Add tests

Author: JimBobSquarePants

src/ImageSharp.Web/Commands/CommandCollection.cs

@@ -48,7 +48,7 @@ private CommandCollection(IEqualityComparer<string> comparer)
             {
                 if (this.TryGetValue(key, out KeyValuePair<string, string> item))
                 {
-                    return item.Key;
+                    return item.Value;
                 }
 
                 throw new KeyNotFoundException();

tests/ImageSharp.Web.Tests/Commands/CommandCollectionTests.cs

@@ -0,0 +1,86 @@
+// Copyright (c) Six Labors.
+// Licensed under the Apache License, Version 2.0.
+
+using System.Collections.Generic;
+using SixLabors.ImageSharp.Web.Commands;
+using Xunit;
+
+namespace SixLabors.ImageSharp.Web.Tests.Commands
+{
+    public class CommandCollectionTests
+    {
+        [Fact]
+        public void CanAddCommands()
+        {
+            CommandCollection collection = new();
+            collection.Add(new("a", "b"));
+            Assert.Single(collection);
+        }
+
+        [Fact]
+        public void CanReadCommands()
+        {
+            const string key = "a";
+            const string value = "b";
+            CommandCollection collection = new();
+            collection.Add(new(key, value));
+
+            Assert.Equal(value, collection[key]);
+        }
+
+        [Fact]
+        public void CanInsertCommands()
+        {
+            KeyValuePair<string, string> kv1 = new("a", "b");
+            KeyValuePair<string, string> kv2 = new("c", "d");
+
+            CommandCollection collection = new();
+            collection.Add(kv1);
+            Assert.Single(collection);
+
+            collection.Insert(0, kv2);
+            Assert.Equal(2, collection.Count);
+
+            Assert.Equal(kv1.Value, collection[kv1.Key]);
+            Assert.Equal(kv2.Value, collection[kv2.Key]);
+
+            Assert.Equal(1, collection.IndexOf(kv1));
+            Assert.Equal(0, collection.IndexOf(kv2));
+        }
+
+        [Fact]
+        public void CanRemoveCommands()
+        {
+            KeyValuePair<string, string> kv1 = new("a", "b");
+            KeyValuePair<string, string> kv2 = new("c", "d");
+            CommandCollection collection = new();
+
+            collection.Add(kv1);
+            collection.Add(kv2);
+
+            Assert.Equal(2, collection.Count);
+
+            collection.Remove(kv1);
+
+            Assert.Single(collection);
+            Assert.Equal(kv2.Value, collection[kv2.Key]);
+        }
+
+        [Fact]
+        public void CanClearCommands()
+        {
+            KeyValuePair<string, string> kv1 = new("a", "b");
+            KeyValuePair<string, string> kv2 = new("c", "d");
+            CommandCollection collection = new();
+
+            collection.Add(kv1);
+            collection.Add(kv2);
+
+            Assert.Equal(2, collection.Count);
+
+            collection.Clear();
+
+            Assert.Empty(collection);
+        }
+    }
+}