Company flow 
Flow backend for company-mode. Flow-based autocomplete for Emacs.
Installation
You can install this package from Melpa
M-x package-install RET company-flow RET
Usage
Ensure that flow is in your path.
Add to your company-backends for your preferred javascript modes, for example:
(eval-after-load 'company
(add-to-list 'company-backends 'company-flow))Configuration
company-flow-executable
Buffer local variable that should point to the flow executable. Defaults to
"flow". Set to nil to disable company-flow.
For best performance, you can set this to the actual flow binary in your project. Here's one way to do that:
(defun flow/set-flow-executable ()
(interactive)
(let* ((os (pcase system-type
('darwin "osx")
('gnu/linux "linux64")
(_ nil)))
(root (locate-dominating-file buffer-file-name "node_modules/flow-bin"))
(executable (car (file-expand-wildcards
(concat root "node_modules/flow-bin/*" os "*/flow")))))
(setq-local company-flow-executable executable)
;; These are not necessary for this package, but a good idea if you use
;; these other packages
(setq-local flow-minor-default-binary executable)
(setq-local flycheck-javascript-flow-executable executable)))
;; Set this to the mode you use, I use rjsx-mode
(add-hook 'rjsx-mode-hook #'flow/set-flow-executable t)company-flow-modes
List of major modes where company-flow should provide completions if it is
part of company-backends. Set to nil to enable company-flow for all major modes.
Thanks
- @proofit404 for a nice example backend with company-tern.
- @dgutov for company-mode and lots of feedback.
- @lunaryorn for the process communication code from flycheck.