Bug: Not showing warning when we don't show the full diff in a merge request
When the merge request contains more files than a set limit (either 1000, or 3000 at the moment depending on a feature flag), we do not show files beyond this limit, known as overflow. So when the diff overflows, we do not show the limit, instead we are meant to show a warning to the user that files are not shown as here:
Instead we do not do this anymore, as seen here:
The current warning is shown, when we request the data from gitaly (ie, looking at individual commits), and not when looking at the merge request diff.
What seems to be happening is that when we reload the diff in the refresh service, we send the limit to Gitaly, which then returns the limit but tells us there is overflow (https://gitlab.com/gitlab-org/gitlab/-/blob/8d5fb3c7cdc8e995e1d003f6f5b61e72ba78677e/lib/gitlab/git/diff_collection.rb#L170). We use this and set the 3000+ in the files changed (https://gitlab.com/gitlab-org/gitlab/-/blob/8d5fb3c7cdc8e995e1d003f6f5b61e72ba78677e/lib/gitlab/git/diff_collection.rb#L113). However, when we retrieve the diff files from external storage, we don't know there is an overflow because we only get back the 3000 files exactly, and we show the size as 3000+ (https://gitlab.com/gitlab-org/gitlab/-/blob/8d5fb3c7cdc8e995e1d003f6f5b61e72ba78677e/app/models/merge_request_diff.rb#L706) but we don't show the warning.
We should be showing a warning to the user that some files are not shown.