Merge pull request #3 from wimglenn/develop

Support for anchors/references

oyaml.py

@@ -4,23 +4,27 @@
 import yaml as pyyaml
 
 
-_viewitems = 'viewitems' if sys.version_info < (3,) else 'items'
+_items = 'viewitems' if sys.version_info < (3,) else 'items'
 
 
-def _representer(dumper, data):
-    return dumper.represent_dict(getattr(data, _viewitems)())
+def map_representer(dumper, data):
+    return dumper.represent_dict(getattr(data, _items)())
 
 
-def _constructor(loader, node):
+def map_constructor(loader, node):
+    loader.flatten_mapping(node)
     return OrderedDict(loader.construct_pairs(node))
 
 
-pyyaml.add_representer(dict, _representer)
-pyyaml.add_representer(OrderedDict, _representer)
+pyyaml.add_representer(dict, map_representer)
+pyyaml.add_representer(OrderedDict, map_representer)
 
 
 if sys.version_info < (3, 7):
-    pyyaml.add_constructor(pyyaml.resolver.BaseResolver.DEFAULT_MAPPING_TAG, _constructor)
+    pyyaml.add_constructor('tag:yaml.org,2002:map', map_constructor)
+
+
+del map_constructor, map_representer
 
 
 # Merge PyYAML namespace into ours.

setup.py

@@ -2,7 +2,7 @@
 
 setup(
     name='oyaml',
-    version='0.1',
+    version='0.2',
     description='Ordered YAML: drop-in replacement for PyYAML which preserves dict ordering',
     author='Wim Glenn',
     author_email='hey@wimglenn.com',

test_oyaml.py

@@ -29,3 +29,38 @@ def test_loads_to_std_dict():
     loaded = yaml.load('{k1: v1, k3: v3, k2: v2}')
     assert not isinstance(loaded, OrderedDict)
     assert isinstance(loaded, dict)
+
+
+def test_anchors_and_references():
+    text = '''
+        defaults:
+          all: &all
+            product: foo
+          development: &development
+            <<: *all
+            profile: bar
+
+        development:
+          platform:
+            <<: *development
+            host: baz
+    '''
+    expected_load = {
+        'defaults': {
+            'all': {
+                'product': 'foo',
+            },
+            'development': {
+                'product': 'foo',
+                'profile': 'bar',
+            },
+        },
+        'development': {
+            'platform': {
+                'host': 'baz',
+                'product': 'foo',
+                'profile': 'bar',
+            },
+        },
+    }
+    assert yaml.load(text) == expected_load