Fix repeated trace name case.

Author: theengineear

plotly/graph_objs/graph_objs.py

@@ -895,18 +895,20 @@ def get_data(self, flatten=False):
             self.to_graph_objs()
             data = [v.get_data(flatten=flatten) for v in self]
             d = {}
+            taken_names = []
             for i, trace in enumerate(data):
 
                 # we want to give the traces helpful names
                 # however, we need to be sure they're unique too...
                 trace_name = trace.pop('name', 'trace_{}'.format(i))
-                if trace_name in d:
+                if trace_name in taken_names:
                     j = 1
                     new_trace_name = "{}_{}".format(trace_name, j)
-                    while new_trace_name in d:
+                    while new_trace_name in taken_names:
                         new_trace_name = "{}_{}".format(trace_name, j)
                         j += 1
                     trace_name = new_trace_name
+                taken_names.append(trace_name)
 
                 # finish up the dot-concatenation
                 for k, v in trace.items():

plotly/tests/test_core/test_graph_objs/test_get_data.py

@@ -162,3 +162,13 @@ def test_get_data_flatten(self):
         self.assertEqual(flat_data, comp_data)
 
     # TODO test for Data, Scatter, etc..
+
+    def test_flatten_repeated_trace_names(self):
+        dl = Data([Scatter(name='thesame', x=[1, 2, 3]) for _ in range(3)])
+        data = dl.get_data(flatten=True)
+        comp_data = {
+            'thesame.x': [1, 2, 3],
+            'thesame_1.x': [1, 2, 3],
+            'thesame_2.x': [1, 2, 3]
+        }
+        self.assertEqual(data, comp_data)