Correction to my above message, I meant to reference
`repo_diff_setup`, not `git_diff_ui_config` as that lets you
initialise a struct with the default context value that diff uses
(assuming I have understood correctly)

On Fri, 2 May 2025 at 17:14, Leon Michalak [off-list ref] wrote:

Inheriting the diff.context setting is what scratches my itch the most, although
also being able to set the context in the command list of `add -i`
sounds interesting too. Personally, I don't think I would use the
command line overrides too much myself as most of the time (like with
diff) I'd like to set the option and forget it but it does have a
certain consistency to it.

Slightly off-topic to the discussion, but does anyone have advice on
how to deal with providing a sentinel value for something like
context? I'd expect to pass `--unified` to the underlying diff command
*only* if the user specifically has overridden it via command line
option or a diff.context config, just like diff.algorithm has done,
however diff.algorithm is a `char *` so the value can be NULL which is
a good sentinel value. My thinking is then the underlying command can
just deal with the value as it sees it, such as giving a default if
not provided or making sure it's a minimum of 0 etc. Otherwise the
level above has to deal with it which then probably involves
`git_diff_ui_config` and other validations which I don't even think is
it's responsibility and would probably duplicate logic unncessarily?

I may be completely off in my assumptions here being new to the
codebase, so if anyone has any thoughts I'd greatly appreciate any
comments!

On Fri, 2 May 2025 at 15:39, Phillip Wood [off-list ref] wrote:

quoted

On 29/04/2025 10:16, Leon Michalak wrote:

quoted

(https://stackoverflow.com/questions/6711670/git-show-more-context-when-using-git-add-i-or-git-add-e)
which mentions you can do `GIT_DIFF_OPTS=-u<number> git add -p` which
does work however isn't very user friendly or convenient.

This is a question for others on the list rather than Leon - is it
intentional that the plumbing diff commands respect GIT_DIFF_OPTS? If a
script that wants to create a diff with a certain number of context
lines runs `git diff-index -U <context>` is it helpful for that to be
overridden if GIT_DIFF_OPTS happens to be set in the environment?
Looking at the history it seems that environment variable used to be the
only way to override the default context setting but that's not the case
now.

Best Wishes

Phillip