'eol' documentation confusion

> Upon inspection of the gitattributes documentation page here:
> https://git-scm.com/docs/gitattributes
>
> When comparing the documentation for 'text' with 'eol', I see the
> following missing explanations for 'eol':
>
> * eol
> * -eol
>
> Maybe the fact that these are missing means they are not valid to use.
> There is also the issue that `text` usually controls EOL anyway. Is
> there ever any reason to set eol in a way differently than explained
> in the documentation (that is, `eol=lf` or `eol=crlf`)?
>
> For example, what if you want a file to be treated as text BUT you do
> not want it to perform EOL normalization at all. Could you do this?
>
>     foo.txt text -eol
>
> Just at first glance, this to me would mean line endings on checkin
> and checkout are not touched (CRLF could be checked in). Is this
> possible?
>
> What about setting `eol` but not `text`?
>
> Honestly it seems like `eol` is just a supplementary setting for
> `text` and was never intended to be used in ways that are
> undocumented. Some explanation to help uncloud this would help, or
> maybe I missed something in the documentation that explains this.

> On Sun, Jun 21, 2015 at 9:04 AM, Robert Dailey <rcdailey.lists@gmail.com> wrote:
>> Upon inspection of the gitattributes documentation page here:
>> https://git-scm.com/docs/gitattributes
>>
>> When comparing the documentation for 'text' with 'eol', I see the
>> following missing explanations for 'eol':
>>
>> * eol
>> * -eol
>>
>> Maybe the fact that these are missing means they are not valid to use.
>> There is also the issue that `text` usually controls EOL anyway. Is
>> there ever any reason to set eol in a way differently than explained
>> in the documentation (that is, `eol=lf` or `eol=crlf`)?

> eol=lf or eol=crlf are the only useful settings.
> Everything else is ignored because it does not make sense.
>
> See convert.c:
> static enum eol git_path_check_eol()

> Torsten Bögershausen <tboegi@web.de> writes:
> 
>> eol=lf or eol=crlf are the only useful settings.
>> Everything else is ignored because it does not make sense.
>>
>> See convert.c:
>> static enum eol git_path_check_eol()
> 
> That makes me wonder...
> 
> The original reasoning behind the current behaviour that we ignore
> unknown values given to configuration variables and attributes is so
> that people can use the same file that has values that are
> understood by newer versions of Git with older versions of Git.
> 
> You may be trying the eol=cleverLF setting introduced in Git version
> 47-prerelease by adding it to .git/info/attributes, and may have
> found it useful.  But you may also have to use the same repository
> on another machine that you didn't install that future version of
> Git over the network filesystem.  Barfing and not proceeding when we
> see unknown eol=cleverLF does not sound like a nice thing to do,
> which is why we just ignore and behave as if the setting was not
> there.
> 
> Ideally, however, I think we should ignore an unknown setting as
> long as it does not matter (i.e. we do not come to the codepath that
> wants to know eol settings for the path, e.g. running "git log" to
> show only the commit log messages and the topology of the history),
> but we should error out when the unknown setting possibly matters
> (i.e. we do need the eol setting for the path in order to correctly
> convert the contents to end-user's liking).
> 
> Thoughts (and patches ;-)?