René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"The _remaining_capacity \u003e _bytes_in_buffer check in bufsocket.py is unnecessary","articleBody":"This is not an actual issue, but a possible tiny improvement.\r\n\r\n**TL;DR**\r\nI think this check `self._remaining_capacity \u003e self._bytes_in_buffer` in [bufsocket.py#L141](https://github.com/Lukasa/hyper/blob/development/hyper/common/bufsocket.py#L141) is unnecessary.\r\n\r\nHere's why.\r\nFrom the definitions we know:\r\n```python\r\n  self._remaing_capacity - self._bytes_in_buffer\r\n= (self._buffer_size - self._index) - self._bytes_in_buffer\r\n= self._buffer_size - (self._index + self._bytes_in_buffer)\r\n= self._buffer_size - self._buffer_end    \r\n```\r\n\r\nWe also know that each time `self._bytes_in_buffer` increases, the increment is less than \r\n  `_buffer_size - _buffer_end`. An example:\r\n```python\r\nif (self._remaining_capacity \u003e self._bytes_in_buffer and should_read):\r\n    count = self._sck.recv_into(self._buffer_view[self._buffer_end:])\r\n    if not count and amt \u003e self._bytes_in_buffer:\r\n        raise ConnectionResetError()\r\n    self._bytes_in_buffer += count   # count cannot be greater than _buffer_size - _buffer_end\r\n```\r\n\r\nNow we have two formulas:\r\n```\r\n_buffer_size - _buffer_end = _remaing_capacity - _bytes_in_buffer    ①\r\ncount \u003c _buffer_size - _buffer_end                                   ②   \r\n```\r\n\r\nThus `_bytes_in_buffer \u003c _remaing_capacity` is always `True`.\r\n```\r\n  _bytes_in_buffer(new) \r\n= _bytes_in_buffer(old) + count \r\n\u003c _bytes_in_buffer + _buffer_size - _buffer_end \r\n= _remaing_capacity\r\n```\r\n\r\nI intended to remove the check and run tests, but unfortunately I was not able to finish them(I have all the test deps installed and run `make test`, don't know why it takes so long). So I'm not 100% sure it can be removed.","author":{"url":"https://github.com/laike9m","@type":"Person","name":"laike9m"},"datePublished":"2017-01-12T15:13:33.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":6},"url":"https://github.com/300/hyper/issues/300"}