Support more arithmetic operators

Author: githejie

src/mcp_server_calculator/calculator.py

@@ -26,6 +26,7 @@ def eval_expr(node):
             return -eval_expr(node.operand)
         raise ValueError(f"Unsupported operation: {ast.dump(node)}")
 
+    expression = expression.replace('^', '**').replace('×', '*').replace('÷', '/')
     parsed_expr = ast.parse(expression, mode='eval')
     result = eval_expr(parsed_expr.body)
     return str(result)

tests/test_calculator.py

@@ -10,9 +10,11 @@ def test_subtraction(self):
 
     def test_multiplication(self):
         self.assertEqual(evaluate("2 * 3"), "6")
+        self.assertEqual(evaluate("2 × 3"), "6")
 
     def test_division(self):
         self.assertEqual(evaluate("8 / 2"), "4.0")
+        self.assertEqual(evaluate("8 ÷ 2"), "4.0")
 
     def test_floor_division(self):
         self.assertEqual(evaluate("7 // 2"), "3")
@@ -22,6 +24,7 @@ def test_modulus(self):
 
     def test_power(self):
         self.assertEqual(evaluate("2 ** 3"), "8")
+        self.assertEqual(evaluate("2 ^ 3"), "8")
 
     def test_unary_minus(self):
         self.assertEqual(evaluate("-5"), "-5")