Remove the struct-based iterator for RepeatedField.

We don't use it in the runtime or generated code anywhere now, so the extra small performance boost isn't as critical, and it has some undesirable consequences.

The tests have needed to change as iterator block enumerators don't throw when we might expect them to.

2 files changed, 6 insertions, 63 deletions

diff --git a/csharp/src/ProtocolBuffers.Test/Collections/RepeatedFieldTest.cs b/csharp/src/ProtocolBuffers.Test/Collections/RepeatedFieldTest.cs
index 6eff8683..25be7731 100644
--- a/csharp/src/ProtocolBuffers.Test/Collections/RepeatedFieldTest.cs
+++ b/csharp/src/ProtocolBuffers.Test/Collections/RepeatedFieldTest.cs
@@ -241,18 +241,12 @@ namespace Google.Protobuf.Collections
             var list = new RepeatedField<string> { "first", "second" };
             using (var enumerator = list.GetEnumerator())
             {
-                Assert.Throws<InvalidOperationException>(() => enumerator.Current.GetHashCode());
                 Assert.IsTrue(enumerator.MoveNext());
                 Assert.AreEqual("first", enumerator.Current);
                 Assert.IsTrue(enumerator.MoveNext());
                 Assert.AreEqual("second", enumerator.Current);
                 Assert.IsFalse(enumerator.MoveNext());
-                Assert.Throws<InvalidOperationException>(() => enumerator.Current.GetHashCode());
                 Assert.IsFalse(enumerator.MoveNext());
-                enumerator.Reset();
-                Assert.Throws<InvalidOperationException>(() => enumerator.Current.GetHashCode());
-                Assert.IsTrue(enumerator.MoveNext());
-                Assert.AreEqual("first", enumerator.Current);
             }
         }
 
diff --git a/csharp/src/ProtocolBuffers/Collections/RepeatedField.cs b/csharp/src/ProtocolBuffers/Collections/RepeatedField.cs
index a09c7954..8375ae0b 100644
--- a/csharp/src/ProtocolBuffers/Collections/RepeatedField.cs
+++ b/csharp/src/ProtocolBuffers/Collections/RepeatedField.cs
@@ -288,14 +288,12 @@ namespace Google.Protobuf.Collections
             }
         }
 
-        public RepeatedField<T>.Enumerator GetEnumerator()
+        public IEnumerator<T> GetEnumerator()
         {
-            return new Enumerator(this);
-        }
-
-        IEnumerator<T> IEnumerable<T>.GetEnumerator()
-        {
-            return GetEnumerator();
+            for (int i = 0; i < count; i++)
+            {
+                yield return array[i];
+            }
         }
 
         public override bool Equals(object obj)
@@ -467,55 +465,6 @@ namespace Google.Protobuf.Collections
             }
             Remove((T)value);
         }
-        #endregion
-
-        public struct Enumerator : IEnumerator<T>
-        {
-            private int index;
-            private readonly RepeatedField<T> field;
-
-            public Enumerator(RepeatedField<T> field)
-            {
-                this.field = field;
-                this.index = -1;
-            }
-
-            public bool MoveNext()
-            {
-                if (index + 1 >= field.Count)
-                {
-                    index = field.Count;
-                    return false;
-                }
-                index++;
-                return true;
-            }
-
-            public void Reset()
-            {
-                index = -1;
-            }
-
-            public T Current
-            {
-                get
-                {
-                    if (index == -1 || index >= field.count)
-                    {
-                        throw new InvalidOperationException();
-                    }
-                    return field.array[index];
-                }
-            }
-
-            object IEnumerator.Current
-            {
-                get { return Current; }
-            }
-
-            public void Dispose()
-            {
-            }
-        }
+        #endregion        
     }
 }