Ensure not null values

Author: Arno Janssen

Source/HttpMultipartParser.UnitTests/StreamingMultipartFormDataParserUnitTests.cs

@@ -63,5 +63,21 @@ public async Task CanHandleNullDelegatesAsync()
 				await parser.RunAsync(TestContext.Current.CancellationToken);
 			}
 		}
+
+		[Fact]
+		public void CanHandleDefaultOptions()
+		{
+			using (Stream stream = TestUtil.StringToStream(_testData))
+			{
+				var parser = new StreamingMultipartFormDataParser(stream);
+
+				// Intentionally setting these handlers to null to verify that we can parse the stream despite missing handlers
+				// See: https://github.com/Http-Multipart-Data-Parser/Http-Multipart-Data-Parser/issues/121
+				parser.ParameterHandler = null;
+				parser.FileHandler = null;
+
+				parser.Run();
+			}
+		}
 	}
 }

Source/HttpMultipartParser/StreamingMultipartFormDataParser.cs

@@ -106,9 +106,9 @@ public StreamingMultipartFormDataParser(Stream stream, string boundary = null, E
 			_options = new ParserOptions
 			{
 				Boundary = boundary,
-				Encoding = encoding,
+				Encoding = encoding ?? Constants.DefaultEncoding,
 				BinaryBufferSize = binaryBufferSize,
-				BinaryMimeTypes = binaryMimeTypes,
+				BinaryMimeTypes = binaryMimeTypes ?? Constants.DefaultBinaryMimeTypes,
 				IgnoreInvalidParts = ignoreInvalidParts
 			};
 
@@ -180,12 +180,12 @@ public async Task RunAsync(CancellationToken cancellationToken = default)
 		/// <summary>
 		/// Gets the binary buffer size.
 		/// </summary>
-		public int BinaryBufferSize { get; private set; }
+		public int BinaryBufferSize => _options.BinaryBufferSize;
 
 		/// <summary>
 		/// Gets the encoding.
 		/// </summary>
-		public Encoding Encoding { get; private set; }
+		public Encoding Encoding => _options.Encoding;
 
 		/// <summary>
 		/// Gets or sets the FileHandler. Delegates attached to this property will receive sequential file stream data from this parser.