refactoring stream reader, cosmetics

lib/zstds/file.rb

@@ -22,6 +22,8 @@ def self.compress(source, destination, options = {})
       open_files(source, destination) do |source_io, destination_io|
         ZSTDS._native_compress_io source_io, destination_io, options
       end
+
+      nil
     end
 
     def self.decompress(source, destination, options = {})
@@ -33,6 +35,8 @@ def self.decompress(source, destination, options = {})
       open_files(source, destination) do |source_io, destination_io|
         ZSTDS._native_decompress_io source_io, destination_io, options
       end
+
+      nil
     end
 
     private_class_method def self.open_files(source, destination, &_block)

lib/zstds/stream/raw/abstract.rb

@@ -19,6 +19,8 @@ def initialize(native_stream)
 
         def flush(&writer)
           write_result(&writer)
+
+          nil
         end
 
         protected def flush_destination_buffer(&writer)
@@ -44,6 +46,8 @@ def close(&writer)
 
           @native_stream.close
           @is_closed = true
+
+          nil
         end
 
         def closed?

lib/zstds/stream/raw/compressor.rb

@@ -73,8 +73,6 @@ def flush(&writer)
           end
 
           super
-
-          nil
         end
 
         def close(&writer)
@@ -94,8 +92,6 @@ def close(&writer)
           end
 
           super
-
-          nil
         end
       end
     end

lib/zstds/stream/raw/decompressor.rb

@@ -51,8 +51,6 @@ def flush(&writer)
           Validation.validate_proc writer
 
           super
-
-          nil
         end
 
         def close(&writer)
@@ -61,8 +59,6 @@ def close(&writer)
           Validation.validate_proc writer
 
           super
-
-          nil
         end
       end
     end

lib/zstds/stream/reader.rb

@@ -24,6 +24,10 @@ def initialize(source_io, options = {}, *args)
         @lineno = 0
       end
 
+      protected def create_raw_stream
+        Raw::Decompressor.new @options
+      end
+
       protected def initialize_source_buffer_length
         source_buffer_length = @options[:source_buffer_length]
         Validation.validate_not_negative_integer source_buffer_length unless source_buffer_length.nil?
@@ -34,10 +38,6 @@ def initialize(source_io, options = {}, *args)
         @source_buffer_length = source_buffer_length
       end
 
-      protected def create_raw_stream
-        Raw::Decompressor.new @options
-      end
-
       protected def reset_io_remainder
         @io_remainder = ::String.new :encoding => ::Encoding::BINARY
       end
@@ -103,11 +103,13 @@ def close
         super
       end
 
+      def eof?
+        @buffer.bytesize.zero? && @io.eof?
+      end
+
       # -- asynchronous --
 
       def read_nonblock(bytes_to_read, out_buffer = nil, *options)
-        raise ::EOFError if eof?
-
         read_more_to_buffer_nonblock(*options) until @buffer.bytesize >= bytes_to_read || @io.eof?
 
         read_bytes_from_buffer bytes_to_read, out_buffer
@@ -120,8 +122,14 @@ def read_nonblock(bytes_to_read, out_buffer = nil, *options)
 
       # -- common --
 
-      def eof?
-        @io.eof? && @buffer.bytesize.zero?
+      protected def append_io_data_to_buffer(io_data)
+        io_portion    = @io_remainder + io_data
+        bytes_read    = raw_wrapper :read, io_portion
+        @io_remainder = io_portion.byteslice bytes_read, io_portion.bytesize - bytes_read
+
+        # We should just ignore case when "io.eof?" appears but "io_remainder" is not empty.
+        # Ancient compress implementations can write bytes from not initialized buffer parts to output.
+        raw_wrapper :flush if @io.eof?
       end
 
       protected def read_bytes_from_buffer(bytes_to_read, out_buffer)
@@ -136,16 +144,6 @@ def eof?
         result
       end
 
-      protected def append_io_data_to_buffer(io_data)
-        io_portion    = @io_remainder + io_data
-        bytes_read    = raw_wrapper :read, io_portion
-        @io_remainder = io_portion.byteslice bytes_read, io_portion.bytesize - bytes_read
-
-        # We should just ignore case when "io.eof?" appears but "io_remainder" is not empty.
-        # Ancient compress implementations can write bytes from not initialized buffer parts to output.
-        raw_wrapper :flush if @io.eof?
-      end
-
       protected def transcode_to_internal(data)
         data = data.encode @internal_encoding, **@transcode_options unless @internal_encoding.nil?
         data