From a2aedd19bb1d159137fc6aa864428b57fedce99d Mon Sep 17 00:00:00 2001
From: Krzysztof Jafra <falwickster@gmail.com>
Date: Wed, 13 Jun 2018 12:07:19 +0200
Subject: [PATCH 1/4] New ICollection<T> extension method - Swap

---
 .../ICollection[T].Swap.cs                    | 42 +++++++++++++++++++
 src/Z.Collections/Z.Collections.csproj        |  2 +
 .../ICollection[T].Swap.cs                    | 38 +++++++++++++++++
 .../Z.Collections.Test.csproj                 |  1 +
 4 files changed, 83 insertions(+)
 create mode 100644 src/Z.Collections/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs
 create mode 100644 test/Z.Collections.Test/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs

diff --git a/src/Z.Collections/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs b/src/Z.Collections/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs
new file mode 100644
index 00000000..53c4df1d
--- /dev/null
+++ b/src/Z.Collections/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs
@@ -0,0 +1,42 @@
+// Description: C# Extension Methods Library to enhances the .NET Framework by adding hundreds of new methods. It drastically increases developers productivity and code readability. Support C# and VB.NET
+// Website & Documentation: https://github.com/zzzprojects/Z.ExtensionMethods
+// Forum: https://github.com/zzzprojects/Z.ExtensionMethods/issues
+// License: https://github.com/zzzprojects/Z.ExtensionMethods/blob/master/LICENSE
+// More projects: http://www.zzzprojects.com/
+// Copyright © ZZZ Projects Inc. 2014 - 2016. All rights reserved.
+using System;
+using System.Collections.Generic;
+
+public static partial class Extensions
+{
+    /// <summary>
+    /// An ICollection&lt;T&gt; extension method that swaps value only when it exists in a collection.
+    /// </summary>
+    /// <typeparam name="T">Generic type parameter.</typeparam>
+    /// <param name="this">The @this to act on.</param>
+    /// <param name="oldValue">The old value.</param>
+    /// <param name="newValue">The new value.</param>
+    /// <returns>
+    /// true if it succeeds, false if it fails.
+    /// </returns>
+    public static ICollection<T> Swap<T>(this ICollection<T> @this, T oldValue, T newValue)
+    {
+        var collectionAsList = @this as IList<T>;
+
+        if (collectionAsList != null)
+        {
+            var oldIndex = collectionAsList.IndexOf(oldValue);
+
+            if(oldIndex < 0)
+                return collectionAsList;
+
+            collectionAsList.RemoveAt(oldIndex);
+            collectionAsList.Insert(oldIndex, newValue);
+            return collectionAsList;
+        }
+
+        @this.Remove(oldValue);
+        @this.Add(newValue);
+        return @this;
+    }
+}
\ No newline at end of file
diff --git a/src/Z.Collections/Z.Collections.csproj b/src/Z.Collections/Z.Collections.csproj
index da9e6830..39881676 100644
--- a/src/Z.Collections/Z.Collections.csproj
+++ b/src/Z.Collections/Z.Collections.csproj
@@ -63,6 +63,7 @@
   </ItemGroup>
   <ItemGroup>
     <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="System.Collections.Generic.ICollection[T]\ICollection[T].Swap.cs" />
     <Compile Include="System.Collections.Generic.ICollection[T]\ICollection[T].AddIf.cs" />
     <Compile Include="System.Collections.Generic.ICollection[T]\ICollection[T].AddIfNotContains.cs" />
     <Compile Include="System.Collections.Generic.ICollection[T]\ICollection[T].AddRange.cs" />
@@ -102,6 +103,7 @@
     <Compile Include="System.Collections.IDictionary\IDictionary.ToHashtable.cs" />
     <Compile Include="System.Collections.Specialized.NameValueCollection\NameValueCollection.ToDictionary.cs" />
   </ItemGroup>
+  <ItemGroup />
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
        Other similar extension points exist, see Microsoft.Common.targets.
diff --git a/test/Z.Collections.Test/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs b/test/Z.Collections.Test/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs
new file mode 100644
index 00000000..2406a5b4
--- /dev/null
+++ b/test/Z.Collections.Test/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs
@@ -0,0 +1,38 @@
+// Description: C# Extension Methods Library to enhances the .NET Framework by adding hundreds of new methods. It drastically increases developers productivity and code readability. Support C# and VB.NET
+// Website & Documentation: https://github.com/zzzprojects/Z.ExtensionMethods
+// Forum: https://github.com/zzzprojects/Z.ExtensionMethods/issues
+// License: https://github.com/zzzprojects/Z.ExtensionMethods/blob/master/LICENSE
+// More projects: http://www.zzzprojects.com/
+// Copyright © ZZZ Projects Inc. 2014 - 2016. All rights reserved.
+using System.Collections.Generic;
+using System.Linq;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace Z.Collections.Test
+{
+    [TestClass]
+    public class System_Collections_Generic_ICollection_T_Swap
+    {
+        [TestMethod]
+        public void Swap()
+        {
+            // Type
+            var stringList = new List<string>();
+            stringList.AddRange("Foo", "Bar", "Baz");
+
+            // Examples
+            var example1 = new List<string>(stringList).Swap("Baz", "NewBaz");
+            var example2 = new List<string>(stringList).Swap("NoValueFound", "NoBaz");
+
+            // Expected results
+            var result1 = new List<string>() {"Foo", "Bar", "NewBaz"};
+            var result2 = new List<string>(stringList);
+
+            // Unit Test
+            Assert.IsTrue(example1.Contains("NewBaz"), "The collection should contain this value");
+            Assert.IsFalse(example2.Contains("NoBaz"), "The collection shouldn't contain this value");
+            Assert.IsTrue(example1.SequenceEqual(result1), "The collection should have the replaced value");
+            Assert.IsTrue(example2.SequenceEqual(result2), "The collection shouldn't have the replaced value");
+        }
+    }
+}
\ No newline at end of file
diff --git a/test/Z.Collections.Test/Z.Collections.Test.csproj b/test/Z.Collections.Test/Z.Collections.Test.csproj
index 76c55930..e4ab4290 100644
--- a/test/Z.Collections.Test/Z.Collections.Test.csproj
+++ b/test/Z.Collections.Test/Z.Collections.Test.csproj
@@ -78,6 +78,7 @@
     <Compile Include="System.Collections.Generic.ICollection[T]\ICollection[T].RemoveRangeIf.cs" />
     <Compile Include="System.Collections.Generic.ICollection[T]\ICollection[T].RemoveRangeIfContains.cs" />
     <Compile Include="System.Collections.Generic.ICollection[T]\ICollection[T].RemoveWhere.cs" />
+    <Compile Include="System.Collections.Generic.ICollection[T]\ICollection[T].Swap.cs" />
     <Compile Include="System.Collections.Generic.IDictionary[string, object]\IDictionary[string, object].ToExpando.cs" />
     <Compile Include="System.Collections.Generic.IDictionary[string, string]\IDictionary[string, string].ToNameValueCollection.cs" />
     <Compile Include="System.Collections.Generic.IDictionary[TKey,TValue]\IDictionary[TKey,TValue].AddIfNotContainsKey.cs" />

From 2568c12b21d1fa64641f726291d6d7c6ef31b151 Mon Sep 17 00:00:00 2001
From: Krzysztof Jafra <falwickster@gmail.com>
Date: Wed, 13 Jun 2018 13:34:01 +0200
Subject: [PATCH 2/4] ICollection<T>.Swap method changed to void

---
 .../ICollection[T].Swap.cs                    | 21 ++++---------------
 .../ICollection[T].Swap.cs                    | 10 +++++++--
 2 files changed, 12 insertions(+), 19 deletions(-)

diff --git a/src/Z.Collections/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs b/src/Z.Collections/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs
index 53c4df1d..f7f3facd 100644
--- a/src/Z.Collections/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs
+++ b/src/Z.Collections/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs
@@ -4,7 +4,6 @@
 // License: https://github.com/zzzprojects/Z.ExtensionMethods/blob/master/LICENSE
 // More projects: http://www.zzzprojects.com/
 // Copyright © ZZZ Projects Inc. 2014 - 2016. All rights reserved.
-using System;
 using System.Collections.Generic;
 
 public static partial class Extensions
@@ -19,24 +18,12 @@ public static partial class Extensions
     /// <returns>
     /// true if it succeeds, false if it fails.
     /// </returns>
-    public static ICollection<T> Swap<T>(this ICollection<T> @this, T oldValue, T newValue)
+    public static void Swap<T>(this ICollection<T> @this, T oldValue, T newValue)
     {
-        var collectionAsList = @this as IList<T>;
-
-        if (collectionAsList != null)
+        if (@this.Contains(oldValue))
         {
-            var oldIndex = collectionAsList.IndexOf(oldValue);
-
-            if(oldIndex < 0)
-                return collectionAsList;
-
-            collectionAsList.RemoveAt(oldIndex);
-            collectionAsList.Insert(oldIndex, newValue);
-            return collectionAsList;
+            @this.Remove(oldValue);
+            @this.Add(newValue);
         }
-
-        @this.Remove(oldValue);
-        @this.Add(newValue);
-        return @this;
     }
 }
\ No newline at end of file
diff --git a/test/Z.Collections.Test/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs b/test/Z.Collections.Test/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs
index 2406a5b4..e9accc3a 100644
--- a/test/Z.Collections.Test/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs
+++ b/test/Z.Collections.Test/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs
@@ -21,18 +21,24 @@ public void Swap()
             stringList.AddRange("Foo", "Bar", "Baz");
 
             // Examples
-            var example1 = new List<string>(stringList).Swap("Baz", "NewBaz");
-            var example2 = new List<string>(stringList).Swap("NoValueFound", "NoBaz");
+            var example1 = new List<string>(stringList);
+            example1.Swap("Baz", "NewBaz");
+            var example2 = new List<string>(stringList);
+            example2.Swap("NoValueFound", "NoBaz");
+            var example3 = new List<string>(stringList);
+            example3.Swap(null, "NothingChanged");
 
             // Expected results
             var result1 = new List<string>() {"Foo", "Bar", "NewBaz"};
             var result2 = new List<string>(stringList);
+            var result3 = new List<string>(stringList);
 
             // Unit Test
             Assert.IsTrue(example1.Contains("NewBaz"), "The collection should contain this value");
             Assert.IsFalse(example2.Contains("NoBaz"), "The collection shouldn't contain this value");
             Assert.IsTrue(example1.SequenceEqual(result1), "The collection should have the replaced value");
             Assert.IsTrue(example2.SequenceEqual(result2), "The collection shouldn't have the replaced value");
+            Assert.IsTrue(example3.SequenceEqual(result3), "The collection shouldn't have the replaced value");
         }
     }
 }
\ No newline at end of file

From f7969ed318ffa6543c4f1bff65fb932daef91001 Mon Sep 17 00:00:00 2001
From: Krzysztof Jafra <falwickster@gmail.com>
Date: Wed, 13 Jun 2018 14:33:24 +0200
Subject: [PATCH 3/4] ICollection<T> Swap replaced to IList<T> Swap

---
 .../IList[T].Swap.cs                          | 32 +++++++++++++++++++
 src/Z.Collections/Z.Collections.csproj        |  2 +-
 .../IList[T].Swap.cs}                         |  6 +++-
 .../Z.Collections.Test.csproj                 |  2 +-
 4 files changed, 39 insertions(+), 3 deletions(-)
 create mode 100644 src/Z.Collections/System.Collections.Generic.IList[T]/IList[T].Swap.cs
 rename test/Z.Collections.Test/{System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs => System.Collections.Generic.IList[T]/IList[T].Swap.cs} (86%)

diff --git a/src/Z.Collections/System.Collections.Generic.IList[T]/IList[T].Swap.cs b/src/Z.Collections/System.Collections.Generic.IList[T]/IList[T].Swap.cs
new file mode 100644
index 00000000..afd14092
--- /dev/null
+++ b/src/Z.Collections/System.Collections.Generic.IList[T]/IList[T].Swap.cs
@@ -0,0 +1,32 @@
+// Description: C# Extension Methods Library to enhances the .NET Framework by adding hundreds of new methods. It drastically increases developers productivity and code readability. Support C# and VB.NET
+// Website & Documentation: https://github.com/zzzprojects/Z.ExtensionMethods
+// Forum: https://github.com/zzzprojects/Z.ExtensionMethods/issues
+// License: https://github.com/zzzprojects/Z.ExtensionMethods/blob/master/LICENSE
+// More projects: http://www.zzzprojects.com/
+// Copyright © ZZZ Projects Inc. 2014 - 2016. All rights reserved.
+
+using System.Collections.Generic;
+
+public static partial class Extensions
+{
+    /// <summary>
+    /// An ICollection&lt;T&gt; extension method that swaps item only when it exists in a collection.
+    /// </summary>
+    /// <typeparam name="T">Generic type parameter.</typeparam>
+    /// <param name="this">The @this to act on.</param>
+    /// <param name="oldValue">The old value.</param>
+    /// <param name="newValue">The new value.</param>
+    /// <returns>
+    /// true if it succeeds, false if it fails.
+    /// </returns>
+    public static void Swap<T>(this IList<T> @this, T oldValue, T newValue)
+    {
+            var oldIndex = @this.IndexOf(oldValue);
+
+            if (oldIndex < 0)
+                return;
+
+            @this.RemoveAt(oldIndex);
+            @this.Insert(oldIndex, newValue);
+    }
+}
\ No newline at end of file
diff --git a/src/Z.Collections/Z.Collections.csproj b/src/Z.Collections/Z.Collections.csproj
index 39881676..ccd0c9d0 100644
--- a/src/Z.Collections/Z.Collections.csproj
+++ b/src/Z.Collections/Z.Collections.csproj
@@ -63,7 +63,7 @@
   </ItemGroup>
   <ItemGroup>
     <Compile Include="Properties\AssemblyInfo.cs" />
-    <Compile Include="System.Collections.Generic.ICollection[T]\ICollection[T].Swap.cs" />
+    <Compile Include="System.Collections.Generic.IList[T]\IList[T].Swap.cs" />
     <Compile Include="System.Collections.Generic.ICollection[T]\ICollection[T].AddIf.cs" />
     <Compile Include="System.Collections.Generic.ICollection[T]\ICollection[T].AddIfNotContains.cs" />
     <Compile Include="System.Collections.Generic.ICollection[T]\ICollection[T].AddRange.cs" />
diff --git a/test/Z.Collections.Test/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs b/test/Z.Collections.Test/System.Collections.Generic.IList[T]/IList[T].Swap.cs
similarity index 86%
rename from test/Z.Collections.Test/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs
rename to test/Z.Collections.Test/System.Collections.Generic.IList[T]/IList[T].Swap.cs
index e9accc3a..97f4c082 100644
--- a/test/Z.Collections.Test/System.Collections.Generic.ICollection[T]/ICollection[T].Swap.cs
+++ b/test/Z.Collections.Test/System.Collections.Generic.IList[T]/IList[T].Swap.cs
@@ -11,7 +11,7 @@
 namespace Z.Collections.Test
 {
     [TestClass]
-    public class System_Collections_Generic_ICollection_T_Swap
+    public class System_Collections_Generic_IList_T_Swap
     {
         [TestMethod]
         public void Swap()
@@ -27,11 +27,14 @@ public void Swap()
             example2.Swap("NoValueFound", "NoBaz");
             var example3 = new List<string>(stringList);
             example3.Swap(null, "NothingChanged");
+            var example4 = new List<string>(stringList);
+            example4.Swap("Bar", "NewBar");
 
             // Expected results
             var result1 = new List<string>() {"Foo", "Bar", "NewBaz"};
             var result2 = new List<string>(stringList);
             var result3 = new List<string>(stringList);
+            var result4 = example4.ElementAt(1).Equals("NewBar");
 
             // Unit Test
             Assert.IsTrue(example1.Contains("NewBaz"), "The collection should contain this value");
@@ -39,6 +42,7 @@ public void Swap()
             Assert.IsTrue(example1.SequenceEqual(result1), "The collection should have the replaced value");
             Assert.IsTrue(example2.SequenceEqual(result2), "The collection shouldn't have the replaced value");
             Assert.IsTrue(example3.SequenceEqual(result3), "The collection shouldn't have the replaced value");
+            Assert.IsTrue(result4, "The item in a collection shouldn't change it's position");
         }
     }
 }
\ No newline at end of file
diff --git a/test/Z.Collections.Test/Z.Collections.Test.csproj b/test/Z.Collections.Test/Z.Collections.Test.csproj
index e4ab4290..5cdf1ca3 100644
--- a/test/Z.Collections.Test/Z.Collections.Test.csproj
+++ b/test/Z.Collections.Test/Z.Collections.Test.csproj
@@ -78,7 +78,7 @@
     <Compile Include="System.Collections.Generic.ICollection[T]\ICollection[T].RemoveRangeIf.cs" />
     <Compile Include="System.Collections.Generic.ICollection[T]\ICollection[T].RemoveRangeIfContains.cs" />
     <Compile Include="System.Collections.Generic.ICollection[T]\ICollection[T].RemoveWhere.cs" />
-    <Compile Include="System.Collections.Generic.ICollection[T]\ICollection[T].Swap.cs" />
+    <Compile Include="System.Collections.Generic.IList[T]\IList[T].Swap.cs" />
     <Compile Include="System.Collections.Generic.IDictionary[string, object]\IDictionary[string, object].ToExpando.cs" />
     <Compile Include="System.Collections.Generic.IDictionary[string, string]\IDictionary[string, string].ToNameValueCollection.cs" />
     <Compile Include="System.Collections.Generic.IDictionary[TKey,TValue]\IDictionary[TKey,TValue].AddIfNotContainsKey.cs" />

From 78ed0dfece23cf7a79f3264f3156b5c57592e69f Mon Sep 17 00:00:00 2001
From: Krzysztof Jafra <falwickster@gmail.com>
Date: Thu, 14 Jun 2018 09:07:05 +0200
Subject: [PATCH 4/4] Fixed method to swap multiple same values in a list

---
 .../IList[T].Swap.cs                          | 10 ++++-----
 .../IList[T].Swap.cs                          | 22 ++++++++++++++-----
 2 files changed, 22 insertions(+), 10 deletions(-)

diff --git a/src/Z.Collections/System.Collections.Generic.IList[T]/IList[T].Swap.cs b/src/Z.Collections/System.Collections.Generic.IList[T]/IList[T].Swap.cs
index afd14092..0cd404ba 100644
--- a/src/Z.Collections/System.Collections.Generic.IList[T]/IList[T].Swap.cs
+++ b/src/Z.Collections/System.Collections.Generic.IList[T]/IList[T].Swap.cs
@@ -21,12 +21,12 @@ public static partial class Extensions
     /// </returns>
     public static void Swap<T>(this IList<T> @this, T oldValue, T newValue)
     {
-            var oldIndex = @this.IndexOf(oldValue);
-
-            if (oldIndex < 0)
-                return;
-
+        var oldIndex = @this.IndexOf(oldValue);
+        while (oldIndex > 0)
+        {
             @this.RemoveAt(oldIndex);
             @this.Insert(oldIndex, newValue);
+            oldIndex = @this.IndexOf(oldValue);
+        }
     }
 }
\ No newline at end of file
diff --git a/test/Z.Collections.Test/System.Collections.Generic.IList[T]/IList[T].Swap.cs b/test/Z.Collections.Test/System.Collections.Generic.IList[T]/IList[T].Swap.cs
index 97f4c082..ab2c37bd 100644
--- a/test/Z.Collections.Test/System.Collections.Generic.IList[T]/IList[T].Swap.cs
+++ b/test/Z.Collections.Test/System.Collections.Generic.IList[T]/IList[T].Swap.cs
@@ -17,24 +17,34 @@ public class System_Collections_Generic_IList_T_Swap
         public void Swap()
         {
             // Type
-            var stringList = new List<string>();
-            stringList.AddRange("Foo", "Bar", "Baz");
+            var stringList = new List<string>() { "Foo", "Bar", "Baz" };
+            var obj1 = new { Id = 1, Message = "Foo" };
+            var obj2 = new { Id= 2, Message = "Bar" };
+            var obj3 = new { Id = 3, Message = "Baz" };
 
             // Examples
             var example1 = new List<string>(stringList);
-            example1.Swap("Baz", "NewBaz");
             var example2 = new List<string>(stringList);
-            example2.Swap("NoValueFound", "NoBaz");
             var example3 = new List<string>(stringList);
-            example3.Swap(null, "NothingChanged");
             var example4 = new List<string>(stringList);
+            var example5 = new List<string>() {"Foo", "Bar", "Bar"};
+            var example6 = new List<object>() { obj1, obj2 };
+
+            //Swaps
+            example1.Swap("Baz", "NewBaz");
+            example2.Swap("NoValueFound", "NoBaz");
+            example3.Swap(null, "NothingChanged");
             example4.Swap("Bar", "NewBar");
+            example5.Swap("Bar", "Baz");
+            example6.Swap(obj2, obj3);
 
             // Expected results
             var result1 = new List<string>() {"Foo", "Bar", "NewBaz"};
             var result2 = new List<string>(stringList);
             var result3 = new List<string>(stringList);
             var result4 = example4.ElementAt(1).Equals("NewBar");
+            var result5 = example5.Contains("Bar");
+            var result6 = example6.Contains(obj3);
 
             // Unit Test
             Assert.IsTrue(example1.Contains("NewBaz"), "The collection should contain this value");
@@ -43,6 +53,8 @@ public void Swap()
             Assert.IsTrue(example2.SequenceEqual(result2), "The collection shouldn't have the replaced value");
             Assert.IsTrue(example3.SequenceEqual(result3), "The collection shouldn't have the replaced value");
             Assert.IsTrue(result4, "The item in a collection shouldn't change it's position");
+            Assert.IsFalse(result5, "All values should be swaped");
+            Assert.IsTrue(result6, "The object in a collection should be swaped");
         }
     }
 }
\ No newline at end of file