Match IntegerField validation with Django's, preventing decimal values being stored as ints, fixes #2835.

Match IntegerField validation with Django IntegerField, prevents decimal values being stored as ints, fixes #2835
 On branch master

Author: Ryan Allen

rest_framework/fields.py

@@ -682,7 +682,7 @@ def to_internal_value(self, data):
             self.fail('max_string_length')
 
         try:
-            data = int(data)
+            data = int(re.compile(r'\.0*\s*$').sub('', str(data)))
         except (ValueError, TypeError):
             self.fail('invalid')
         return data

tests/test_fields.py

@@ -549,10 +549,13 @@ class TestIntegerField(FieldValues):
         1: 1,
         0: 0,
         1.0: 1,
-        0.0: 0
+        0.0: 0,
+        '1.0': 1
     }
     invalid_inputs = {
-        'abc': ['A valid integer is required.']
+        0.5: ['A valid integer is required.'],
+        'abc': ['A valid integer is required.'],
+        '0.5': ['A valid integer is required.']
     }
     outputs = {
         '1': 1,