vimdiff:tldr:b72bc

The :diffupdate command is a Vim command used in conjunction with Vim's diff mode.

Diff mode in Vim allows you to compare two or more files side by side and see the differences between them. It can be particularly useful for comparing different versions of a file or for collaborating with others.

The :diffupdate command updates the diff highlighting in the currently active diff windows. It ensures that the highlighting accurately reflects the current state of the compared files.

When you make changes to the files being compared, such as adding or deleting lines, the differences can become out of sync with the highlighting. By executing :diffupdate, you can refresh the diff highlighting to accurately represent the current differences between the files.

In summary, :diffupdate is used to update the highlighting in diff windows to accurately reflect the differences between compared files.