CSHARP-1224: Add BaseTextWriter property to JsonWriter.

Author: rstam

src/MongoDB.Bson.Tests/IO/JsonWriterTests.cs

@@ -42,11 +42,13 @@ public TestData(T value, string expected)
         [Test]
         public void JsonWriter_should_support_writing_multiple_documents(
             [Range(0, 3)]
-            int numberOfDocuments)
+            int numberOfDocuments,
+            [Values("", " ", "\r\n")]
+            string documentSeparator)
         {
             var document = new BsonDocument("x", 1);
             var json = document.ToJson();
-            var expectedResult = Enumerable.Repeat(json, numberOfDocuments).Aggregate("", (a, j) => a + j);
+            var expectedResult = Enumerable.Repeat(json, numberOfDocuments).Aggregate("", (a, j) => a + j + documentSeparator);
 
             using (var stringWriter = new StringWriter())
             using (var jsonWriter = new JsonWriter(stringWriter))
@@ -57,6 +59,7 @@ public void JsonWriter_should_support_writing_multiple_documents(
                     jsonWriter.WriteName("x");
                     jsonWriter.WriteInt32(1);
                     jsonWriter.WriteEndDocument();
+                    jsonWriter.BaseTextWriter.Write(documentSeparator);
                 }
 
                 var result = stringWriter.ToString();

src/MongoDB.Bson/IO/JsonWriter.cs

@@ -61,6 +61,18 @@ public JsonWriter(TextWriter writer, JsonWriterSettings settings)
             State = BsonWriterState.Initial;
         }
 
+        // public properties
+        /// <summary>
+        /// Gets the base TextWriter.
+        /// </summary>
+        /// <value>
+        /// The base TextWriter.
+        /// </value>
+        public TextWriter BaseTextWriter
+        {
+            get { return _textWriter; }
+        }
+
         // public methods
         /// <summary>
         /// Closes the writer.