ability to disable warnings validation

tiramisu/option/baseoption.py

@@ -581,9 +581,11 @@ class Option(OnlyOption):
             if warning:
                 msg = _("warning on the value of the option {0}: {1}").format(
                     self.impl_getname(), warning)
-                warnings.warn_explicit(ValueWarning(msg, self),
-                                       ValueWarning,
-                                       self.__class__.__name__, 0)
+                if context is None or 'warnings' in \
+                        context.cfgimpl_get_settings():
+                    warnings.warn_explicit(ValueWarning(msg, self),
+                                           ValueWarning,
+                                           self.__class__.__name__, 0)
             elif error:
                 raise ValueError(_("invalid value for option {0}: {1}").format(
                     self.impl_getname(), error))

tiramisu/setting.py

@@ -78,8 +78,11 @@ everything_frozen
 validator
     launch validator set by user in option (this property has no effect
     for internal validator)
+
+warnings
+    display warnings during validation
 """
-default_properties = ('cache', 'expire', 'validator')
+default_properties = ('cache', 'expire', 'validator', 'warnings')
 
 """Config can be in two defaut mode: