Ensure brackets are correct (even if there are too many)

scikit-hep · Feb 11, 2018 · 64bd3f4 · 64bd3f4
1 parent c29bc82
commit 64bd3f4
Show file tree

Hide file tree

Showing 2 changed files with 8 additions and 3 deletions.
diff --git a/formulate/parser.py b/formulate/parser.py
@@ -208,7 +208,7 @@ def to_string(self, expression, config):
             return self.op + args[0]
         else:
             assert len(args) >= 2, args
-            return (' '+self.op+' ').join(args)
+            return '('+(' '+self.op+' ').join(args)+')'
 
 
 class Parser(object):
@@ -237,7 +237,10 @@ def to_expression(self, string):
             return result
 
     def to_string(self, expression):
-        return expression.to_string({x.id: x for x in self._config})
+        result = expression.to_string({x.id: x for x in self._config})
+        if result.startswith('(') and result.endswith(')'):
+            result = result[1:-1]
+        return result
 
 
 class ParsingException(Exception):

diff --git a/tests/utils.py b/tests/utils.py
@@ -16,7 +16,9 @@ def check_result(input_string, expected_expression, expected_string=None, **kwar
         string = to_func(result)
 
         assert_equal_expressions(result, expected_expression)
-        assert string.replace(' ', '') == expected_string.replace(' ', ''), (string, expected_string)
+        # TODO Stop stripping parentheses
+        assert (string.replace(' ', '').replace('(', '').replace(')', '') ==
+                expected_string.replace(' ', '').replace('(', '').replace(')', '')), (string, expected_string)
     return check_result