Re: On the adoption of transient.el

[Juri Linkov]

>    > (defun restore-source-file ()
>    >   (with-current-buffer (current-buffer)
>    >     (erase-buffer)
>    >     (insert-buffer "*diff-commit-hunk*")
>    >     (write-file (current-buffer-file-name)))
>    >   (remove-hook 'vc-checkin-hook 'restore-source-file))
>
>    IIUC, it copies the old file back without merging changes in the same file.
>
> I'm not sure what you mean.  What scenario are you thinking of?  The
> "old file" is the one that contains any changes you are working with.

This is what I meant: when a file already contains some changes that should
not be committed, and some other changes need to be committed from a patch
in the same file (let's name these changesets as "old" and "new"), then
you save the old file contents temporarily, commit a patch with "new"
changes, and restore the old file contents.  As a result, when you do
'C-x v =' (vc-diff) on such file, it will show the diff that includes
the already committed "new" changes, because these changes were never
merged to the old file.

>    OTOH, `commit-patch` uses `interdiff` (for non-git VCSs)
>    to compute differences between two changesets.  Then vc
>    could use something like your diff-commit-hunk.el
>    for non-git VCSs to implement generic support for stash.
>
> What are commit-patch and interdiff?  Since diff-commit-hunk.el works
> well for git (and really for any VCS), why have a different system
> there?

`interdiff` used by https://github.com/caldwell/commit-patch
is a command that shows the differences between two diff files,
that could help to merge changes from the patch to the working copy
of the same file.