Remove need to allocate new list to find the index

Author: JimBobSquarePants

src/ImageSharp.Web/Commands/CommandCollection.cs

@@ -4,6 +4,7 @@
 using System;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
+using System.Runtime.CompilerServices;
 
 namespace SixLabors.ImageSharp.Web.Commands
 {
@@ -59,7 +60,8 @@ public IEnumerable<string> Keys
                     return item.Value;
                 }
 
-                throw new KeyNotFoundException();
+                ThrowKeyNotFound();
+                return default;
             }
 
             set
@@ -75,7 +77,43 @@ public IEnumerable<string> Keys
             }
         }
 
+        /// <summary>
+        /// Searches for an element that matches the conditions defined by the specified
+        /// predicate, and returns the zero-based index of the first occurrence within the
+        /// entire <see cref="CommandCollection"/>.
+        /// </summary>
+        /// <param name="match">
+        /// The <see cref="Predicate{T}"/> delegate that defines the conditions of the element to
+        /// search for.
+        /// </param>
+        /// <returns>
+        /// The zero-based index of the first occurrence of an element that matches the conditions
+        /// defined by match, if found; otherwise, -1.
+        /// </returns>
+        /// <exception cref="ArgumentNullException"><paramref name="match"/> is null.</exception>
+        public int FindIndex(Predicate<string> match)
+        {
+            Guard.NotNull(match, nameof(match));
+
+            int index = 0;
+            foreach (KeyValuePair<string, string> item in this)
+            {
+                if (match(item.Key))
+                {
+                    return index;
+                }
+
+                index++;
+            }
+
+            return -1;
+        }
+
         /// <inheritdoc/>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
         protected override string GetKeyForItem(KeyValuePair<string, string> item) => item.Key;
+
+        [MethodImpl(MethodImplOptions.NoInlining)]
+        private static void ThrowKeyNotFound() => throw new KeyNotFoundException();
     }
 }

src/ImageSharp.Web/Processors/WebProcessingExtensions.cs

@@ -34,9 +34,7 @@ public static FormattedImage Process(
             CommandParser commandParser,
             CultureInfo culture)
         {
-            var commandKeys = new List<string>(commands.Keys);
-
-            foreach (IImageWebProcessor processor in processors.GetBySupportedCommands(commandKeys))
+            foreach (IImageWebProcessor processor in processors.GetBySupportedCommands(commands))
             {
                 source = processor.Process(source, logger, commands, commandParser, culture);
             }
@@ -52,7 +50,7 @@ public static FormattedImage Process(
         /// <returns>
         /// The sorted proccessors that supports any of the specified commands.
         /// </returns>
-        public static IEnumerable<IImageWebProcessor> GetBySupportedCommands(this IEnumerable<IImageWebProcessor> processors, List<string> commands)
+        public static IEnumerable<IImageWebProcessor> GetBySupportedCommands(this IEnumerable<IImageWebProcessor> processors, CommandCollection commands)
         {
             var indexedProcessors = new List<(int Index, IImageWebProcessor Processor)>();
 

tests/ImageSharp.Web.Tests/Processors/WebProcessingExtensionsTests.cs

@@ -1,8 +1,8 @@
 // Copyright (c) Six Labors.
 // Licensed under the Apache License, Version 2.0.
 
-using System.Collections.Generic;
 using System.Linq;
+using SixLabors.ImageSharp.Web.Commands;
 using SixLabors.ImageSharp.Web.Processors;
 using SixLabors.ImageSharp.Web.Tests.DependencyInjection;
 using Xunit;
@@ -22,14 +22,14 @@ public void WebProcessingExtensions_GetBySupportedCommands()
                 new MockWebProcessor()
             };
 
-            var commands = new List<string>
+            CommandCollection commands = new()
             {
-                ResizeWebProcessor.Width,
-                QualityWebProcessor.Quality,
-                ResizeWebProcessor.Height
+                new(ResizeWebProcessor.Width, null),
+                new(QualityWebProcessor.Quality, null),
+                new(ResizeWebProcessor.Height, null)
             };
 
-            IImageWebProcessor[] supportedProcessors = WebProcessingExtensions.GetBySupportedCommands(processors, commands).ToArray();
+            IImageWebProcessor[] supportedProcessors = processors.GetBySupportedCommands(commands).ToArray();
 
             Assert.Equal(2, supportedProcessors.Length);
             Assert.IsType<ResizeWebProcessor>(supportedProcessors[0]);
@@ -44,9 +44,9 @@ public void WebProcessingExtensions_GetBySupportedCommands_Empty()
                 new MockWebProcessor()
             };
 
-            var commands = new List<string>();
+            CommandCollection commands = new();
 
-            IImageWebProcessor[] supportedProcessors = WebProcessingExtensions.GetBySupportedCommands(processors, commands).ToArray();
+            IImageWebProcessor[] supportedProcessors = processors.GetBySupportedCommands(commands).ToArray();
 
             Assert.Empty(supportedProcessors);
         }