Simple autocompletion for the REPL (fixes #59)

[skeeto]

Thanks for giving this a shot. There are two minor things still needed: (require 'company) and adding company (0.9.2?) as a new dependency in skewer-mode-pkg.el.

But more importantly, how do I use this? I've never used company-mode before. I fired up the REPL, enabled company-mode, and can't really get it to do anything. I can tell roughly what it's doing — figuring out the name of the object to query and fetching its properties — but I don't know how that connects to company-mode.

[TatriX]

Usually company mode will run a completion after a short delay if there are more then company-minimum-prefix-length characters in the prefix.

(add-hook 'after-init-hook 'global-company-mode)
(global-set-key (kbd "C-M-i") 'company-complete)

[TatriX]

I believe users don't need company mode to use the skewer-mode. When buffer enters the skewer-repl-mode it just sets local variable:

(setq-local company-backends '(company-skewer-repl))

So if user has company mode installed it completion should work out of the box. If no company mode available nothing happens.

[skeeto]

Opportunistic use of company-mode is perfect! I've merged with additional changes.

• I wrapped the three places it touches company-mode with with-no-warning to keep the compiler quiet. All three are perfectly safe without company-mode being loaded.

• I moved the JavaScript out into skewer.js. It's now a formal Skewer "method" called completions. The string-building hack is no longer necessary and accessing completions is a lot simpler:

(skewer-eval-synchronously "document.location"
                           :type "completions"
                           :extra '((regexp . "^h")))

;; => ((value . ["href" "host" "hostname" "hash"])
;;     (status . "success")
;;     (type . "completions")
;;     (id . "24219a5f06cbc5c"))

• skewer-repl--get-completion-expression returns nil instead of window. This is because an arg of of "window" is fundamentally different than an arg that needs to consult window, and they must be handled differently. Without this there's also the funky issue where an arg of "document" returned "window" and then pattern ends up as "t" because the substring goes off the length of "window". This fixes top-level completions.

[TatriX]

Awesome, thank you!