Let python/ruby modules handle version strings

Also, set RBENV_VERSION and PYENV_VERSION envvars.

modules/lang/python/config.el

@@ -1,5 +1,20 @@
 ;;; lang/python/config.el -*- lexical-binding: t; -*-
 
+(defvar +python-pyenv-root nil
+  "The path to pyenv's root directory. This is automatically set when `python'
+is loaded.")
+
+(defvar +python-pyenv-versions nil
+  "Available versions of python in pyenv.")
+
+(defvar-local +python-current-version nil
+  "The currently active pyenv version.")
+
+
+;;
+;; Plugins
+;;
+
 (def-package! python
   :commands python-mode
   :init
@@ -24,6 +39,33 @@
           python-shell-completion-string-code
           "';'.join(get_ipython().Completer.all_completions('''%s'''))\n"))
 
+  ;; Version management with pyenv
+  (defun +python|add-version-to-modeline ()
+    "Add version string to the major mode in the modeline."
+    (setq mode-name
+          (if +python-current-version
+              (format "Python %s" +python-current-version)
+            "Python")))
+  (add-hook 'python-mode-hook #'+python|add-version-to-modeline)
+
+  (if (not (executable-find "pyenv"))
+      (setq +python-current-version (string-trim (shell-command-to-string "python --version 2>&1 | cut -d' ' -f2")))
+    (setq +python-pyenv-root     (string-trim (shell-command-to-string "pyenv root"))
+          +python-pyenv-versions (split-string (shell-command-to-string "pyenv versions --bare") "\n" t))
+
+    (defun +python|detect-pyenv-version ()
+      "Detect the pyenv version for the current project and set the relevant
+environment variables."
+      (when-let (version-str (shell-command-to-string "python --version 2>&1 | cut -d' ' -f2"))
+        (setq version-str (string-trim version-str)
+              +python-current-version version-str)
+        (let ((pyenv-current-path (concat +python-pyenv-root "/versions/" version-str)))
+          (when (file-directory-p pyenv-current-path)
+            (setq pythonic-environment pyenv-current-path)))
+        (when (member version-str +python-pyenv-versions)
+          (setenv "PYENV_VERSION" version-str))))
+    (add-hook 'python-mode-hook #'+python|detect-pyenv-version))
+
   (define-key python-mode-map (kbd "DEL") nil) ; interferes with smartparens
   (sp-with-modes 'python-mode
     (sp-local-pair "'" nil :unless '(sp-point-before-word-p sp-point-after-word-p sp-point-before-same-p))))

modules/lang/ruby/config.el

@@ -1,5 +1,16 @@
 ;;; 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.")
+
+
+;;
+;; Plugins
+;;
+
 (def-package! ruby-mode
   :mode ("\\.rb$" "\\.rake$" "\\.gemspec$" "\\.?pryrc$"
          "/\\(Gem\\|Cap\\|Vagrant\\|Rake\\|Pod\\|Puppet\\|Berks\\)file$")
@@ -13,6 +24,29 @@
   ;; Don't interfere with my custom RET behavior
   (define-key ruby-mode-map [?\n] nil)
 
+  ;; Version management with rbenv
+  (defun +ruby|add-version-to-modeline ()
+    "Add version string to the major mode in the modeline."
+    (setq mode-name
+          (if +python-current-version
+              (format "Ruby %s" +ruby-current-version)
+            "Ruby")))
+  (add-hook 'ruby-mode-hook #'+ruby|add-version-to-modeline)
+
+  (if (not (executable-find "rbenv"))
+      (setq +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 "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 'ruby-mode-hook #'+ruby|detect-rbenv-version))
+
   (map! :map ruby-mode-map
         :localleader
         :prefix "r"

modules/ui/doom-modeline/config.el

@@ -169,27 +169,6 @@ active."
   :group '+doom-modeline)
 
 
-;;
-;; Bootstrap
-;;
-
-;; Show version string for multi-version managers like rvm, rbenv, pyenv, etc.
-(defvar-local +doom-modeline-env-version nil)
-(defvar-local +doom-modeline-env-command nil)
-(add-hook! '(focus-in-hook find-file-hook) #'+doom-modeline|update-env)
-(defun +doom-modeline|update-env ()
-  (when +doom-modeline-env-command
-    (let* ((default-directory (doom-project-root))
-           (s (shell-command-to-string +doom-modeline-env-command)))
-      (setq +doom-modeline-env-version (if (string-match "[ \t\n\r]+\\'" s)
-                                           (replace-match "" t t s)
-                                         s)))))
-
-;; Only support python and ruby for now
-(add-hook! 'python-mode-hook (setq +doom-modeline-env-command "python --version 2>&1 | cut -d' ' -f2"))
-(add-hook! 'ruby-mode-hook   (setq +doom-modeline-env-command "ruby   --version 2>&1 | cut -d' ' -f2"))
-
-
 ;;
 ;; Modeline helpers
 ;;
@@ -388,8 +367,6 @@ directory, the file name, and its state (modified, read-only or non-existent)."
    (concat (format-mode-line mode-name)
            (when (stringp mode-line-process)
              mode-line-process)
-           (when +doom-modeline-env-version
-             (concat " " +doom-modeline-env-version))
            (and (featurep 'face-remap)
                 (/= text-scale-mode-amount 0)
                 (format " (%+d)" text-scale-mode-amount)))