Of course the fact that you can refactor on IDEs is priceless for many, I hardly ever do it when I am coding but I may try to do it when editing some one else's source. How do you accomplish such a trivial task across multiple files in Vim?
I found this plugin for refactoring Ruby, but how about "any" language?
Answer
I agree with the 'Vim is not an IDE' paradigm. But there are times when there isn't an IDE. Here's what I use in those situations:
:grep, :vimgrep, :Ag, :Ggrep
Refactoring that has more to do with regular replacements I usually use :grep on my project tree and then record a macro to do the refactor - :g and :s are no brainers. Usually it'll let me quickly modify a large number of files with very little effort. Honestly, I use this method more than any other.
Depending on your workflow the built-in commands might be slow/inconvenient. If you use git, then you'll wanna use the excellent Fugitive plugin and its :Ggrep command to only search files checked into git. I also like the Silver Searcher for its speediness.
:argdo, :cdo, and :bufdo
:cdo and :argdo are handy to execute vim commands over a set of files.
command line
When it's harder to determine the list of files that need changes via :vimgrep I resort to the command line grep/find commands to more closely curate the list of files that I need to refactor. Save the list to a text file and use :e and a mashup of macro recordings to make the changes I need to make.
I find that the less rusty I keep my macro recording skills the more useful I find Vim for refactoring: feeling comfortable saving/restoring from registers, incrementing/decrementing register counter variables, cleaning/saving macro recordings to file for later use, etc.
Update
Since writing this more videocasts for the methods I describe have been published on vimcasts.org (I encourage you to watch ALL the Vimcasts!). For refactoring watch these ones:
- Substitution with :Subvert
- Project wide search/replace
- Search multiple files with :vimgrep
- Use :argdo to change multiple files
Vimgolf is also a great way to practice.
The ubiquity of Language Server Protocol servers since I wrote this answer have also brought some refactoring ability to Vim (and other editors). IMO they are a long way from the equaling the ability of refactoring capabilities you would see in a purpose-built IDE (I do use them, and prefer coc and ALE). See other answers on this question for more info!