_yaml: Introduce 'MappingNode.values()'

This is to mimic the 'dict.values()' interface.

- Adapt parts of the code calling 'node_items' but ignoring the
first value to use this instead

1 files changed, 7 insertions, 5 deletions

diff --git a/src/buildstream/_options/optionpool.py b/src/buildstream/_options/optionpool.py
index 23459d3c5..af0f99b97 100644
--- a/src/buildstream/_options/optionpool.py
+++ b/src/buildstream/_options/optionpool.py
@@ -185,10 +185,11 @@ class OptionPool():
         # Now recurse into nested dictionaries and lists
         # and process any indirectly nested conditionals.
         #
-        for _, value in _yaml.node_items(node):
-            if _yaml.is_node(value):
+        for value in node.values():
+            value_type = type(value)
+            if value_type is _yaml.MappingNode:
                 self.process_node(value)
-            elif isinstance(value, list):
+            elif value_type is _yaml.SequenceNode:
                 self._process_list(value)
 
     #######################################################
@@ -237,9 +238,10 @@ class OptionPool():
     #
     def _process_list(self, values):
         for value in values:
-            if _yaml.is_node(value):
+            value_type = type(value)
+            if value_type is _yaml.MappingNode:
                 self.process_node(value)
-            elif isinstance(value, list):
+            elif value_type is _yaml.SequenceNode:
                 self._process_list(value)
 
     # Process a single conditional, resulting in composition