Add the SequenceEqual extension

ShittyLINQ/SequenceEqual.cs

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+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace ShittyLINQ
+{
+    public static partial class Extensions
+    {
+        public static bool SequenceEqual<T>(this IEnumerable<T> first, IEnumerable<T> second)
+        {
+            if (first.Count() != second.Count())
+                return false;
+
+            var areSequenceEquals = true;
+
+            for (int i = 0; i < first.Count(); i++)
+            {
+                areSequenceEquals &= (first.ElementAt(i).Equals(second.ElementAt(i)));
+            }
+
+            return areSequenceEquals;
+        }
+
+        public static bool SequenceEqual<T>(
+            this IEnumerable<T> first, 
+            IEnumerable<T> second,
+            IEqualityComparer<T> comparer)
+        {
+            if (first.Count() != second.Count())
+                return false;
+
+            var areSequenceEquals = true;
+
+            for (int i = 0; i < first.Count(); i++)
+            {
+                areSequenceEquals &= (comparer.Equals(first.ElementAt(i), second.ElementAt(i)));
+            }
+
+            return areSequenceEquals;
+        }
+    }
+}

ShittyLinqTests/SequenceEqualTests.cs

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+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using ShittyLINQ;
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace ShittyTests
+{
+    class Pet
+    {
+        public string Name { get; set; }
+        public int Age { get; set; }
+    }
+
+    class ProductA
+    {
+        public string Name { get; set; }
+        public int Code { get; set; }
+    }
+
+    class ProductComparer : IEqualityComparer<ProductA>
+    {
+
+        public bool Equals(ProductA x, ProductA y)
+        { 
+            if (ReferenceEquals(x, y)) return true;
+
+            return x != null && y != null && x.Code.Equals(y.Code) && x.Name.Equals(y.Name);
+        }
+
+        public int GetHashCode(ProductA obj)
+        {
+            int hashProductName = obj.Name == null ? 0 : obj.Name.GetHashCode();
+
+            int hashProductCode = obj.Code.GetHashCode();
+
+            return hashProductName ^ hashProductCode;
+        }
+    }
+
+    /// <summary>
+    /// The code for the tests is the same than in the Microsoft example
+    /// for the SequenceEqual extension
+    /// </summary>
+    [TestClass]
+    public class SequenceEqualTests
+    {
+        [TestMethod]
+        public void When_Two_List_Are_Fill_With_Same_Objects_Then_Should_Be_Equals()
+        {
+            var pet1 = new Pet { Name = "Turbo", Age = 2 };
+            var pet2 = new Pet { Name = "Peanut", Age = 8 };
+
+            var pets1 = new List<Pet> { pet1, pet2 };
+            var pets2 = new List<Pet> { pet1, pet2 };
+
+            var equal = pets1.SequenceEqual(pets2);
+
+            Assert.IsTrue(equal);
+        }
+
+        [TestMethod]
+        public void When_Two_List_Are_Fill_With_Same_Objects_But_Different_References_Then_Should_Be_Not_Equals()
+        {
+            var pet1 = new Pet() { Name = "Turbo", Age = 2 };
+            var pet2 = new Pet() { Name = "Peanut", Age = 8 };
+
+            // Create two lists of pets.
+            var pets1 = new List<Pet> { pet1, pet2 };
+            var pets2 =
+                new List<Pet> { new Pet { Name = "Turbo", Age = 2 },
+                        new Pet { Name = "Peanut", Age = 8 } };
+
+            var equal = pets1.SequenceEqual(pets2);
+
+            Assert.IsFalse(equal);
+        }
+
+        [TestMethod]
+        public void When_Two_Lists_Are_Fill_With_Different_References_But_With_Comparer_Then_Should_Be_Equals()
+        {
+            ProductA[] storeA = { new ProductA { Name = "apple", Code = 9 },
+                       new ProductA { Name = "orange", Code = 4 } };
+
+            ProductA[] storeB = { new ProductA { Name = "apple", Code = 9 },
+                       new ProductA { Name = "orange", Code = 4 } };
+
+            bool equalAB = storeA.SequenceEqual(storeB, new ProductComparer());
+
+            Assert.IsTrue(equalAB);
+        }
+    }
+}