[Distutils] Round 6 - PEP 440 - Version Identification and Dependency Specification Version

[Paul Moore]

On 8 August 2014 22:53, Donald Stufft <donald at stufft.io> wrote:
> Direct references
> =================
>
> Some automated tools may permit the use of a direct reference as an
> alternative to a normal version specifier. A direct reference consists of
> the specifier ``@`` and an explicit URL.
>
> Whether or not direct references are appropriate depends on the specific
> use case for the version specifier. Automated tools SHOULD at least issue
> warnings and MAY reject them entirely when direct references are used
> inappropriately.
>
> Public index servers SHOULD NOT allow the use of direct references in
> uploaded distributions. Direct references are intended as a tool for
> software integrators rather than publishers.
>
> Depending on the use case, some appropriate targets for a direct URL
> reference may be a valid ``source_url`` entry (see PEP 426), an sdist, or
> a wheel binary archive. The exact URLs and targets supported will be tool
> dependent.
>
> For example, a local source archive may be referenced directly::
>
>     pip @ file:///localbuilds/pip-1.3.1.zip
>
> Alternatively, a prebuilt archive may also be referenced::
>
>     pip @ file:///localbuilds/pip-1.3.1-py33-none-any.whl

One very minor question. Is URL format required here? I guess so. On
Windows, file URLs are confusing and annoying to type - use of /
rather than \ makes tab-completion useless, it's difficult to remember
how many slashes go at the start and where the drive letter goes, and
do UNC paths need 157 or 158 slashes at the start (:-)), and the
documentation is inconsistent and hard to find.

Allowing a pathname here would be convenient for users, but it's 100%
not important enough to need a new version of the spec. A
clarification (presumably, that a URL is required) with a pointer to a
document that explains the relevant filename->URL translation
algorithm, would be good, though.

Paul