From 3948255445bc4445f5688b4b305a06feac31d4ec Mon Sep 17 00:00:00 2001
From: Henrik Lissner <henrik@lissner.net>
Date: Tue, 31 Jul 2018 14:22:38 +0200
Subject: [PATCH] lang/ruby: rewrite rbenv support; add rvm support

---
 modules/lang/ruby/autoload.el | 17 +++++++++++
 modules/lang/ruby/config.el   | 56 ++++++++++++++++-------------------
 modules/lang/ruby/packages.el |  6 ++--
 3 files changed, 46 insertions(+), 33 deletions(-)

diff --git a/modules/lang/ruby/autoload.el b/modules/lang/ruby/autoload.el
index 8f9519283..980fdd2ce 100644
--- a/modules/lang/ruby/autoload.el
+++ b/modules/lang/ruby/autoload.el
@@ -13,3 +13,20 @@ buffers open."
           (when (processp process)
             (kill-process (get-buffer-process inf-buffer))
             (kill-buffer inf-buffer)))))))
+
+;;;###autoload
+(defun +ruby-version ()
+  "Return the currently installed version of ruby on your system (the first
+ruby executable found in your PATH).
+
+This is not necessarily aware of env management tools like virtualenv, pyenv or
+pipenv, unless those tools have modified the PATH that Emacs picked up when you
+started it."
+  (unless (executable-find "ruby")
+    (user-error "Couldn't find ruby executable in PATH"))
+  (with-temp-buffer
+    (let ((p (call-process "ruby" nil (current-buffer) nil "--version"))
+          (output (string-trim (buffer-string))))
+      (unless (zerop p)
+        (user-error "ruby --version failed: %s" output))
+      (nth 1 (split-string output " " t)))))
diff --git a/modules/lang/ruby/config.el b/modules/lang/ruby/config.el
index 5c668a533..d787ffaf0 100644
--- a/modules/lang/ruby/config.el
+++ b/modules/lang/ruby/config.el
@@ -1,10 +1,9 @@
 ;;; lang/ruby/config.el -*- lexical-binding: t; -*-
 
-(defvar +ruby-rbenv-versions nil
-  "Available versions of ruby in rbenv.")
-
-(defvar-local +ruby-current-version nil
-  "The currently active ruby version.")
+(defvar +ruby-mode-name-functions '(+ruby-version)
+  "A list of functions to retrieve a version or environment string from. The
+first to return non-nil will have its result appended to the ruby-mode
+`mode-name' and displayed in the mode-line.")
 
 
 ;;
@@ -18,47 +17,24 @@
   :mode "\\.\\(?:pry\\|irb\\)rc\\'"
   :mode "/\\(?:Gem\\|Cap\\|Vagrant\\|Rake\\|Pod\\|Puppet\\|Berks\\)file\\'"
   :config
-  (set-env! "RBENV_ROOT")
   (set-electric! 'enh-ruby-mode :words '("else" "end" "elsif"))
   (set-repl-handler! 'enh-ruby-mode #'inf-ruby) ; `inf-ruby'
 
   ;; so class and module pairs work
   (setq-hook! 'enh-ruby-mode-hook sp-max-pair-length 6)
 
-  ;; Version management with rbenv
   (defun +ruby|add-version-to-modeline ()
     "Add version string to the major mode in the modeline."
     (setq mode-name
-          (if +ruby-current-version
-              (format "Ruby %s" +ruby-current-version)
+          (if-let* ((result (run-hook-with-args-until-success '+ruby-mode-name-functions)))
+              (format "Ruby %s" result)
             "Ruby")))
-  (add-hook 'enh-ruby-mode-hook #'+ruby|add-version-to-modeline)
-
-  (if (not (executable-find "rbenv"))
-      (setq-default +ruby-current-version (string-trim (shell-command-to-string "ruby --version 2>&1 | cut -d' ' -f2")))
-    (setq +ruby-rbenv-versions (split-string (shell-command-to-string "rbenv versions --bare") "\n" t))
-
-    (defun +ruby|detect-rbenv-version ()
-      "Detect the rbenv version for the current project and set the relevant
-environment variables."
-      (when-let* ((version-str (shell-command-to-string "RBENV_VERSION= ruby --version 2>&1 | cut -d' ' -f2")))
-        (setq version-str (string-trim version-str)
-              +ruby-current-version version-str)
-        (when (member version-str +ruby-rbenv-versions)
-          (setenv "RBENV_VERSION" version-str))))
-    (add-hook 'enh-ruby-mode-hook #'+ruby|detect-rbenv-version)))
+  (add-hook 'enh-ruby-mode-hook #'+ruby|add-version-to-modeline))
 
 
 (def-package! yard-mode :hook enh-ruby-mode)
 
 
-(def-package! rbenv
-  :after enh-ruby-mode
-  :config
-  (when (executable-find "rbenv")
-    (global-rbenv-mode +1)))
-
-
 (def-package! rubocop
   :hook (enh-ruby-mode . rubocop-mode)
   :config
@@ -127,3 +103,21 @@ environment variables."
   :after inf-ruby
   :config (set-company-backend! 'inf-ruby-mode 'company-inf-ruby))
 
+
+;;
+;; Version managers
+;;
+
+(def-package! rbenv
+  :when (featurep! +rbenv)
+  :after enh-ruby-mode
+  :config
+  (set-env! "RBENV_ROOT")
+  (when (executable-find "rbenv")
+    (global-rbenv-mode +1)))
+
+
+(def-package! rvm
+  :when (featurep! +rvm)
+  :after enh-ruby-mode)
+
diff --git a/modules/lang/ruby/packages.el b/modules/lang/ruby/packages.el
index 661a8d1b8..5bcef5610 100644
--- a/modules/lang/ruby/packages.el
+++ b/modules/lang/ruby/packages.el
@@ -4,7 +4,6 @@
 ;; requires ruby ruby-lint
 
 (package! enh-ruby-mode)
-(package! rbenv)
 (package! rubocop)
 (package! inf-ruby)
 (package! rspec-mode)
@@ -15,4 +14,7 @@
 (when (featurep! :completion company)
   (package! company-inf-ruby))
 
-
+(when (featurep! +rbenv)
+  (package! rbenv))
+(when (featurep! +rvm)
+  (package! rvm))