add tests for prev commit

Author: etpinard

plotly/tests/test_core/test_tools/test_make_subplots.py

@@ -71,13 +71,21 @@ def test_specs_rowspan_too_big():
                                    [{'rowspan': 2}]])
 
 @raises(Exception)
-def test_subplot_insets_wrong_type():
+def test_insets_wrong_type():
     fig = tls.make_subplots(insets="not going to work")
 
 @raises(Exception)
-def test_subplot_insets_wrong_item():
+def test_insets_wrong_item():
     fig = tls.make_subplots(insets=[{'not': "going to work"}])
 
+@raises(Exception)
+def test_insets_wrong_cell_row():
+    fig = tls.make_subplots(insets=([{'cell': (0, 1)}]))
+
+@raises(Exception)
+def test_insets_wrong_cell_col():
+    fig = tls.make_subplots(insets=([{'cell': (1, 0)}]))
+
 def test_get_single_plot():
     expected = Figure(
         data=Data(),