Support for mutable and immutable configurations

tests/json/test_json.py

@@ -14,6 +14,7 @@
 
 from src.config_parser.json import JSONConfiguration
 from src.config_parser.exceptions import JSONObjectSyntaxError, JSONValueSyntaxError, JSONStringSyntaxError, JSONArraySyntaxError, EscapeSequenceSyntaxError
+from src.config_parser import set_mutability
 
 def test_json_configuration():
     # Test valid JSON configuration parsing
@@ -220,4 +221,26 @@ def test_json_configuration():
         JSONConfiguration.from_string('')
         assert False, 'Excepted JSONValueSyntaxError'
     except JSONValueSyntaxError:
+        pass
+
+def test_mutability():
+    config = JSONConfiguration(mutable=False)
+    try:
+        config.key = 'value'
+        assert False, 'Expected TypeError'
+    except TypeError:
+        pass
+
+    set_mutability(config, True)
+    assert config._mutable == True
+
+    config.key = 'value'
+
+    set_mutability(config, False)
+    assert config._mutable == False
+
+    try:
+        del config.key
+        assert False, 'Expected TypeError'
+    except TypeError:
         pass