Do not merge fields into _source

Fixes #1015

Author: honzakral

elasticsearch_dsl/utils.py

@@ -409,13 +409,6 @@ def __get_field(cls, name):
     def from_es(cls, hit):
         meta = hit.copy()
         data = meta.pop('_source', {})
-        if 'fields' in meta:
-            for k, v in iteritems(meta.pop('fields')):
-                if k.startswith('_') and k[1:] in META_FIELDS:
-                    meta[k] = v
-                else:
-                    data[k] = v
-
         doc = cls(meta=meta)
         doc._from_dict(data)
         return doc

test_elasticsearch_dsl/test_document.py

@@ -572,4 +572,6 @@ class Index:
 
     c = Company.from_es(doc)
 
-    assert c.to_dict() == {'city': 'Amsterdam', 'hello': 'world', 'name': 'Elasticsearch', "_tags": ["search"], "_tagline": "You know, for search"}
+    assert c.meta.fields._tags == ['search']
+    assert c.meta.fields._routing == 'es'
+    assert c._tagline == 'You know, for search'