options: Add a permitted_kwargs function

I've typo'd "value" for the last time, options needs a kwargs validator.
This validator is slightly different than the one used by the main
parser, since it operates on a much simpler representation than the
other one does, and they are not interchangeable.

This also changes the optinterpreter to use pop on 'type' and
'description' so that they're not passed to the validator as kwargs.

mesonbuild/optinterpreter.py

@@ -12,10 +12,13 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import os, re
+import functools
+
 from . import mparser
 from . import coredata
 from . import mesonlib
-import os, re
+
 
 forbidden_option_names = coredata.get_builtin_options()
 forbidden_prefixes = {'c_',
@@ -43,15 +46,33 @@ def is_invalid_name(name):
 class OptionException(mesonlib.MesonException):
     pass
 
+
+def permitted_kwargs(permitted):
+    """Function that validates kwargs for options."""
+    def _wraps(func):
+        @functools.wraps(func)
+        def _inner(name, description, kwargs):
+            bad = [a for a in kwargs.keys() if a not in permitted]
+            if bad:
+                raise OptionException('Invalid kwargs for option "{}": "{}"'.format(
+                    name, ' '.join(bad)))
+            return func(name, description, kwargs)
+        return _inner
+    return _wraps
+
+
 optname_regex = re.compile('[^a-zA-Z0-9_-]')
 
+@permitted_kwargs({'value'})
 def StringParser(name, description, kwargs):
     return coredata.UserStringOption(name, description,
                                      kwargs.get('value', ''), kwargs.get('choices', []))
 
+@permitted_kwargs({'value'})
 def BooleanParser(name, description, kwargs):
     return coredata.UserBooleanOption(name, description, kwargs.get('value', True))
 
+@permitted_kwargs({'value', 'choices'})
 def ComboParser(name, description, kwargs):
     if 'choices' not in kwargs:
         raise OptionException('Combo option missing "choices" keyword.')
@@ -141,7 +162,7 @@ class OptionInterpreter:
         (posargs, kwargs) = self.reduce_arguments(node.args)
         if 'type' not in kwargs:
             raise OptionException('Option call missing mandatory "type" keyword argument')
-        opt_type = kwargs['type']
+        opt_type = kwargs.pop('type')
         if opt_type not in option_types:
             raise OptionException('Unknown type %s.' % opt_type)
         if len(posargs) != 1:
@@ -155,7 +176,7 @@ class OptionInterpreter:
             raise OptionException('Option name %s is reserved.' % opt_name)
         if self.subproject != '':
             opt_name = self.subproject + ':' + opt_name
-        opt = option_types[opt_type](opt_name, kwargs.get('description', ''), kwargs)
+        opt = option_types[opt_type](opt_name, kwargs.pop('description', ''), kwargs)
         if opt.description == '':
             opt.description = opt_name
         if opt_name in self.cmd_line_options:

test cases/failing/62 bad option argument/meson.build

@@ -0,0 +1,3 @@
+project('bad option')
+
+get_option('name')

test cases/failing/62 bad option argument/meson_options.txt

@@ -0,0 +1 @@
+option('name', type : 'string', vaule : 'foo')