Refactor within a project

SPC s p (helm-swoop) searches the text of all project files, displaying the results in a helm popup.

C-c C-e opens the search results in a buffer for editing. Changes in this buffer can be applied back to the relevant files in the project.

# or * on a function name (or any text) will select all instances, opening the transient buffer menu.

e starts iedit, placing a cursor on each instance to make multiple simultaneous changes. Multiple cursors or the usual editing commands can also be used to make changes.

C-c C-c to commit the changes and update all the relevant files in the project. C-c C-k to changes and keep the project files as they were.