Re: [FR] Make notion of "modification time" configurable during publishing

[Suhail Singh]

Ihor Radchenko writes:

> I am a bit confused. What do you mean by "git author date" and "git
> commit date"?

In the output of `git log --pretty=fuller`, there is AuthorDate which is
distinct from CommitDate. In case unfamiliar, an elaboration on the
distinction: <https://stackoverflow.com/a/11857467>.

> I think that we should use an alternative approach. Both "git time" and
> "fs time" are only an approximation. The true decision to re-publish an
> article should be triggered by article text being modified. So, we may
> better decide based on the file text hash, not the modification times.

For it to work, the "file text hash" would have to also take into
account the "file text hash" of included files, or the decision to
re-publish would have to be predicated on the hash of included files as
well. I.e., the equivalent of this logic in
org-publish-cache-file-needs-publishing :

        (let ((mtime (org-publish-cache-mtime-of-src filename)))
          (or (time-less-p pstamp mtime)
              (cl-some (lambda (ct) (time-less-p mtime ct))
                       included-files-mtime)))

But assuming the existence of equivalent logic, yes something like a
file hash would work. In fact, at least in the case of git, the VCS
could even be queried for it (via git hash-object).

-- 
Suhail