_yaml: Add 'as_bool()' and 'is_none()' to ScalarNode

- 'as_bool()' casts a ScalarNode into a boolean, understanding both
  'True' and 'False' as truthy-falsy values, as per node_get(type=bool)
  behavior
- 'is_none()' allwos checking whether the scalar node contains a 'None'
  value. Since 'None' cannot be used when working with booleans, we need
  to have a way of checking for 'None' when we actually need the
  information of whether the value is unset.
- Adapt all call places to use the new API

1 files changed, 1 insertions, 1 deletions

diff --git a/src/buildstream/plugins/sources/remote.py b/src/buildstream/plugins/sources/remote.py
index 4e9fe4f7d..bb4c11325 100644
--- a/src/buildstream/plugins/sources/remote.py
+++ b/src/buildstream/plugins/sources/remote.py
@@ -63,7 +63,7 @@ class RemoteSource(DownloadableFileSource):
         super().configure(node)
 
         self.filename = node.get_str('filename', os.path.basename(self.url))
-        self.executable = self.node_get_member(node, bool, 'executable', False)
+        self.executable = node.get_bool('executable', default=False)
 
         if os.sep in self.filename:
             raise SourceError('{}: filename parameter cannot contain directories'.format(self),