1 files changed, 69 insertions, 0 deletions
diff --git a/waftools/features.py b/waftools/features.py
new file mode 100644
index 0000000000..1385d41dbf
--- /dev/null
+++ b/waftools/features.py
@@ -0,0 +1,69 @@
+from waflib.Options import OptionsContext
+
+class Feature(object):
+    def __init__(self, group, feature):
+        self.group     = group
+        self.identifier, self.attributes = feature['name'], feature
+
+    def add_options(self):
+        [self.add_option(option_rule) for option_rule in self.option_rules()]
+
+    def add_option(self, rule):
+        self.group.add_option(self.option(rule['state']),
+                              action=rule['action'],
+                              default=rule['default'],
+                              dest=self.storage(),
+                              help=self.help(rule['state']))
+
+    # private
+    def option_rules(self):
+        return {
+            'autodetect': [
+                {'state': 'disable', 'action': 'store_false', 'default': None},
+                {'state': 'enable',  'action': 'store_true',  'default': None},
+            ],
+            'disable': [
+                {'state': 'disable', 'action': 'store_false', 'default': False},
+                {'state': 'enable',  'action': 'store_true',  'default': False},
+            ],
+            'enable': [
+                {'state': 'disable', 'action': 'store_false', 'default': True},
+            ],
+        }[self.behaviour()]
+
+
+    def behaviour(self):
+        if 'default' in self.attributes:
+            return self.attributes['default']
+        else:
+            return 'autodetect'
+
+
+    def option(self, state):
+        return "--{0}-{1}".format(state, self.identifier)
+
+    def help(self, state):
+        return "{0} {1} [{2}]" \
+            .format(state, self.attributes['desc'], self.behaviour())
+
+    def storage(self):
+        return "enable_{0}".format(self.identifier)
+
+def add_feature(group, feature):
+    Feature(group, feature).add_options()
+
+def parse_features(opt, group_name, features):
+    def is_feature(dep):
+        return dep['name'].find('--') >= 0
+
+    def strip_feature(dep):
+        dep['name'] = dep['name'].lstrip('-')
+        return dep
+
+    features = [strip_feature(dep) for dep in features if is_feature(dep)]
+    group = opt.get_option_group(group_name)
+    if not group:
+        group = opt.add_option_group(group_name)
+    [add_feature(group, feature) for feature in features]
+
+OptionsContext.parse_features = parse_features