Derrick Stolee [off-list ref] writes:

On 9/21/2022 7:36 PM, Elijah Newren wrote:

quoted

On Wed, Sep 21, 2022 at 8:22 AM ZheNing Hu [off-list ref] wrote:

quoted

Here, we do have an object download, which occurred after the merge
completed, so there must be something happening after the merge which
needs the extra blob; if we keep reading...

quoted

 project1/file1 | 10 ++++++++++
 1 file changed, 10 insertions(+)

Ah, the 'helpful' diffstat.  It downloads blobs from a promisor remote
just so we can see what has changed, including in the area of the
project we don't care about.
...

This is an interesting find! I wonder how many people are hitting this
in the wild. Perhaps merge.stat should be added to the optional, but
recommended config options in scalar.c.

Hmph.  It somehow sounds like throwing the baby out with the
bathwater, doesn't it.

You are only interested in a few directories in the project.  You
pull from somebody else (or the central repository), and end up
getting updates to both inside and outside the areas of your
interest.

As a project gets larger and better modularized, does it become more
likely that such an update will happen more often?

I am very tempted to suggest that the diffstat after a merge in such
a project should use the sparse cone(s) as pathspec.  Disabling the
"what happened in this merge" report altogether is a way too blunt
instrument, isn't it?