diff --git a/csharp/src/Google.Protobuf.Test/SampleMessages.cs b/csharp/src/Google.Protobuf.Test/SampleMessages.cs
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+++ b/csharp/src/Google.Protobuf.Test/SampleMessages.cs
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+﻿#region Copyright notice and license
+// Protocol Buffers - Google's data interchange format
+// Copyright 2015 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#endregion
+
+using System;
+using Google.Protobuf.TestProtos;
+
+namespace Google.Protobuf
+{
+    /// <summary>
+    /// Helper methods to create sample instances of types generated from unit test messages.
+    /// </summary>
+    public class SampleMessages
+    {
+        /// <summary>
+        /// Creates a new sample TestAllTypes message with all fields populated.
+        /// The "oneof" field is populated with the string property (OneofString).
+        /// </summary>
+        public static TestAllTypes CreateFullTestAllTypes()
+        {
+            return new TestAllTypes
+            {
+                SingleBool = true,
+                SingleBytes = ByteString.CopyFrom(1, 2, 3, 4),
+                SingleDouble = 23.5,
+                SingleFixed32 = 23,
+                SingleFixed64 = 1234567890123,
+                SingleFloat = 12.25f,
+                SingleForeignEnum = ForeignEnum.FOREIGN_BAR,
+                SingleForeignMessage = new ForeignMessage { C = 10 },
+                SingleImportEnum = ImportEnum.IMPORT_BAZ,
+                SingleImportMessage = new ImportMessage { D = 20 },
+                SingleInt32 = 100,
+                SingleInt64 = 3210987654321,
+                SingleNestedEnum = TestAllTypes.Types.NestedEnum.FOO,
+                SingleNestedMessage = new TestAllTypes.Types.NestedMessage { Bb = 35 },
+                SinglePublicImportMessage = new PublicImportMessage { E = 54 },
+                SingleSfixed32 = -123,
+                SingleSfixed64 = -12345678901234,
+                SingleSint32 = -456,
+                SingleSint64 = -12345678901235,
+                SingleString = "test",
+                SingleUint32 = UInt32.MaxValue,
+                SingleUint64 = UInt64.MaxValue,
+                RepeatedBool = { true, false },
+                RepeatedBytes = { ByteString.CopyFrom(1, 2, 3, 4), ByteString.CopyFrom(5, 6), ByteString.CopyFrom(new byte[1000]) },
+                RepeatedDouble = { -12.25, 23.5 },
+                RepeatedFixed32 = { UInt32.MaxValue, 23 },
+                RepeatedFixed64 = { UInt64.MaxValue, 1234567890123 },
+                RepeatedFloat = { 100f, 12.25f },
+                RepeatedForeignEnum = { ForeignEnum.FOREIGN_FOO, ForeignEnum.FOREIGN_BAR },
+                RepeatedForeignMessage = { new ForeignMessage(), new ForeignMessage { C = 10 } },
+                RepeatedImportEnum = { ImportEnum.IMPORT_BAZ, ImportEnum.IMPORT_ENUM_UNSPECIFIED },
+                RepeatedImportMessage = { new ImportMessage { D = 20 }, new ImportMessage { D = 25 } },
+                RepeatedInt32 = { 100, 200 },
+                RepeatedInt64 = { 3210987654321, Int64.MaxValue },
+                RepeatedNestedEnum = { TestAllTypes.Types.NestedEnum.FOO, TestAllTypes.Types.NestedEnum.NEG },
+                RepeatedNestedMessage = { new TestAllTypes.Types.NestedMessage { Bb = 35 }, new TestAllTypes.Types.NestedMessage { Bb = 10 } },
+                RepeatedPublicImportMessage = { new PublicImportMessage { E = 54 }, new PublicImportMessage { E = -1 } },
+                RepeatedSfixed32 = { -123, 123 },
+                RepeatedSfixed64 = { -12345678901234, 12345678901234 },
+                RepeatedSint32 = { -456, 100 },
+                RepeatedSint64 = { -12345678901235, 123 },
+                RepeatedString = { "foo", "bar" },
+                RepeatedUint32 = { UInt32.MaxValue, UInt32.MinValue },
+                RepeatedUint64 = { UInt64.MaxValue, UInt32.MinValue },
+                OneofString = "Oneof string"                
+            };
+        }
+    }
+}