resolves issue #274 replace dict with collections.OrderedDict when loading0.15.85

https://bitbucket.org/ruamel/yaml/issues/274/add-a-typ-ordered-for-a-middle-ground#comment-49783394

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6 files changed, 28 insertions, 9 deletions

diff --git a/CHANGES b/CHANGES
index bb6f0ae..bb25af7 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,11 @@
+[0, 15, 85]: 2019-01-08
+  - the types used by `SafeConstructor` for mappings and sequences can
+    now by set by assigning to `XXXConstructor.yaml_base_dict_type`
+    (and `..._list_type`), preventing the need to copy two methods
+    with 50+ lines that had `var = {}` hardcoded.  (Implemented to
+    help solve an feature request by `Anthony Sottile
+    <https://bitbucket.org/asottile/>`__ in an easier way)
+
 [0, 15, 84]: 2019-01-07
   - fix for `CommentedMap.copy()` not returning `CommentedMap`, let alone copying comments etc.
     (reported by `Anthony Sottile <https://bitbucket.org/asottile/>`__)
diff --git a/README.rst b/README.rst
index f42a5bd..7f929bb 100644
--- a/README.rst
+++ b/README.rst
@@ -4,8 +4,8 @@ ruamel.yaml
 
 ``ruamel.yaml`` is a YAML 1.2 loader/dumper package for Python.
 
-:version:       0.15.84
-:updated:       2019-01-07
+:version:       0.15.85
+:updated:       2019-01-08
 :documentation: http://yaml.readthedocs.io
 :repository:    https://bitbucket.org/ruamel/
 :pypi:          https://pypi.org/project/ruamel.yaml/
@@ -54,6 +54,14 @@ ChangeLog
 
 .. should insert NEXT: at the beginning of line for next key (with empty line)
 
+0.15.85 (2019-01-08):
+  - the types used by `SafeConstructor` for mappings and sequences can
+    now by set by assigning to `XXXConstructor.yaml_base_dict_type`
+    (and `..._list_type`), preventing the need to copy two methods
+    with 50+ lines that had `var = {}` hardcoded.  (Implemented to
+    help solve an feature request by `Anthony Sottile
+    <https://bitbucket.org/asottile/>`__ in an easier way)
+
 0.15.84 (2019-01-07):
   - fix for `CommentedMap.copy()` not returning `CommentedMap`, let alone copying comments etc.
     (reported by `Anthony Sottile <https://bitbucket.org/asottile/>`__)
diff --git a/__init__.py b/__init__.py
index 5719064..8a0ef9e 100644
--- a/__init__.py
+++ b/__init__.py
@@ -7,8 +7,8 @@ if False:  # MYPY
 
 _package_data = dict(
     full_package_name='ruamel.yaml',
-    version_info=(0, 15, 84),
-    __version__='0.15.84',
+    version_info=(0, 15, 85),
+    __version__='0.15.85',
     author='Anthon van der Neut',
     author_email='a.van.der.neut@ruamel.eu',
     description='ruamel.yaml is a YAML parser/emitter that supports roundtrip preservation of comments, seq/map flow style, and map key order',  # NOQA
diff --git a/_doc/_static/pypi.svg b/_doc/_static/pypi.svg
index f62388f..4c05b38 100644
--- a/_doc/_static/pypi.svg
+++ b/_doc/_static/pypi.svg
@@ -1 +1 @@
-<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="86" height="20"><linearGradient id="b" x2="0" y2="100%"><stop offset="0" stop-color="#bbb" stop-opacity=".1"/><stop offset="1" stop-opacity=".1"/></linearGradient><clipPath id="a"><rect width="86" height="20" rx="3" fill="#fff"/></clipPath><g clip-path="url(#a)"><path fill="#555" d="M0 0h33v20H0z"/><path fill="#007ec6" d="M33 0h53v20H33z"/><path fill="url(#b)" d="M0 0h86v20H0z"/></g><g fill="#fff" text-anchor="middle" font-family="DejaVu Sans,Verdana,Geneva,sans-serif" font-size="110"> <text x="175" y="150" fill="#010101" fill-opacity=".3" transform="scale(.1)" textLength="230">pypi</text><text x="175" y="140" transform="scale(.1)" textLength="230">pypi</text><text x="585" y="150" fill="#010101" fill-opacity=".3" transform="scale(.1)" textLength="430">0.15.84</text><text x="585" y="140" transform="scale(.1)" textLength="430">0.15.84</text></g> </svg>
+<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="86" height="20"><linearGradient id="b" x2="0" y2="100%"><stop offset="0" stop-color="#bbb" stop-opacity=".1"/><stop offset="1" stop-opacity=".1"/></linearGradient><clipPath id="a"><rect width="86" height="20" rx="3" fill="#fff"/></clipPath><g clip-path="url(#a)"><path fill="#555" d="M0 0h33v20H0z"/><path fill="#007ec6" d="M33 0h53v20H33z"/><path fill="url(#b)" d="M0 0h86v20H0z"/></g><g fill="#fff" text-anchor="middle" font-family="DejaVu Sans,Verdana,Geneva,sans-serif" font-size="110"> <text x="175" y="150" fill="#010101" fill-opacity=".3" transform="scale(.1)" textLength="230">pypi</text><text x="175" y="140" transform="scale(.1)" textLength="230">pypi</text><text x="585" y="150" fill="#010101" fill-opacity=".3" transform="scale(.1)" textLength="430">0.15.85</text><text x="585" y="140" transform="scale(.1)" textLength="430">0.15.85</text></g> </svg>
diff --git a/_test/test_api_change.py b/_test/test_api_change.py
index 9bb26b5..3f3d411 100644
--- a/_test/test_api_change.py
+++ b/_test/test_api_change.py
@@ -146,6 +146,7 @@ class TestRead:
         with pytest.raises(ConstructorError):
             yaml.load(s)
         # should parse fine
+        yaml = YAML(typ='safe')
         for _ in yaml.parse(s):
             pass
 
diff --git a/constructor.py b/constructor.py
index 65d6829..53e0d27 100644
--- a/constructor.py
+++ b/constructor.py
@@ -63,6 +63,8 @@ class BaseConstructor(object):
         if self.loader is not None and getattr(self.loader, '_constructor', None) is None:
             self.loader._constructor = self
         self.loader = loader
+        self.yaml_base_dict_type = dict
+        self.yaml_base_list_type = list
         self.constructed_objects = {}  # type: Dict[Any, Any]
         self.recursive_objects = {}  # type: Dict[Any, Any]
         self.state_generators = []  # type: List[Any]
@@ -207,13 +209,13 @@ class BaseConstructor(object):
             raise ConstructorError(
                 None, None, 'expected a mapping node, but found %s' % node.id, node.start_mark
             )
-        total_mapping = {}
+        total_mapping = self.yaml_base_dict_type()
         if getattr(node, 'merge', None) is not None:
             todo = [(node.merge, False), (node.value, False)]
         else:
             todo = [(node.value, True)]
         for values, check in todo:
-            mapping = {}  # type: Dict[Any, Any]
+            mapping = self.yaml_base_dict_type()  # type: Dict[Any, Any]
             for key_node, value_node in values:
                 # keys can be list -> deep
                 key = self.construct_object(key_node, deep=True)
@@ -686,13 +688,13 @@ class SafeConstructor(BaseConstructor):
 
     def construct_yaml_seq(self, node):
         # type: (Any) -> Any
-        data = []  # type: List[Any]
+        data = self.yaml_base_list_type()  # type: List[Any]
         yield data
         data.extend(self.construct_sequence(node))
 
     def construct_yaml_map(self, node):
         # type: (Any) -> Any
-        data = {}  # type: Dict[Any, Any]
+        data = self.yaml_base_dict_type()  # type: Dict[Any, Any]
         yield data
         value = self.construct_mapping(node)
         data.update(value)