Validation should return exception, not raises exception

Don't check force_store_value for SymLinkOption

test/test_freeze.py

@@ -7,7 +7,7 @@ from py.test import raises
 
 from tiramisu.setting import owners, groups
 from tiramisu.option import ChoiceOption, BoolOption, IntOption, FloatOption, \
-    StrOption, OptionDescription
+    StrOption, OptionDescription, SymLinkOption
 from tiramisu.config import Config
 from tiramisu.error import PropertiesOptionError, ConfigError
 
@@ -28,13 +28,14 @@ def make_description_freeze():
                                 requires=({'option': booloption, 'expected': True, 'action': 'hidden'},))
     wantref2_option = BoolOption('wantref2', 'Test requires', default=False, properties=('force_store_value', 'hidden'))
     wantref3_option = BoolOption('wantref3', 'Test requires', default=[False], multi=True, properties=('force_store_value',))
+    st2 = SymLinkOption('st2', wantref3_option)
     wantframework_option = BoolOption('wantframework', 'Test requires',
                                       default=False,
                                       requires=({'option': booloption, 'expected': True, 'action': 'hidden'},))
 
     gcgroup = OptionDescription('gc', '', [gcoption, gcdummy, floatoption])
     descr = OptionDescription('tiramisu', '', [gcgroup, booloption, objspaceoption,
-                              wantref_option, wantref2_option, wantref3_option, stroption,
+                              wantref_option, wantref2_option, wantref3_option, st2, stroption,
                               wantframework_option,
                               intoption, boolop])
     return descr