diff-beginning-of-hunk
diff-beginning-of-hunk is a compiled Lisp function in `diff-mode.el
'.
(diff-beginning-of-hunk &optional TRY-HARDER)
Move back to the previous hunk beginning, and return its position.
If point is in a file header rather than a hunk, advance to the
next hunk if TRY-HARDER is non-nil; otherwise signal an error.