Add Python 3.8 to Travis CI config (#2142)

* Add Python 3.8 to Travis CI

* Change assert statement to fix a deprecation warning

Author: tqa236

.travis.yml

@@ -1,10 +1,11 @@
 language: python
 dist: xenial
-  
+
 python:
   - 3.5
   - 3.6
   - 3.7
+  - 3.8
   - nightly
 
 matrix:
@@ -42,6 +43,6 @@ matrix:
 
 before_script:
   - flake8
-  
-script: 
+
+script:
   - ./test/check-exercises.py

exercises/pov/.meta/template.j2

@@ -23,7 +23,7 @@
 {%- macro test_path_to(case) -%}
         {% if case["expected"] -%}
         expected = {{ case["expected"] }}
-        self.assertEquals(tree.{{ case["property"] | to_snake }}("{{ case["input"]["from"] }}", "{{ case["input"]["to"]}}"), expected)
+        self.assertEqual(tree.{{ case["property"] | to_snake }}("{{ case["input"]["from"] }}", "{{ case["input"]["to"]}}"), expected)
         {% else -%}
         with self.assertRaisesWithMessage(ValueError):
             tree.{{ case["property"] | to_snake }}("{{ case["input"]["from"] }}", "{{ case["input"]["to"]}}")

exercises/pov/pov_test.py

@@ -92,12 +92,12 @@ def test_errors_if_target_does_not_exist_in_a_large_tree(self):
     def test_can_find_path_to_parent(self):
         tree = Tree("parent", [Tree("x"), Tree("sibling")])
         expected = ["x", "parent"]
-        self.assertEquals(tree.path_to("x", "parent"), expected)
+        self.assertEqual(tree.path_to("x", "parent"), expected)
 
     def test_can_find_path_to_sibling(self):
         tree = Tree("parent", [Tree("a"), Tree("x"), Tree("b"), Tree("c")])
         expected = ["x", "parent", "b"]
-        self.assertEquals(tree.path_to("x", "b"), expected)
+        self.assertEqual(tree.path_to("x", "b"), expected)
 
     def test_can_find_path_to_cousin(self):
         tree = Tree(
@@ -115,20 +115,20 @@ def test_can_find_path_to_cousin(self):
             ],
         )
         expected = ["x", "parent", "grandparent", "uncle", "cousin-1"]
-        self.assertEquals(tree.path_to("x", "cousin-1"), expected)
+        self.assertEqual(tree.path_to("x", "cousin-1"), expected)
 
     def test_can_find_path_not_involving_root(self):
         tree = Tree(
             "grandparent",
             [Tree("parent", [Tree("x"), Tree("sibling-0"), Tree("sibling-1")])],
         )
         expected = ["x", "parent", "sibling-1"]
-        self.assertEquals(tree.path_to("x", "sibling-1"), expected)
+        self.assertEqual(tree.path_to("x", "sibling-1"), expected)
 
     def test_can_find_path_from_nodes_other_than_x(self):
         tree = Tree("parent", [Tree("a"), Tree("x"), Tree("b"), Tree("c")])
         expected = ["a", "parent", "c"]
-        self.assertEquals(tree.path_to("a", "c"), expected)
+        self.assertEqual(tree.path_to("a", "c"), expected)
 
     def test_errors_if_destination_does_not_exist(self):
         tree = Tree(