Ruamel yaml

confuse/core.py

@@ -19,7 +19,7 @@
 
 import errno
 import os
-import yaml
+import ruamel.yaml as yaml
 from collections import OrderedDict
 
 from . import util
@@ -527,7 +527,10 @@ def _add_user_source(self):
         exists.
         """
         filename = self.user_config_path()
-        self.add(YamlSource(filename, loader=self.loader, optional=True))
+        source = YamlSource(filename, loader=self.loader, optional=True)
+        # Save value to keep comments
+        self.value = source.load()
+        self.add(source)
 
     def _add_default_source(self):
         """Add the package's default configuration settings. This looks
@@ -537,8 +540,11 @@ def _add_default_source(self):
         if self.modname:
             if self._package_path:
                 filename = os.path.join(self._package_path, DEFAULT_FILENAME)
-                self.add(YamlSource(filename, loader=self.loader,
-                                    optional=True, default=True))
+                source = YamlSource(filename, loader=self.loader,
+                                    optional=True, default=True)
+                # Save value to keep comments
+                self.value = source.load()
+                self.add(source)
 
     def read(self, user=True, defaults=True):
         """Find and read the files for this configuration and set them
@@ -647,24 +653,13 @@ def dump(self, full=True, redact=False):
             temp_root.redactions = self.redactions
             out_dict = temp_root.flatten(redact=redact)
 
-        yaml_out = yaml.dump(out_dict, Dumper=yaml_util.Dumper,
+        # Update configuration value 
+        self.value.update(out_dict)
+
+        return yaml.dump(self.value, Dumper=yaml_util.Dumper,
                              default_flow_style=None, indent=4,
                              width=1000)
-
-        # Restore comments to the YAML text.
-        default_source = None
-        for source in self.sources:
-            if source.default:
-                default_source = source
-                break
-        if default_source and default_source.filename:
-            with open(default_source.filename, 'rb') as fp:
-                default_data = fp.read()
-            yaml_out = yaml_util.restore_yaml_comments(
-                yaml_out, default_data.decode('utf-8'))
-
-        return yaml_out
-
+
     def reload(self):
         """Reload all sources from the file system.
 

confuse/exceptions.py

@@ -1,6 +1,6 @@
 from __future__ import division, absolute_import, print_function
 
-import yaml
+import ruamel.yaml as yaml
 
 __all__ = [
     'ConfigError', 'NotFoundError', 'ConfigValueError', 'ConfigTypeError',

confuse/sources.py

@@ -73,7 +73,6 @@ def __init__(self, filename=None, default=False, base_for_paths=False,
         super(YamlSource, self).__init__({}, filename, default, base_for_paths)
         self.loader = loader
         self.optional = optional
-        self.load()
 
     def load(self):
         """Load YAML data from the source's filename.
@@ -84,6 +83,8 @@ def load(self):
             value = yaml_util.load_yaml(self.filename,
                                         loader=self.loader) or {}
         self.update(value)
+        # Return value for round tripping
+        return value
 
 
 class EnvSource(ConfigSource):

confuse/yaml_util.py

@@ -1,14 +1,14 @@
 from __future__ import division, absolute_import, print_function
 
 from collections import OrderedDict
-import yaml
+import ruamel.yaml as yaml
 from .exceptions import ConfigReadError
 from .util import BASESTRING
 
 # YAML loading.
 
 
-class Loader(yaml.SafeLoader):
+class Loader(yaml.RoundTripLoader):
     """A customized YAML loader. This loader deviates from the official
     YAML spec in a few convenient ways:
 
@@ -28,30 +28,30 @@ def construct_yaml_map(self, node):
         value = self.construct_mapping(node)
         data.update(value)
 
-    def construct_mapping(self, node, deep=False):
-        if isinstance(node, yaml.MappingNode):
-            self.flatten_mapping(node)
-        else:
-            raise yaml.constructor.ConstructorError(
-                None, None,
-                u'expected a mapping node, but found %s' % node.id,
-                node.start_mark
-            )
-
-        mapping = OrderedDict()
-        for key_node, value_node in node.value:
-            key = self.construct_object(key_node, deep=deep)
-            try:
-                hash(key)
-            except TypeError as exc:
-                raise yaml.constructor.ConstructorError(
-                    u'while constructing a mapping',
-                    node.start_mark, 'found unacceptable key (%s)' % exc,
-                    key_node.start_mark
-                )
-            value = self.construct_object(value_node, deep=deep)
-            mapping[key] = value
-        return mapping
+    # def construct_mapping(self, node, deep=False):
+    #     if isinstance(node, yaml.MappingNode):
+    #         self.flatten_mapping(node)
+    #     else:
+    #         raise yaml.constructor.ConstructorError(
+    #             None, None,
+    #             u'expected a mapping node, but found %s' % node.id,
+    #             node.start_mark
+    #         )
+
+    #     mapping = OrderedDict()
+    #     for key_node, value_node in node.value:
+    #         key = self.construct_object(key_node, deep=deep)
+    #         try:
+    #             hash(key)
+    #         except TypeError as exc:
+    #             raise yaml.constructor.ConstructorError(
+    #                 u'while constructing a mapping',
+    #                 node.start_mark, 'found unacceptable key (%s)' % exc,
+    #                 key_node.start_mark
+    #             )
+    #         value = self.construct_object(value_node, deep=deep)
+    #         mapping[key] = value
+    #     return mapping
 
     # Allow bare strings to begin with %. Directives are still detected.
     def check_plain(self):
@@ -64,12 +64,13 @@ def add_constructors(loader):
         and maps. Call this method on a custom Loader class to make it behave
         like Confuse's own Loader
         """
-        loader.add_constructor('tag:yaml.org,2002:str',
-                               Loader._construct_unicode)
-        loader.add_constructor('tag:yaml.org,2002:map',
-                               Loader.construct_yaml_map)
-        loader.add_constructor('tag:yaml.org,2002:omap',
-                               Loader.construct_yaml_map)
+        # Disable this for now
+        # loader.add_constructor('tag:yaml.org,2002:str',
+        #                        Loader._construct_unicode)
+        # loader.add_constructor('tag:yaml.org,2002:map',
+        #                        Loader.construct_yaml_map)
+        # loader.add_constructor('tag:yaml.org,2002:omap',
+        #                        Loader.construct_yaml_map)
 
 
 Loader.add_constructors(Loader)
@@ -133,35 +134,35 @@ def parse_as_scalar(value, loader=Loader):
 
 # YAML dumping.
 
-class Dumper(yaml.SafeDumper):
+class Dumper(yaml.RoundTripDumper):
     """A PyYAML Dumper that represents OrderedDicts as ordinary mappings
     (in order, of course).
     """
     # From http://pyyaml.org/attachment/ticket/161/use_ordered_dict.py
-    def represent_mapping(self, tag, mapping, flow_style=None):
-        value = []
-        node = yaml.MappingNode(tag, value, flow_style=flow_style)
-        if self.alias_key is not None:
-            self.represented_objects[self.alias_key] = node
-        best_style = False
-        if hasattr(mapping, 'items'):
-            mapping = list(mapping.items())
-        for item_key, item_value in mapping:
-            node_key = self.represent_data(item_key)
-            node_value = self.represent_data(item_value)
-            if not (isinstance(node_key, yaml.ScalarNode)
-                    and not node_key.style):
-                best_style = False
-            if not (isinstance(node_value, yaml.ScalarNode)
-                    and not node_value.style):
-                best_style = False
-            value.append((node_key, node_value))
-        if flow_style is None:
-            if self.default_flow_style is not None:
-                node.flow_style = self.default_flow_style
-            else:
-                node.flow_style = best_style
-        return node
+    # def represent_mapping(self, tag, mapping, flow_style=None):
+    #     value = []
+    #     node = yaml.MappingNode(tag, value, flow_style=flow_style)
+    #     if self.alias_key is not None:
+    #         self.represented_objects[self.alias_key] = node
+    #     best_style = False
+    #     if hasattr(mapping, 'items'):
+    #         mapping = list(mapping.items())
+    #     for item_key, item_value in mapping:
+    #         node_key = self.represent_data(item_key)
+    #         node_value = self.represent_data(item_value)
+    #         if not (isinstance(node_key, yaml.ScalarNode)
+    #                 and not node_key.style):
+    #             best_style = False
+    #         if not (isinstance(node_value, yaml.ScalarNode)
+    #                 and not node_value.style):
+    #             best_style = False
+    #         value.append((node_key, node_value))
+    #     if flow_style is None:
+    #         if self.default_flow_style is not None:
+    #             node.flow_style = self.default_flow_style
+    #         else:
+    #             node.flow_style = best_style
+    #     return node
 
     def represent_list(self, data):
         """If a list has less than 4 items, represent it in inline style
@@ -190,39 +191,8 @@ def represent_none(self, data):
         return self.represent_scalar('tag:yaml.org,2002:null', '')
 
 
-Dumper.add_representer(OrderedDict, Dumper.represent_dict)
+# This code doesn't work yet  with round tripping
+# Dumper.add_representer(OrderedDict, Dumper.represent_dict)
 Dumper.add_representer(bool, Dumper.represent_bool)
 Dumper.add_representer(type(None), Dumper.represent_none)
 Dumper.add_representer(list, Dumper.represent_list)
-
-
-def restore_yaml_comments(data, default_data):
-    """Scan default_data for comments (we include empty lines in our
-    definition of comments) and place them before the same keys in data.
-    Only works with comments that are on one or more own lines, i.e.
-    not next to a yaml mapping.
-    """
-    comment_map = dict()
-    default_lines = iter(default_data.splitlines())
-    for line in default_lines:
-        if not line:
-            comment = "\n"
-        elif line.startswith("#"):
-            comment = "{0}\n".format(line)
-        else:
-            continue
-        while True:
-            line = next(default_lines)
-            if line and not line.startswith("#"):
-                break
-            comment += "{0}\n".format(line)
-        key = line.split(':')[0].strip()
-        comment_map[key] = comment
-    out_lines = iter(data.splitlines())
-    out_data = ""
-    for line in out_lines:
-        key = line.split(':')[0].strip()
-        if key in comment_map:
-            out_data += comment_map[key]
-        out_data += "{0}\n".format(line)
-    return out_data

pyproject.toml

@@ -8,7 +8,7 @@ author = "Adrian Sampson"
 author-email = "[email protected]"
 home-page = "https://github.com/beetbox/confuse"
 requires = [
-    "pyyaml"
+    "ruamel.yaml"
 ]
 description-file = "README.rst"
 requires-python = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, <4"

requirements.txt

@@ -1 +1 @@
-PyYAML
+ruamel.yaml

test/test_yaml.py

@@ -1,7 +1,7 @@
 from __future__ import division, absolute_import, print_function
 
 import confuse
-import yaml
+import ruamel.yaml as yaml
 import unittest
 from . import TempDir
 

tox.ini

@@ -15,7 +15,7 @@ deps =
     coverage
     nose
     nose-show-skipped
-    pyyaml
+    ruamel.yaml
     pathlib