Set severity of rule CA1870 to warning

eng/CodeAnalysis.src.globalconfig

@@ -489,6 +489,9 @@ dotnet_diagnostic.CA1868.severity = warning
 # CA1869: Cache and reuse 'JsonSerializerOptions' instances
 dotnet_diagnostic.CA1869.severity = warning
 
+# CA1870: Use a cached 'SearchValues' instance
+dotnet_diagnostic.CA1870.severity = warning
+
 # CA2000: Dispose objects before losing scope
 dotnet_diagnostic.CA2000.severity = none
 

eng/CodeAnalysis.test.globalconfig

@@ -486,6 +486,9 @@ dotnet_diagnostic.CA1868.severity = none
 # CA1869: Cache and reuse 'JsonSerializerOptions' instances
 dotnet_diagnostic.CA1869.severity = none
 
+# CA1870: Use a cached 'SearchValues' instance
+dotnet_diagnostic.CA1870.severity = none
+
 # CA2000: Dispose objects before losing scope
 dotnet_diagnostic.CA2000.severity = none
 

src/coreclr/nativeaot/System.Private.CoreLib/src/System/Reflection/Runtime/General/Helpers.cs

@@ -109,7 +109,12 @@ public static TypeLoadException CreateTypeLoadException(string typeName, string
         public static string EscapeTypeNameIdentifier(this string identifier)
         {
             // Some characters in a type name need to be escaped
+
+            // We're avoiding calling into MemoryExtensions here as it has paths that lead to reflection,
+            // and that would lead to an infinite loop given that this is the implementation of reflection.
+#pragma warning disable CA1870 // Use a cached 'SearchValues' instance
             if (identifier != null && identifier.IndexOfAny(s_charsToEscape) != -1)
+#pragma warning restore CA1870
             {
                 StringBuilder sbEscapedName = new StringBuilder(identifier.Length);
                 foreach (char c in identifier)

src/libraries/System.Configuration.ConfigurationManager/src/System/Configuration/BaseConfigurationRecord.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Buffers;
 using System.Collections;
 using System.Collections.Generic;
 using System.Collections.Specialized;
@@ -18,6 +19,12 @@ namespace System.Configuration
     [DebuggerDisplay("ConfigPath = {ConfigPath}")]
     internal abstract class BaseConfigurationRecord : IInternalConfigRecord
     {
+#if NET8_0_OR_GREATER
+        private static readonly SearchValues<char> s_invalidSubPathChars = SearchValues.Create(InvalidSubPathCharactersString);
+#else
+        private static ReadOnlySpan<char> s_invalidSubPathChars => InvalidSubPathCharactersString.AsSpan();
+#endif
+
         protected const string NewLine = "\r\n";
 
         internal const string KeywordTrue = "true";
@@ -128,7 +135,6 @@ internal abstract class BaseConfigurationRecord : IInternalConfigRecord
 
         // Comparer used in sorting IndirectInputs.
         private static readonly IComparer<SectionInput> s_indirectInputsComparer = new IndirectLocationInputComparer();
-        private static readonly char[] s_invalidSubPathCharactersArray = InvalidSubPathCharactersString.ToCharArray();
         protected Hashtable _children; // configName -> record
 
         private object _configContext; // Context for config level
@@ -3090,7 +3096,7 @@ internal static string NormalizeLocationSubPath(string subPath, IConfigErrorInfo
                 throw new ConfigurationErrorsException(SR.Config_location_path_invalid_last_character, errorInfo);
 
             // combination of URI reserved characters and OS invalid filename characters, minus / (allowed reserved character)
-            if (subPath.IndexOfAny(s_invalidSubPathCharactersArray) != -1)
+            if (subPath.AsSpan().IndexOfAny(s_invalidSubPathChars) >= 0)
                 throw new ConfigurationErrorsException(SR.Config_location_path_invalid_character, errorInfo);
 
             return subPath;

src/libraries/System.Reflection.MetadataLoadContext/src/System/Reflection/TypeLoading/General/Helpers.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Buffers;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
 using System.Diagnostics;
@@ -11,6 +12,12 @@ namespace System.Reflection.TypeLoading
 {
     internal static class Helpers
     {
+#if NET8_0_OR_GREATER
+        private static readonly SearchValues<char> s_charsToEscape = SearchValues.Create("\\[]+*&,");
+#else
+        private static ReadOnlySpan<char> s_charsToEscape => "\\[]+*&,".AsSpan();
+#endif
+
         [return: NotNullIfNotNull(nameof(original))]
         public static T[]? CloneArray<T>(this T[]? original)
         {
@@ -96,7 +103,7 @@ public static string ComputeArraySuffix(int rank, bool multiDim)
         public static string EscapeTypeNameIdentifier(this string identifier)
         {
             // Some characters in a type name need to be escaped
-            if (identifier.IndexOfAny(s_charsToEscape) != -1)
+            if (TypeNameContainsTypeParserMetacharacters(identifier))
             {
                 StringBuilder sbEscapedName = new StringBuilder(identifier.Length);
                 foreach (char c in identifier)
@@ -113,12 +120,16 @@ public static string EscapeTypeNameIdentifier(this string identifier)
 
         public static bool TypeNameContainsTypeParserMetacharacters(this string identifier)
         {
-            return identifier.IndexOfAny(s_charsToEscape) != -1;
+            return identifier.AsSpan().IndexOfAny(s_charsToEscape) >= 0;
         }
 
         public static bool NeedsEscapingInTypeName(this char c)
         {
-            return Array.IndexOf(s_charsToEscape, c) >= 0;
+#if NET8_0_OR_GREATER
+            return s_charsToEscape.Contains(c);
+#else
+            return s_charsToEscape.IndexOf(c) >= 0;
+#endif
         }
 
         public static string UnescapeTypeNameIdentifier(this string identifier)
@@ -145,8 +156,6 @@ public static string UnescapeTypeNameIdentifier(this string identifier)
             return identifier;
         }
 
-        private static readonly char[] s_charsToEscape = new char[] { '\\', '[', ']', '+', '*', '&', ',' };
-
         /// <summary>
         /// For AssemblyReferences, convert "unspecified" components from the ECMA format (0xffff) to the in-memory System.Version format (0xffffffff).
         /// </summary>

src/libraries/System.Speech/src/Recognition/SrgsGrammar/SrgsRule.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Buffers;
 using System.Collections.ObjectModel;
 using System.Diagnostics;
 using System.Speech.Internal;
@@ -14,6 +15,8 @@ namespace System.Speech.Recognition.SrgsGrammar
     [DebuggerTypeProxy(typeof(SrgsRuleDebugDisplay))]
     public class SrgsRule : IRule
     {
+        private static readonly SearchValues<char> s_invalidChars = SearchValues.Create("?*+|()^$/;.=<>[]{}\\ \t\r\n");
+
         #region Constructors
         private SrgsRule()
         {
@@ -383,7 +386,7 @@ private void ValidateIdentifier(string s)
                 XmlParser.ThrowSrgsException(SRID.ConstructorNotAllowed, _id);
             }
 
-            if (s != null && (s.IndexOfAny(s_invalidChars) >= 0 || s.Length == 0))
+            if (s != null && (s.Length == 0 || s.AsSpan().ContainsAny(s_invalidChars)))
             {
                 XmlParser.ThrowSrgsException(SRID.InvalidMethodName);
             }
@@ -416,7 +419,6 @@ private void ValidateIdentifier(string s)
         private string _onError;
 
         private string _onRecognition;
-        private static readonly char[] s_invalidChars = new char[] { '?', '*', '+', '|', '(', ')', '^', '$', '/', ';', '.', '=', '<', '>', '[', ']', '{', '}', '\\', ' ', '\t', '\r', '\n' };
 
         #endregion