From 72823fee04a9e48e3bd5edf7fdd4b57b42ecb174 Mon Sep 17 00:00:00 2001
From: leandromoh <leandromoh@hotmail.com>
Date: Wed, 1 May 2019 16:48:40 -0300
Subject: [PATCH 1/4] add validation for dispose once

---
 MoreLinq.Test/TestingSequence.cs | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/MoreLinq.Test/TestingSequence.cs b/MoreLinq.Test/TestingSequence.cs
index 6abdac68e..e0c789aa7 100644
--- a/MoreLinq.Test/TestingSequence.cs
+++ b/MoreLinq.Test/TestingSequence.cs
@@ -67,7 +67,11 @@ public IEnumerator<T> GetEnumerator()
             Assert.That(_sequence, Is.Not.Null, "LINQ operators should not enumerate a sequence more than once.");
             var enumerator = _sequence.GetEnumerator().AsWatchtable();
             _disposed = false;
-            enumerator.Disposed += delegate { _disposed = true; };
+            enumerator.Disposed += delegate 
+            { 
+                Assert.That(_disposed, Is.False, "LINQ operators should not dispose a sequence more than once.");
+                _disposed = true; 
+            };
             enumerator.MoveNextCalled += delegate { MoveNextCallCount++; };
             _sequence = null;
             return enumerator;

From e529fc1f4052fc2585c4d59344657db4f3b81fde Mon Sep 17 00:00:00 2001
From: leandromoh <leandromoh@hotmail.com>
Date: Wed, 1 May 2019 16:48:53 -0300
Subject: [PATCH 2/4] flatten fix

---
 MoreLinq/Flatten.cs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/MoreLinq/Flatten.cs b/MoreLinq/Flatten.cs
index 1369a6945..e98466c3e 100644
--- a/MoreLinq/Flatten.cs
+++ b/MoreLinq/Flatten.cs
@@ -123,6 +123,7 @@ public static IEnumerable<object> Flatten(this IEnumerable source, Func<object,
                         }
 
                         (e as IDisposable)?.Dispose();
+                        e = null;
                     }
                 }
                 finally

From ddac1efffa6b2df8201351902812e226ab08d7b9 Mon Sep 17 00:00:00 2001
From: leandromoh <leandromoh@hotmail.com>
Date: Wed, 1 May 2019 16:49:09 -0300
Subject: [PATCH 3/4] zipimpl fix

---
 MoreLinq/ZipImpl.cs | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/MoreLinq/ZipImpl.cs b/MoreLinq/ZipImpl.cs
index 8341e518e..2005660cb 100644
--- a/MoreLinq/ZipImpl.cs
+++ b/MoreLinq/ZipImpl.cs
@@ -34,17 +34,19 @@ static IEnumerable<TResult> ZipImpl<T1, T2, T3, T4, TResult>(
             int limit,
             Folder<IEnumerator, Exception> errorSelector = null)
         {
-            IEnumerator<T1> e1;
-            IEnumerator<T2> e2;
-            IEnumerator<T3> e3;
-            IEnumerator<T4> e4;
+            IEnumerator<T1> e1 = null;
+            IEnumerator<T2> e2 = null;
+            IEnumerator<T3> e3 = null;
+            IEnumerator<T4> e4 = null;
             var terminations = 0;
 
-            using (e1 = s1 .GetEnumerator())
-            using (e2 = s2 .GetEnumerator())
-            using (e3 = s3?.GetEnumerator())
-            using (e4 = s4?.GetEnumerator())
+            try
             {
+                e1 = s1 .GetEnumerator();
+                e2 = s2 .GetEnumerator();
+                e3 = s3?.GetEnumerator();
+                e4 = s4?.GetEnumerator();
+
                 while (true)
                 {
                     var n = 0;
@@ -59,6 +61,13 @@ static IEnumerable<TResult> ZipImpl<T1, T2, T3, T4, TResult>(
                         yield break;
                 }
             }
+            finally
+            {
+                e1?.Dispose();
+                e2?.Dispose();
+                e3?.Dispose();
+                e4?.Dispose();
+            }
 
             T Read<T>(ref IEnumerator<T> e, int n)
             {

From 4022663cf5e7929d7e59d8eb2cea7c01cebb9769 Mon Sep 17 00:00:00 2001
From: leandromoh <leandromoh@hotmail.com>
Date: Wed, 1 May 2019 16:53:59 -0300
Subject: [PATCH 4/4] removed trailing spaces

---
 MoreLinq.Test/TestingSequence.cs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/MoreLinq.Test/TestingSequence.cs b/MoreLinq.Test/TestingSequence.cs
index e0c789aa7..bb805c48e 100644
--- a/MoreLinq.Test/TestingSequence.cs
+++ b/MoreLinq.Test/TestingSequence.cs
@@ -67,10 +67,10 @@ public IEnumerator<T> GetEnumerator()
             Assert.That(_sequence, Is.Not.Null, "LINQ operators should not enumerate a sequence more than once.");
             var enumerator = _sequence.GetEnumerator().AsWatchtable();
             _disposed = false;
-            enumerator.Disposed += delegate 
-            { 
+            enumerator.Disposed += delegate
+            {
                 Assert.That(_disposed, Is.False, "LINQ operators should not dispose a sequence more than once.");
-                _disposed = true; 
+                _disposed = true;
             };
             enumerator.MoveNextCalled += delegate { MoveNextCallCount++; };
             _sequence = null;