fix: redundant minus sign added to negative integers when multiplie by -1
Fix #346

Signed-off-by: Frost Ming <me@frostming.com>
GitOrigin-RevId: 990e325d72b96e3d8e34d2dc5224a64a444c5d12
Change-Id: Icc32a0a9278dbb8edb22607cbf4cbd917f8e678b
diff --git a/tomlkit/items.py b/tomlkit/items.py
index 60b13ca..ef40a15 100644
--- a/tomlkit/items.py
+++ b/tomlkit/items.py
@@ -619,9 +619,8 @@
 
     def _new(self, result):
         raw = str(result)
-        if self._sign:
-            sign = "+" if result >= 0 else "-"
-            raw = sign + raw
+        if self._sign and result >= 0:
+            raw = f"+{raw}"
 
         return Integer(result, self._trivia, raw)