Replace StringComparer.InvariantCultrueIgnoreCase with...

Replace StringComparer.InvariantCultrueIgnoreCase with STringComparer.OrdinalIgnoreCase as the former is almost always incorrect for string equality.

StackExchange.Redis/StackExchange/Redis/CommandMap.cs

@@ -85,8 +85,7 @@ public static CommandMap Create(Dictionary<string, string> overrides)
         {
             if (overrides == null || overrides.Count == 0) return Default;
 
-            if (ReferenceEquals(overrides.Comparer, StringComparer.OrdinalIgnoreCase) ||
-                ReferenceEquals(overrides.Comparer, StringComparer.InvariantCultureIgnoreCase))
+            if (ReferenceEquals(overrides.Comparer, StringComparer.OrdinalIgnoreCase))
             {
                 // that's ok; we're happy with ordinal/invariant case-insensitive
                 // (but not culture-specific insensitive; completely untested)

StackExchange.Redis/StackExchange/Redis/ConfigurationOptions.cs

@@ -87,7 +87,7 @@ internal static void Unknown(string key)
                 ConfigChannel, AbortOnConnectFail, ResolveDns,
                 ChannelPrefix, Proxy, ConnectRetry,
                 ConfigCheckSeconds, DefaultDatabase,
-            }.ToDictionary(x => x, StringComparer.InvariantCultureIgnoreCase);
+            }.ToDictionary(x => x, StringComparer.OrdinalIgnoreCase);
 
             public static string TryNormalize(string value)
             {
@@ -401,7 +401,7 @@ internal bool HasDnsEndPoints()
 #pragma warning disable 1998 // NET40 is sync, not async, currently
         internal async Task ResolveEndPointsAsync(ConnectionMultiplexer multiplexer, TextWriter log)
         {
-            Dictionary<string, IPAddress> cache = new Dictionary<string, IPAddress>(StringComparer.InvariantCultureIgnoreCase);
+            Dictionary<string, IPAddress> cache = new Dictionary<string, IPAddress>(StringComparer.OrdinalIgnoreCase);
             for (int i = 0; i < endpoints.Count; i++)
             {
                 var dns = endpoints[i] as DnsEndPoint;
@@ -598,7 +598,7 @@ private void DoParse(string configuration, bool ignoreUnknown)
                                 var cmdName = option.Substring(1, idx - 1);
                                 if (Enum.TryParse(cmdName, true, out cmd))
                                 {
-                                    if (map == null) map = new Dictionary<string, string>(StringComparer.InvariantCultureIgnoreCase);
+                                    if (map == null) map = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
                                     map[cmdName] = value;
                                 }
                             }

StackExchange.Redis/StackExchange/Redis/ConnectionMultiplexer.cs

@@ -1447,7 +1447,7 @@ private async Task<ServerEndPoint> NominatePreferredMaster(TextWriter log, Serve
             Dictionary<string, int> uniques = null;
             if (useTieBreakers)
             {   // count the votes
-                uniques = new Dictionary<string, int>(StringComparer.InvariantCultureIgnoreCase);
+                uniques = new Dictionary<string, int>(StringComparer.OrdinalIgnoreCase);
                 await WaitAllIgnoreErrorsAsync(tieBreakers, 50, log).ForAwait();
                 for (int i = 0; i < tieBreakers.Length; i++)
                 {