From 404bcf3693f4ce4da571ff6816e65cbd3471e7c8 Mon Sep 17 00:00:00 2001
From: Vlada Shubina <vshubina@microsoft.com>
Date: Mon, 5 Sep 2022 11:50:28 +0200
Subject: [PATCH] fixed null reference exception in Token operator overload

---
 src/System.CommandLine/Parsing/Token.cs | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/System.CommandLine/Parsing/Token.cs b/src/System.CommandLine/Parsing/Token.cs
index 7b656c9886..9fae4842ac 100644
--- a/src/System.CommandLine/Parsing/Token.cs
+++ b/src/System.CommandLine/Parsing/Token.cs
@@ -66,7 +66,7 @@ internal Token(string? value, TokenType type, Symbol? symbol, int position)
         /// <param name="left">The first <see cref="Token"/>.</param>
         /// <param name="right">The second <see cref="Token"/>.</param>
         /// <returns><see langword="true" /> if the objects are equal.</returns>
-        public static bool operator ==(Token left, Token right) => left.Equals(right);
+        public static bool operator ==(Token? left, Token? right) => left is null ? right is null : left.Equals(right);
 
         /// <summary>
         /// Checks if two specified <see cref="Token"/> instances have different values.
@@ -74,6 +74,7 @@ internal Token(string? value, TokenType type, Symbol? symbol, int position)
         /// <param name="left">The first <see cref="Token"/>.</param>
         /// <param name="right">The second <see cref="Token"/>.</param>
         /// <returns><see langword="true" /> if the objects are not equal.</returns>
-        public static bool operator !=(Token left, Token right) => !left.Equals(right);
+        public static bool operator !=(Token? left, Token? right) => left is null ? right is not null : !left.Equals(right);
+
     }
 }