User defined separators for permutations formating

Author: elmar-hinz

challenges/challenge.py

@@ -378,10 +378,12 @@ def format_path(self, integers, backwards=False):
             joint = '->'
         return self.format_list_of_integers(integers, joint)
 
-    def format_permutations(self, permutations):
+    def format_permutations(self, permutations, separator = '\n',
+                            element_separator = ' '):
         output = ''
         for perm in permutations:
             output += '('
-            output += ' '.join(('+' if i > 0 else '') + str(i) for i in perm)
-            output += ')' + self.br
-        return output[:-1]
+            output += element_separator.join(
+                ('+' if i > 0 else '') + str(i) for i in perm)
+            output += ')' + separator
+        return output[:-len(separator)]

tests/test_challenge.py

@@ -285,3 +285,14 @@ def test_format_permuations(self):
         actual = self.challenge.format_permutations(list)
         expect = '(+1 -2)\n(-3 +4)'
         self.assertEqual(expect, actual)
+
+    def test_format_permuations_with_user_defined_joint(self):
+        """Show user defined separators can be used."""
+        list = [[1, -2], [-3, 4]]
+        actual = self.challenge.format_permutations(
+            list,
+            separator = ', ',
+            element_separator = ' | '
+        )
+        expect = '(+1 | -2), (-3 | +4)'
+        self.assertEqual(expect, actual)