class IO::Stream::Generic

@returns [String | Nil] The contents of the stream up until the pattern, which is consumed but not returned.
@parameter limit [Integer] The maximum number of bytes to read, including the pattern (even if chomped).
@parameter offset [Integer] The offset to start searching from.
@parameter pattern [String] The pattern to match.
Efficiently read data from the stream until encountering pattern.

def read_until(pattern, offset = 0, limit: nil, chomp: true)
	if index = index_of(pattern, offset, limit)
		return nil if limit and index >= limit
		
		@read_buffer.freeze
		matched = @read_buffer.byteslice(0, index+(chomp ? 0 : pattern.bytesize))
		@read_buffer = @read_buffer.byteslice(index+pattern.bytesize, @read_buffer.bytesize)
		
		return matched
	end
end