Claims identity and principal debugging update (#87742)

* Claims identity and principal debugging update

* Comment

src/libraries/System.Security.Claims/src/System/Security/Claims/ClaimsIdentity.cs

@@ -946,7 +946,21 @@ namespace System.Security.Claims
                 claimsCount++;
             }
 
-            return $"Identity Name = {Name ?? "(null)"}, IsAuthenticated = {(IsAuthenticated ? "true" : "false")}, Claims Count = {claimsCount}";
+            string debugText = $"IsAuthenticated = {(IsAuthenticated ? "true" : "false")}";
+            if (Name != null)
+            {
+                // The ClaimsIdentity.Name property requires that ClaimsIdentity.NameClaimType is correctly
+                // configured to match the name of the logical name claim type of the identity.
+                // Because of this, only include name if the ClaimsIdentity.Name property has a value.
+                // Not including the name is to avoid developer confusion at seeing "Name = (null)" on an authenticated identity.
+                debugText += $", Name = {Name}";
+            }
+            if (claimsCount > 0)
+            {
+                debugText += $", Claims = {claimsCount}";
+            }
+
+            return debugText;
         }
 
         private sealed class ClaimsIdentityDebugProxy

src/libraries/System.Security.Claims/src/System/Security/Claims/ClaimsPrincipal.cs

@@ -580,19 +580,19 @@ namespace System.Security.Claims
                 identitiesCount++;
             }
 
+            // Return debug string optimized for the case of one identity.
+            if (identitiesCount == 1 && Identity is ClaimsIdentity claimsIdentity)
+            {
+                return claimsIdentity.DebuggerToString();
+            }
+
             int claimsCount = 0;
             foreach (Claim item in Claims)
             {
                 claimsCount++;
             }
 
-            // Return debug string optimized for the case of one identity.
+            return $"Identities = {identitiesCount}, Claims = {claimsCount}";
-            if (identitiesCount == 1 && Identity is ClaimsIdentity claimsIdentity)
-            {
-                return $"Principal {claimsIdentity.DebuggerToString()}";
-            }
-
-            return $"Principal Identities Count: {identitiesCount}, Claims Count: {claimsCount}";
         }
 
         private sealed class ClaimsPrincipalDebugProxy