lib/io_streams/builder.rb in iostreams-1.8.0 vs lib/io_streams/builder.rb in iostreams-1.9.0

@@ -77,19 +77,20 @@
 
     # Returns [Hash<Symbol:Hash>] the pipeline of streams
     # with their options that will be applied when the reader or writer is invoked.
     def pipeline
       return streams.dup.freeze if streams
-      return {}.freeze unless file_name
 
-      built_streams          = {}
-      # Encode stream is always first
-      built_streams[:encode] = options[:encode] if options&.key?(:encode)
+      build_pipeline.freeze
+    end
 
-      opts = options || {}
-      parse_extensions.each { |stream| built_streams[stream] = opts[stream] || {} }
-      built_streams.freeze
+    # Removes the named stream from the current pipeline.
+    # If the stream pipeline has not yet been built it will be built from the file_name if present.
+    # Note: Any options must be set _before_ calling this method.
+    def remove_from_pipeline(stream_name)
+      @streams ||= build_pipeline
+      @streams.delete(stream_name.to_sym)
     end
 
     # Returns the tabular format if set, otherwise tries to autodetect the format if the file_name has been set
     # Returns [nil] if no format is set, or if it cannot be determined from the file_name
     def format
@@ -103,9 +104,21 @@
 
       @format = format
     end
 
     private
+
+    def build_pipeline
+      return {} unless file_name
+
+      built_streams          = {}
+      # Encode stream is always first
+      built_streams[:encode] = options[:encode] if options&.key?(:encode)
+
+      opts = options || {}
+      parse_extensions.each { |stream| built_streams[stream] = opts[stream] || {} }
+      built_streams
+    end
 
     def class_for_stream(type, stream)
       ext = IOStreams.extensions[stream.nil? ? nil : stream.to_sym] ||
             raise(ArgumentError, "Unknown Stream type: #{stream.inspect}")
       ext.send("#{type}_class") || raise(ArgumentError, "No #{type} registered for Stream type: #{stream.inspect}")