Add option to have OrderedDict hooked on load(s)

src/hcl/api.py

@@ -42,30 +42,33 @@ def isHcl(s):
     raise ValueError("No HCL object could be decoded")
 
 
-def load(fp):
+def load(fp, object_pairs_hook=None):
     '''
         Deserializes a file-pointer like object into a python dictionary.
         The contents of the file must either be JSON or HCL.
 
         :param fp: An object that has a read() function
-
+        :param object_pairs_hook: is an optional function that behaves just like the json.load parameter does but only supports OrderedDict
         :returns: Dictionary
     '''
-    return loads(fp.read())
+    return loads(fp.read(), object_pairs_hook=object_pairs_hook)
 
 
-def loads(s):
+def loads(s, object_pairs_hook=None):
     '''
         Deserializes a string and converts it to a dictionary. The contents
         of the string must either be JSON or HCL.
-
+
+        :param object_pairs_hook: is an optional function that behaves just like the json.load parameter does but only supports OrderedDict
+
         :returns: Dictionary 
     '''
     s = u(s)
     if isHcl(s):
-        return HclParser().parse(s)
+        hcl_out = HclParser(object_pairs_hook=object_pairs_hook)
+        return hcl_out.parse(s)
     else:
-        return json.loads(s)
+        return json.loads(s, object_pairs_hook=object_pairs_hook)
 
 
 def dumps(*args, **kwargs):

src/hcl/parser.py

@@ -3,6 +3,7 @@
 
 from .lexer import Lexer
 from ply import lex, yacc
+from collections import OrderedDict
 
 import inspect
 
@@ -74,7 +75,11 @@ def objectlist_flat(self, lt, replace):
 
             from object.go: there's a flattened list structure
         '''
-        d = {}
+
+        if self.object_pairs_hook == OrderedDict:
+            d = OrderedDict()
+        else:
+            d = {}
 
         for k, v in lt:
             if k in d.keys() and not replace:
@@ -317,10 +322,11 @@ def p_error(self, p):
 
         raise ValueError(msg)
 
-    def __init__(self):
+    def __init__(self, object_pairs_hook=None):
         self.yacc = yacc.yacc(
             module=self, debug=False, optimize=1, picklefile=pickle_file
         )
+        self.object_pairs_hook = object_pairs_hook
 
     def parse(self, s):
         return self.yacc.parse(s, lexer=Lexer())

tests/test_parser.py

@@ -7,6 +7,7 @@
 from os.path import join, dirname
 import hcl
 import json
+from collections import OrderedDict
 
 import pytest
 
@@ -64,28 +65,43 @@
 
 @pytest.mark.parametrize("hcl_fname,invalid", PARSE_FIXTURES)
 def test_parser_bytes(hcl_fname, invalid):
-    
+
     with open(join(PARSE_FIXTURE_DIR, hcl_fname), 'rb') as fp:
-        
+
         input = fp.read()
         print(input)
-        
+
         if not invalid:
             hcl.loads(input)
         else:
             with pytest.raises(ValueError):
                 hcl.loads(input)
-                
+
 @pytest.mark.parametrize("hcl_fname,invalid", PARSE_FIXTURES)
 def test_parser_str(hcl_fname, invalid):
-    
+
     with open(join(PARSE_FIXTURE_DIR, hcl_fname), 'r') as fp:
-        
+
         input = fp.read()
         print(input)
-        
+
         if not invalid:
             hcl.loads(input)
         else:
             with pytest.raises(ValueError):
                 hcl.loads(input)
+
+@pytest.mark.parametrize("hcl_fname,invalid", PARSE_FIXTURES)
+def test_parser_object_pairs_hook(hcl_fname, invalid):
+    with open(join(PARSE_FIXTURE_DIR, hcl_fname), 'r') as fp:
+
+        input = fp.read()
+        print(input)
+
+        if not invalid:
+            output = hcl.loads(input, object_pairs_hook=OrderedDict)
+            dummy = OrderedDict([])
+            assert type(output) == type(dummy)
+        else:
+            with pytest.raises(ValueError):
+                hcl.loads(input)