In ST2, jump_prev run as expected. But in st3, jump_prev is deprecated and changed to jump_back.
When performing a function jump, jump to a function or class and then click with a few clicks. The jump_back returns the position of the previous cursor.
In other editors, jump_back returns to the previous function or class.
Returning the cursor position is too unfriendly to use. Please provide a built-in command to jump between functions.