Replacing text across projects
If you have
ag (silver searcher),
ack installed, replacing an occurrence of text in
several files can be performed via helm-ag.
To replace all
foo occurrences by
bar in your current project:
SPC / followed by a search pattern, which displays a helm popup showing all matching text across all your project files
C-c C-e opens a new buffer with all the search results, which you can edit.
SPC s e on a selected piece of text will highlight all occurences in the search results and allow you to change them all concurrently.
fd to leave iedit state (twice if in Evil insert mode).
C-c C-c to commit the changes you have just made, which will automatically update all the files in your project with these changes.
C-c C-k if you want to cancel your changes instead.
Add animated gif / video example
helm-ag despite its name works with all the search tools, except for