ast.literal_eval can properly evaluate complex numbers now. This fixes issue4907.

Lib/ast.py

@@ -64,6 +64,18 @@ def _convert(node):
         elif isinstance(node, Name):
             if node.id in _safe_names:
                 return _safe_names[node.id]
+        elif isinstance(node, BinOp) and \
+             isinstance(node.op, (Add, Sub)) and \
+             isinstance(node.right, Num) and \
+             isinstance(node.right.n, complex) and \
+             isinstance(node.left, Num) and \
+             isinstance(node.left.n, (int, long, float)):
+            left = node.left.n
+            right = node.right.n
+            if isinstance(node.op, Add):
+                return left + right
+            else:
+                return left - right
         raise ValueError('malformed string')
     return _convert(node_or_string)
 

Lib/test/test_ast.py

@@ -271,6 +271,17 @@ def test_literal_eval(self):
         self.assertEqual(ast.literal_eval('(True, False, None)'), (True, False, None))
         self.assertRaises(ValueError, ast.literal_eval, 'foo()')
 
+    def test_literal_eval_issue4907(self):
+        self.assertEqual(ast.literal_eval('2j'), 2j)
+        self.assertEqual(ast.literal_eval('10 + 2j'), 10 + 2j)
+        self.assertEqual(ast.literal_eval('1.5 - 2j'), 1.5 - 2j)
+        try:
+            ast.literal_eval('2 + (3 + 4j)')
+        except ValueError:
+            pass
+        else:
+            self.fail('expected value error')
+
 
 def test_main():
     test_support.run_unittest(AST_Tests, ASTHelpers_Test)