Revert "Revert "Add another Zip IEnumerable<T> extension method (#26582)""

src/System.Linq.Queryable/ref/System.Linq.Queryable.cs

@@ -163,6 +163,7 @@ public static partial class Queryable
         public static System.Linq.IQueryable<TSource> Union<TSource>(this System.Linq.IQueryable<TSource> source1, System.Collections.Generic.IEnumerable<TSource> source2, System.Collections.Generic.IEqualityComparer<TSource> comparer) { throw null; }
         public static System.Linq.IQueryable<TSource> Where<TSource>(this System.Linq.IQueryable<TSource> source, System.Linq.Expressions.Expression<System.Func<TSource, bool>> predicate) { throw null; }
         public static System.Linq.IQueryable<TSource> Where<TSource>(this System.Linq.IQueryable<TSource> source, System.Linq.Expressions.Expression<System.Func<TSource, int, bool>> predicate) { throw null; }
+        public static System.Linq.IQueryable<(TFirst First, TSecond Second)> Zip<TFirst, TSecond>(this System.Linq.IQueryable<TFirst> source1, System.Collections.Generic.IEnumerable<TSecond> source2) { throw null; }
         public static System.Linq.IQueryable<TResult> Zip<TFirst, TSecond, TResult>(this System.Linq.IQueryable<TFirst> source1, System.Collections.Generic.IEnumerable<TSecond> source2, System.Linq.Expressions.Expression<System.Func<TFirst, TSecond, TResult>> resultSelector) { throw null; }
     }
 }

src/System.Linq.Queryable/src/System/Linq/CachedReflection.cs

@@ -830,6 +830,13 @@ public static MethodInfo Where_Index_TSource_2(Type TSource) =>
              (s_Where_Index_TSource_2 = new Func<IQueryable<object>, Expression<Func<object, int, bool>>, IQueryable<object>>(Queryable.Where).GetMethodInfo().GetGenericMethodDefinition()))
               .MakeGenericMethod(TSource);
 
+        private static MethodInfo s_Zip_TFirst_TSecond_2;
+
+        public static MethodInfo Zip_TFirst_TSecond_2(Type TFirst, Type TSecond) =>
+            (s_Zip_TFirst_TSecond_2 ??
+            (s_Zip_TFirst_TSecond_2 = new Func<IQueryable<object>, IEnumerable<object>, IQueryable<ValueTuple<object, object>>>(Queryable.Zip).GetMethodInfo().GetGenericMethodDefinition()))
+            .MakeGenericMethod(TFirst, TSecond);
+
         private static MethodInfo s_Zip_TFirst_TSecond_TResult_3;
 
         public static MethodInfo Zip_TFirst_TSecond_TResult_3(Type TFirst, Type TSecond, Type TResult) =>
@@ -866,4 +873,4 @@ public static MethodInfo Prepend_TSource_2(Type TSource) =>
              (s_Prepend_TSource_2 = new Func<IQueryable<object>, object, IQueryable<object>>(Queryable.Prepend).GetMethodInfo().GetGenericMethodDefinition()))
               .MakeGenericMethod(TSource);
     }
-}
+}

src/System.Linq.Queryable/src/System/Linq/Queryable.cs

@@ -592,6 +592,25 @@ public static IQueryable<TSource> Concat<TSource>(this IQueryable<TSource> sourc
                     ));
         }
 
+        public static IQueryable<(TFirst First, TSecond Second)> Zip<TFirst, TSecond>(this IQueryable<TFirst> source1, IEnumerable<TSecond> source2)
+        {
+            if (source1 == null)
+            {
+                throw Error.ArgumentNull(nameof(source1));
+            }
+
+            if (source2 == null)
+            {
+                throw Error.ArgumentNull(nameof(source2));
+            }
+
+            return source1.Provider.CreateQuery<(TFirst, TSecond)>(
+                Expression.Call(
+                    null,
+                    CachedReflectionInfo.Zip_TFirst_TSecond_2(typeof(TFirst), typeof(TSecond)),
+                    source1.Expression, GetSourceExpression(source2)));
+        }
+
         public static IQueryable<TResult> Zip<TFirst, TSecond, TResult>(this IQueryable<TFirst> source1, IEnumerable<TSecond> source2, Expression<Func<TFirst, TSecond, TResult>> resultSelector)
         {
             if (source1 == null)

src/System.Linq.Queryable/tests/System.Linq.Queryable.Tests.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <ProjectGuid>{7B88D79B-B799-4116-A7D0-AED572540CD4}</ProjectGuid>
     <Configurations>netcoreapp-Debug;netcoreapp-Release;netstandard-Debug;netstandard-Release</Configurations>
@@ -7,6 +7,7 @@
     <Compile Include="AppendPrependTests.cs" />
     <Compile Include="TakeLastTests.cs" />
     <Compile Include="SkipLastTests.cs" />
+    <Compile Include="ZipTests.netcoreapp.cs" />
   </ItemGroup>
   <ItemGroup>
     <Compile Include="AggregateTests.cs" />

src/System.Linq.Queryable/tests/ZipTests.cs

@@ -7,7 +7,7 @@
 
 namespace System.Linq.Tests
 {
-    public class ZipTests : EnumerableBasedTests
+    public partial class ZipTests : EnumerableBasedTests
     {
         [Fact]
         public void CorrectResults()

src/System.Linq.Queryable/tests/ZipTests.netcoreapp.cs

@@ -0,0 +1,53 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using Xunit;
+
+namespace System.Linq.Tests
+{
+    public partial class ZipTests
+    {
+        [Fact]
+        public void Zip2_CorrectResults()
+        {
+            int[] first = new int[] { 1, 2, 3 };
+            int[] second = new int[] { 2, 5, 9 };
+            var expected = new (int, int)[] { (1, 2), (2, 5), (3, 9) };
+            Assert.Equal(expected, first.AsQueryable().Zip(second.AsQueryable()));
+        }
+
+        [Fact]
+        public void Zip2_FirstIsNull()
+        {
+            IQueryable<int> first = null;
+            int[] second = new int[] { 2, 5, 9 };
+            AssertExtensions.Throws<ArgumentNullException>("source1", () => first.Zip(second.AsQueryable()));
+        }
+
+        [Fact]
+        public void Zip2_SecondIsNull()
+        {
+            int[] first = new int[] { 1, 2, 3 };
+            IQueryable<int> second = null;
+            AssertExtensions.Throws<ArgumentNullException>("source2", () => first.AsQueryable().Zip(second));
+        }
+
+        [Fact]
+        public void Zip2()
+        {
+            int count = (new int[] { 0, 1, 2 }).AsQueryable().Zip((new int[] { 10, 11, 12 }).AsQueryable()).Count();
+            Assert.Equal(3, count);
+        }
+
+        [Fact]
+        public void TupleNames()
+        {
+            int[] first = new int[] { 1 };
+            int[] second = new int[] { 2 };
+            var tuple = first.AsQueryable().Zip(second.AsQueryable()).First();
+            Assert.Equal(tuple.Item1, tuple.First);
+            Assert.Equal(tuple.Item2, tuple.Second);
+        }
+    }
+}

src/System.Linq/ref/System.Linq.cs

@@ -190,6 +190,7 @@ public static partial class Enumerable
         public static System.Collections.Generic.IEnumerable<TSource> Union<TSource>(this System.Collections.Generic.IEnumerable<TSource> first, System.Collections.Generic.IEnumerable<TSource> second, System.Collections.Generic.IEqualityComparer<TSource> comparer) { throw null; }
         public static System.Collections.Generic.IEnumerable<TSource> Where<TSource>(this System.Collections.Generic.IEnumerable<TSource> source, System.Func<TSource, bool> predicate) { throw null; }
         public static System.Collections.Generic.IEnumerable<TSource> Where<TSource>(this System.Collections.Generic.IEnumerable<TSource> source, System.Func<TSource, int, bool> predicate) { throw null; }
+        public static System.Collections.Generic.IEnumerable<(TFirst First,TSecond Second)> Zip<TFirst, TSecond>(this System.Collections.Generic.IEnumerable<TFirst> first, System.Collections.Generic.IEnumerable<TSecond> second) { throw null; }
         public static System.Collections.Generic.IEnumerable<TResult> Zip<TFirst, TSecond, TResult>(this System.Collections.Generic.IEnumerable<TFirst> first, System.Collections.Generic.IEnumerable<TSecond> second, System.Func<TFirst, TSecond, TResult> resultSelector) { throw null; }
     }
     public partial interface IGrouping<out TKey, out TElement> : System.Collections.Generic.IEnumerable<TElement>, System.Collections.IEnumerable

src/System.Linq/src/System/Linq/Zip.cs

@@ -28,6 +28,33 @@ public static IEnumerable<TResult> Zip<TFirst, TSecond, TResult>(this IEnumerabl
             return ZipIterator(first, second, resultSelector);
         }
 
+        public static IEnumerable<(TFirst First, TSecond Second)> Zip<TFirst, TSecond>(this IEnumerable<TFirst> first, IEnumerable<TSecond> second)
+        {
+            if (first is null)
+            {
+                ThrowHelper.ThrowArgumentNullException(ExceptionArgument.first);
+            }
+
+            if (second is null)
+            {
+                ThrowHelper.ThrowArgumentNullException(ExceptionArgument.second);
+            }
+
+            return ZipIterator(first, second);
+        }
+
+        private static IEnumerable<(TFirst, TSecond)> ZipIterator<TFirst, TSecond>(IEnumerable<TFirst> first, IEnumerable<TSecond> second)
+        {
+            using (IEnumerator<TFirst> e1 = first.GetEnumerator())
+            using (IEnumerator<TSecond> e2 = second.GetEnumerator())
+            {
+                while (e1.MoveNext() && e2.MoveNext())
+                {
+                    yield return (e1.Current, e2.Current);
+                }
+            }
+        }
+
         private static IEnumerable<TResult> ZipIterator<TFirst, TSecond, TResult>(IEnumerable<TFirst> first, IEnumerable<TSecond> second, Func<TFirst, TSecond, TResult> resultSelector)
         {
             using (IEnumerator<TFirst> e1 = first.GetEnumerator())

src/System.Linq/tests/System.Linq.Tests.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <ProjectGuid>{7C70BB15-870B-4946-8098-625DACD645A6}</ProjectGuid>
     <Configurations>netcoreapp-Debug;netcoreapp-Release;netstandard-Debug;netstandard-Release;uapaot-Debug;uapaot-Release</Configurations>
@@ -10,6 +10,7 @@
     <Compile Include="OrderByTests.cs" />
     <Compile Include="ToHashSetTests.cs" />
     <Compile Include="SelectManyTests.netcoreapp.cs" />
+    <Compile Include="ZipTests.netcoreapp.cs" />
   </ItemGroup>
   <ItemGroup>
     <Compile Include="AggregateTests.cs" />

src/System.Linq/tests/ZipTests.cs

@@ -2,14 +2,12 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using System;
-using System.Collections;
 using System.Collections.Generic;
 using Xunit;
 
 namespace System.Linq.Tests
 {
-    public class ZipTests : EnumerableTests
+    public partial class ZipTests : EnumerableTests
     {
         [Fact]
         public void ImplicitTypeParameters()