Backport `string.Contains(char)` and `string.EndsWith(char)`

src/BizHawk.BizInvoke/BizInvoker.cs

@@ -8,6 +8,7 @@ using System.Text;
 
 using BizHawk.Common;
 using BizHawk.Common.CollectionExtensions;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.BizInvoke
 {
@@ -534,7 +535,7 @@ namespace BizHawk.BizInvoke
 					throw new NotImplementedException("Multidimensional arrays are not supported!");
 				}
 
-				if (type.Name.Contains('*'))
+				if (type.Name.ContainsOrdinal('*'))
 				{
 					throw new NotImplementedException("Only 0-based 1-dimensional arrays are supported!");
 				}

src/BizHawk.Client.EmuHawk/EmuHawkUtil.cs

@@ -3,6 +3,7 @@ using System.IO;
 using System.Security.Principal;
 
 using BizHawk.Common;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Client.EmuHawk
 {
@@ -15,7 +16,7 @@ namespace BizHawk.Client.EmuHawk
 		/// <remarks>http://stackoverflow.com/questions/139010/how-to-resolve-a-lnk-in-c-sharp</remarks>
 		public static string ResolveShortcut(string filename)
 		{
-			if (OSTailoredCode.IsUnixHost || filename.Contains("|")
+			if (OSTailoredCode.IsUnixHost || filename.ContainsOrdinal('|')
 				|| !".lnk".Equals(Path.GetExtension(filename), StringComparison.OrdinalIgnoreCase))
 			{
 				return filename; // archive internal files are never shortcuts (and choke when analyzing any further)

src/BizHawk.Client.EmuHawk/RetroAchievements/RCheevos.Debug.cs

@@ -8,6 +8,7 @@ using System.Windows.Forms;
 using BizHawk.Client.Common;
 using BizHawk.Common;
 using BizHawk.Common.PathExtensions;
+using BizHawk.Common.StringExtensions;
 using BizHawk.Emulation.Common;
 using BizHawk.Emulation.Cores.Arcades.MAME;
 using BizHawk.Emulation.DiscSystem;
@@ -310,7 +311,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			static string ResolvePath(string path)
 			{
-				if (path.IndexOf('|') == -1 && Disc.IsValidExtension(Path.GetExtension(path)))
+				if (!path.ContainsOrdinal('|') && Disc.IsValidExtension(Path.GetExtension(path)))
 				{
 					return path; // nothing to do in this case
 				}
@@ -342,7 +343,7 @@ namespace BizHawk.Client.EmuHawk
 
 			static ConsoleID IdentifyConsole(string path)
 			{
-				if (path.IndexOf('|') == -1 && Disc.IsValidExtension(Path.GetExtension(path)))
+				if (!path.ContainsOrdinal('|') && Disc.IsValidExtension(Path.GetExtension(path)))
 				{
 					using var disc = DiscExtensions.CreateAnyType(path, Console.WriteLine);
 					if (disc is null)

src/BizHawk.Client.EmuHawk/tools/MultiDiskBundler/MultiDiskBundler.cs

@@ -61,7 +61,7 @@ namespace BizHawk.Client.EmuHawk
 
 			if (!Game.IsNullInstance())
 			{
-				if (MainForm.CurrentlyOpenRom.Contains("|"))
+				if (MainForm.CurrentlyOpenRom.ContainsOrdinal('|'))
 				{
 					var pieces = MainForm.CurrentlyOpenRom.Split('|');
 

src/BizHawk.Common/DeepEquality.cs

@@ -1,8 +1,9 @@
 using System;
 using System.Collections.Generic;
-using System.Linq;
 using System.Reflection;
 
+using BizHawk.Common.StringExtensions;
+
 namespace BizHawk.Common
 {
 	/// <summary>Annotated fields will not be used by <see cref="DeepEquality"/> for comparison.</summary>
@@ -24,7 +25,7 @@ namespace BizHawk.Common
 			}
 
 			// is there a better way to do this?  i couldn't find any documentation...
-			return t.ToString().Contains('*');
+			return t.ToString().ContainsOrdinal('*');
 		}
 
 		/// <summary>

src/BizHawk.Common/Extensions/StringExtensions.cs

@@ -13,9 +13,31 @@ namespace BizHawk.Common.StringExtensions
 			return new(a);
 		}
 
+#if !(NETSTANDARD2_1_OR_GREATER || NETCOREAPP2_1_OR_GREATER)
+		public static bool Contains(this string haystack, char needle)
+			=> haystack.IndexOf(needle) >= 0;
+#endif
+
 		public static bool Contains(this string haystack, string needle, StringComparison comparisonType)
 			=> haystack.IndexOf(needle, comparisonType) != -1;
 
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		public static bool ContainsOrdinal(this string haystack, char needle)
+			=> haystack.Contains(needle); // already ordinal
+
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		public static bool ContainsOrdinal(this string haystack, string needle)
+			=> haystack.Contains(needle); // already ordinal
+
+#if !(NETSTANDARD2_1_OR_GREATER || NETCOREAPP2_1_OR_GREATER)
+		public static bool EndsWith(this string haystack, char needle)
+			=> haystack.Length >= 1 && haystack[^1] == needle;
+#endif
+
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		public static bool EndsWithOrdinal(this string haystack, char needle)
+			=> haystack.EndsWith(needle); // already ordinal
+
 		/// <returns>
 		/// <see langword="true"/> if <paramref name="str"/> appears in <paramref name="options"/> (case-insensitive)
 		/// </returns>

src/BizHawk.Common/FFmpegService.cs

@@ -8,6 +8,7 @@ using System.Text.RegularExpressions;
 using System.IO;
 using System.Threading.Tasks;
 using BizHawk.Common.PathExtensions;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Common
 {
@@ -29,9 +30,7 @@ namespace BizHawk.Common
 		}
 
 		private static string[] Escape(IEnumerable<string> args)
-		{
+			=> args.Select(static s => s.ContainsOrdinal(' ') ? $"\"{s}\"" : s).ToArray();
-			return args.Select(s => s.Contains(" ") ? $"\"{s}\"" : s).ToArray();
-		}
 
 		//note: accepts . or : in the stream stream/substream separator in the stream ID format, since that changed at some point in FFMPEG history
 		//if someone has a better idea how to make the determination of whether an audio stream is available, I'm all ears

src/BizHawk.Emulation.Cores/Arcades/MAME/MAME.IInputPollable.cs

@@ -1,6 +1,5 @@
 using System;
 using System.Collections.Generic;
-using System.Linq;
 
 using BizHawk.Common;
 using BizHawk.Common.StringExtensions;
@@ -47,7 +46,7 @@ namespace BizHawk.Emulation.Cores.Arcades.MAME
 
 			foreach (var buttonField in buttonFields)
 			{
-				if (buttonField != string.Empty && !buttonField.Contains('%'))
+				if (buttonField.Length is not 0 && !buttonField.ContainsOrdinal('%'))
 				{
 					var tag = buttonField.SubstringBefore(',');
 					var field = buttonField.SubstringAfterLast(',');
@@ -66,7 +65,7 @@ namespace BizHawk.Emulation.Cores.Arcades.MAME
 
 			foreach (var analogField in analogFields)
 			{
-				if (analogField != string.Empty && !analogField.Contains('%'))
+				if (analogField.Length is not 0 && !analogField.ContainsOrdinal('%'))
 				{
 					var keys = analogField.Split(',');
 					var tag = keys[0];

src/BizHawk.Emulation.Cores/Arcades/MAME/MAME.ISettable.cs

@@ -166,7 +166,7 @@ namespace BizHawk.Emulation.Cores.Arcades.MAME
 					}
 					else
 					{
-						if (hashdata.Contains("^"))
+						if (hashdata.EndsWithOrdinal('^'))
 						{
 							hashdata = hashdata.RemoveSuffix("^");
 							name += " (BAD DUMP)";

src/BizHawk.Emulation.Cores/Arcades/MAME/MAMEMachineDB.cs

@@ -2,10 +2,10 @@ using System;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO;
-using System.Linq;
 using System.Threading;
 
 using BizHawk.Common;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Emulation.Cores.Arcades.MAME
 {
@@ -54,7 +54,7 @@ namespace BizHawk.Emulation.Cores.Arcades.MAME
 		public static bool IsMAMEMachine(string path)
 		{
 			if (_acquire == null) throw new InvalidOperationException("MAME Machine DB not initialized. It's a client responsibility because only a client knows where the database is located.");
-			if (path.Contains('|')) return false; // binded archive, can't be a mame zip (note | is not a legal filesystem char, at least on windows)
+			if (path.ContainsOrdinal('|')) return false; // binded archive, can't be a mame zip (note | is not a legal filesystem char, at least on windows)
 			if (Path.GetExtension(path).ToLowerInvariant() is not ".zip" and not ".7z") return false;
 			_acquire.WaitOne();
 			return Instance.MachineDB.Contains(Path.GetFileNameWithoutExtension(path).ToLowerInvariant());

src/BizHawk.Emulation.Cores/CPUs/FairchildF8/F3850.Disassembler.cs

@@ -1,5 +1,7 @@
 using System;
 using System.Collections.Generic;
+
+using BizHawk.Common.StringExtensions;
 using BizHawk.Emulation.Common;
 
 namespace BizHawk.Emulation.Cores.Components.FairchildF8
@@ -15,17 +17,16 @@ namespace BizHawk.Emulation.Cores.Components.FairchildF8
 			//n immediate succeeds the opcode and the displacement (if present)
 			//nn immediately succeeds the opcode and the displacement (if present)
 
-			if (format.IndexOf("nn", StringComparison.Ordinal) != -1)
+			if (format.ContainsOrdinal("nn"))
 			{
 				format = format.Replace("nn", read(addr++)
 					.ToString("X2") + read(addr++)
 					.ToString("X2") + "h"); // MSB is read first
 			}
+			if (format.ContainsOrdinal('n')) format = format.Replace("n", $"{read(addr++):X2}h");
 
-			if (format.IndexOf("n", StringComparison.Ordinal) != -1) format = format.Replace("n", $"{read(addr++):X2}h");
+			format = format.Replace("+d", "d");
-
+			if (format.ContainsOrdinal('d'))
-			if (format.IndexOf("+d", StringComparison.Ordinal) != -1) format = format.Replace("+d", "d");
-			if (format.IndexOf("d", StringComparison.Ordinal) != -1)
 			{
 				var b = unchecked((sbyte)read(addr++));
 				format = format.Replace("d", $"{(b < 0 ? '-' : '+')}{(b < 0 ? -b : b):X2}h");

src/BizHawk.Emulation.Cores/CPUs/Z80A/NewDisassembler.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 
+using BizHawk.Common.StringExtensions;
 using BizHawk.Emulation.Common;
 
 namespace BizHawk.Emulation.Cores.Components.Z80A
@@ -13,11 +14,11 @@ namespace BizHawk.Emulation.Cores.Components.Z80A
 			//n immediate succeeds the opcode and the displacement (if present)
 			//nn immediately succeeds the opcode and the displacement (if present)
 
-			if (format.IndexOf("nn", StringComparison.Ordinal) != -1) format = format.Replace("nn", $"{read(addr++) + (read(addr++) << 8):X4}h"); // LSB is read first
+			if (format.ContainsOrdinal("nn")) format = format.Replace("nn", $"{read(addr++) + (read(addr++) << 8):X4}h"); // LSB is read first
-			if (format.IndexOf("n", StringComparison.Ordinal) != -1) format = format.Replace("n", $"{read(addr++):X2}h");
+			if (format.ContainsOrdinal('n')) format = format.Replace("n", $"{read(addr++):X2}h");
 
-			if (format.IndexOf("+d", StringComparison.Ordinal) != -1) format = format.Replace("+d", "d");
+			format = format.Replace("+d", "d");
-			if (format.IndexOf("d", StringComparison.Ordinal) != -1)
+			if (format.ContainsOrdinal('d'))
 			{
 				var b = unchecked ((sbyte) read(addr++));
 				format = format.Replace("d", $"{(b < 0 ? '-' : '+')}{(b < 0 ? -b : b):X2}h");

src/BizHawk.Emulation.Cores/Consoles/Nintendo/3DS/Encore.cs

@@ -7,6 +7,7 @@ using System.Text;
 
 using BizHawk.BizInvoke;
 using BizHawk.Common;
+using BizHawk.Common.StringExtensions;
 using BizHawk.Emulation.Common;
 
 namespace BizHawk.Emulation.Cores.Consoles.Nintendo.N3DS
@@ -46,7 +47,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.N3DS
 		[CoreConstructor(VSystemID.Raw.N3DS)]
 		public Encore(CoreLoadParameters<EncoreSettings, EncoreSyncSettings> lp)
 		{
-			if (lp.Roms.Exists(r => r.RomPath.Contains("|")))
+			if (lp.Roms.Exists(static r => r.RomPath.ContainsOrdinal('|')))
 			{
 				throw new InvalidOperationException("3DS does not support compressed ROMs");
 			}