': PicklableUpload('test.txt', 'text/plain'),
+        '6': 'other',
     }
     formdata.data['5'].receive(['hello world'])
     formdata.geolocations = {'base': {'lat': 1, 'lon': 2}}
@@ -645,6 +647,24 @@ def test_lazy_variables(pub, variable_test_data):
         assert context['form_var_foo_foo'] + 'ab' == 'barab'
         for item in enumerate(context['form_var_foo_foo']):
             assert item in [(0, 'b'), (1, 'a'), (2, 'r')]
+        assert context['form_var_foo_foo_baz_baz'] == 'other'
+
+def test_lazy_variables_missing(pub, variable_test_data):
+    formdef =  FormDef.select()[0]
+    formdata = formdef.data_class()()
+    formdata.just_created()
+    formdata.data = {
+        '0': 'bar',
+    }
+    pub.substitutions.reset()
+    pub.substitutions.feed(formdef)
+    pub.substitutions.feed(formdata)
+    for mode in (None, 'lazy'):
+        context = pub.substitutions.get_context_variables(mode=mode)
+        assert context['form_var_foo_foo_baz_baz'] is None
+        assert context['form_var_foo_foo'] == 'bar'
+        with pytest.raises(KeyError):
+            assert context['form_var_foo_foo_xxx'] == 'bar'
 
 def test_lazy_conditions(pub, variable_test_data):
     condition = Condition({'type': 'django', 'value': 'form_var_foo_foo == "bar"'})
@@ -671,6 +691,10 @@ def test_lazy_conditions(pub, variable_test_data):
     condition = Condition({'type': 'django', 'value': 'form_user_backoffice_access'})
     assert condition.evaluate() is False
 
+    condition = Condition({'type': 'python', 'value':
+        'vars().get("form_var_foo_foo_xxx", "") == ""'})
+    assert condition.evaluate() is True
+
     user = pub.user_class.select()[0]
     user.is_admin = True
     user.store()

wcs/qommon/substitution.py

@@ -150,7 +150,8 @@ class CompatibilityNamesDict(dict):
                             current_dict = current_dict[part]
                         else:
                             current_dict = getattr(current_dict, part)
-                    except (AttributeError, KeyError):
+                    except (AttributeError, KeyError, TypeError):
+                        # TypeError will happen if indexing is used on a string
                         if i == 1:
                             raise KeyError(key)
                     else: