Eugenio Lacuesta

This is not entirely clear to me, can you provide an example? Also, we would need tests before merging.

You shouldn't use partials as callbacks. It used to be the case that it could indirectly cause serialization issues (see https://github.com/scrapy/scrapy/issues/1138#issuecomment-93824213), this exception is different because the code is newer...

It's an underscored class, and it's not used anywhere. My vote goes to just removing it.

@kmike I started working on this (on #4945, rather) after #4923. This would provide a way of dealing with cached responses in an uniform fashion, taking the burden off from...

This is technically backward-incompatible, but I don't think that's too much of a problem in practice (I believe invalidating an existing cache after a Scrapy version change is probably reasonable).

Thanks! There are two additional occurrences: * https://github.com/scrapy/scrapy/blob/2.4.1/scrapy/core/downloader/handlers/http11.py#L404 * https://github.com/scrapy/scrapy/blob/2.4.1/scrapy/core/downloader/handlers/http11.py#L523

@nemec #4205 was merged, which means now there is a way to monitor the progress of a given request. Are you still interested in adding a progress bar extension?

Related: #5103

@akshaysharmajs Regarding the tests failing for the "pinned" environments, that's because the dependencies section for them do not inherit the main dependencies in `tox.ini`. Adding `git+https://github.com/scrapy/xtractmime.git@binary#egg=xtractmime` [here](https://github.com/scrapy/scrapy/blob/2.5.0/tox.ini#L71) should work.

Transferred the issue here since it doesn't seem to be a problem with Scrapy specifically but rather with Parsel, the underlying selector library: ```python In [1]: from parsel import Selector,...