File-visiting buffers are by default saved at certain points in time. This doesn’t guarantee that Magit buffers are always up-to-date, but, provided one only edits files by editing them in Emacs and uses only Magit to interact with Git, one can be fairly confident. When in doubt or after outside changes, type
magit-refresh) to save and refresh explicitly.
user option magit-save-repository-buffers
This option controls whether file-visiting buffers are saved before certain events.
If this is non-nil then all modified file-visiting buffers belonging to the current repository may be saved before running commands, before creating new Magit buffers, and before explicitly refreshing such buffers. If this is
dontask then this is done without user intervention. If it is
t then the user has to confirm each save.