diff --git a/tests/fields/test_edge_data_field.py b/tests/fields/test_edge_data_field.py
index 7fe6174..6863203 100644
--- a/tests/fields/test_edge_data_field.py
+++ b/tests/fields/test_edge_data_field.py
@@ -20,4 +20,4 @@ def test_parse(field, text, value, exc):
         with pytest.raises(exc):
             field.parse(text)
     else:
-        assert field.parse(text) == value
+        field.parse(text) == value
diff --git a/tests/models/test_problem.py b/tests/models/test_problem.py
index 86c254a..bd3640c 100644
--- a/tests/models/test_problem.py
+++ b/tests/models/test_problem.py
@@ -17,6 +17,7 @@ class TestProblem(M.Problem):
 @pytest.mark.parametrize('text,value,exc', [
     ('FOO: 42\nBAR: answer', {'foo': 42, 'bar': 'answer'}, None),
     ('FOO: 4.2\nBAR: answer', None, E.ParsingError),
+    ('FOO: 42\nBAR: answer\nEOF\n', {'foo': 42, 'bar': 'answer'}, None)
 ])
 def test_model_parse(TestProblem, text, value, exc):
     if exc:
@@ -29,8 +30,8 @@ def test_model_parse(TestProblem, text, value, exc):
 
 
 @pytest.mark.parametrize('value,text,exc', [
-    ({'foo': 42, 'bar': 'answer'}, 'FOO: 42\nBAR: answer\nEOF', None),
-    ({'foo': 42, 'bar': 'answer', 'baz': 'wat'}, 'FOO: 42\nBAR: answer\nEOF', None),  # noqa: E501
+    ({'foo': 42, 'bar': 'answer'}, 'FOO: 42\nBAR: answer\nEOF\n', None),
+    ({'foo': 42, 'bar': 'answer', 'baz': 'wat'}, 'FOO: 42\nBAR: answer\nEOF\n', None),  # noqa: E501
 ])
 def test_model_render(TestProblem, value, text, exc):
     problem = TestProblem(**value)
diff --git a/tsplib95/fields.py b/tsplib95/fields.py
index db9b41b..7de9b88 100644
--- a/tsplib95/fields.py
+++ b/tsplib95/fields.py
@@ -238,7 +238,7 @@ class AdjacencyListField(TransformerField):
     def build_transformer(cls):
         return T.MapT(key=T.FuncT(func=int),
                       value=T.ListT(value=T.FuncT(func=int)),
-                      sep="\n",
+                      sep=('-1', ' -1\n'),
                       terminal='-1')
 
 
@@ -249,7 +249,7 @@ class EdgeListField(TransformerField):
 
     @classmethod
     def build_transformer(cls):
-        edge = T.TupleT(value=T.FuncT(func=int), size=2)
+        edge = T.ListT(value=T.FuncT(func=int), size=2)
         return T.ListT(value=edge, terminal='-1', sep='\n')
 
 
@@ -273,7 +273,7 @@ class EdgeDataField(TransformerField):
     def build_transformer(cls):
         adj_list = AdjacencyListField.build_transformer()
         edge_list = EdgeListField.build_transformer()
-        return T.UnionT(edge_list, adj_list)
+        return T.UnionT(adj_list, edge_list)
 
 
 class DepotsField(TransformerField):
diff --git a/tsplib95/models.py b/tsplib95/models.py
index 1eb7223..450fa45 100644
--- a/tsplib95/models.py
+++ b/tsplib95/models.py
@@ -112,7 +112,7 @@ def parse(cls, text, **options):
         # parse into a dictionary
         data = {}
         for keyword, value in zip(field_keywords, field_values):
-            if keyword != 'EOF':
+            if keyword and keyword != 'EOF':
                 field = cls.fields_by_keyword[keyword]
                 name = cls.names_by_keyword[keyword]
                 data[name] = field.parse(value.strip())
@@ -228,7 +228,7 @@ def render(self):
         for keyword, value in rendered.items():
             sep = ':\n' if '\n' in value else ': '
             kvpairs.append(f'{keyword}{sep}{value}')
-        kvpairs.append('EOF')
+        kvpairs.append('EOF\n')
 
         # join and return the result
         return '\n'.join(kvpairs)
diff --git a/tsplib95/transformers.py b/tsplib95/transformers.py
index a2dc33d..7536349 100644
--- a/tsplib95/transformers.py
+++ b/tsplib95/transformers.py
@@ -244,14 +244,6 @@ def pack(self, items):
     def unpack(self, container):
         return list(container)
 
-class TupleT(ContainerT):
-    """Transformer for tuples"""
-
-    def pack(self, items):
-        return tuple(items)
-
-    def unpack(self, container):
-        return tuple(container)
 
 class MapT(ContainerT):
     """Transformer for a key-value mapping of items.