lang/python: add support for more env managers

+ Rewritten +conda support
+ Adds +pyenv and +pyvenv flags with support.
+ New +ipython flag to enable ipython REPL support
+ Added pipenv support. This is the new default, instead of pyenv, and
  isn't hidden behind a module flag because it is officially endorsed by
  python.

Addresses #736

modules/lang/python/config.el

@@ -1,14 +1,9 @@
 ;;; 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.")
+(defvar +python-mode-name-functions '(+python-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 python-mode
+`mode-name' and displayed in the mode-line.")
 
 
 ;;
@@ -22,7 +17,7 @@ is loaded.")
         python-indent-guess-indent-offset-verbose nil
         python-shell-interpreter "python")
   :config
-  (set-env! "PYTHONPATH" "PYENV_ROOT")
+  (set-env! "PYTHONPATH" "PYENV")
   (set-electric! 'python-mode :chars '(?:))
   (set-repl-handler! 'python-mode #'+python/repl)
 
@@ -44,7 +39,11 @@ is loaded.")
     :for "for"
     :return "return" :yield "yield")
 
-  (when (executable-find "ipython")
+  (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)))
+
+  (when (featurep! +ipython)
     (setq python-shell-interpreter "ipython"
           python-shell-interpreter-args "-i --simple-prompt --no-color-info"
           python-shell-prompt-regexp "In \\[[0-9]+\\]: "
@@ -55,45 +54,21 @@ is loaded.")
           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)
+          (if-let* ((result (run-hook-with-args-until-success '+python-mode-name-functions)))
+              (format "Python %s" result)
             "Python")))
-  (add-hook 'python-mode-hook #'+python|add-version-to-modeline)
-
-  (if (not (executable-find "pyenv"))
-      (setq-default +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 "PYENV_VERSION= 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))))
+  (add-hook 'python-mode-hook #'+python|add-version-to-modeline))
 
 
 (def-package! anaconda-mode
-  :after python
+  :hook python-mode
   :init
   (setq anaconda-mode-installation-directory (concat doom-etc-dir "anaconda/")
         anaconda-mode-eldoc-as-single-line t)
   :config
-  (add-hook 'python-mode-hook #'anaconda-mode)
   (add-hook 'anaconda-mode-hook #'anaconda-eldoc-mode)
   (set-company-backend! 'python-mode '(company-anaconda))
   (set-popup-rule! "^\\*anaconda-mode" :select nil)
@@ -111,6 +86,8 @@ environment variables."
   (add-hook! 'python-mode-hook
     (add-hook 'kill-buffer-hook #'+python|auto-kill-anaconda-processes nil t))
 
+  (when (featurep 'evil)
+    (add-hook 'anaconda-mode-hook #'evil-normalize-keymaps))
   (map! :map anaconda-mode-map
         :localleader
         :prefix "f"
@@ -123,13 +100,14 @@ environment variables."
 
 (def-package! nose
   :commands nose-mode
-  :preface
-  (defvar nose-mode-map (make-sparse-keymap))
-  :init
-  (associate! nose-mode :match "/test_.+\\.py$" :modes (python-mode))
+  :preface (defvar nose-mode-map (make-sparse-keymap))
+  :init (associate! nose-mode :match "/test_.+\\.py$" :modes (python-mode))
   :config
   (set-popup-rule! "^\\*nosetests" :size 0.4 :select nil)
   (set-yas-minor-mode! 'nose-mode)
+  (when (featurep 'evil)
+    (add-hook 'nose-mode-hook #'evil-normalize-keymaps))
+
   (map! :map nose-mode-map
         :localleader
         :prefix "t"
@@ -143,9 +121,59 @@ environment variables."
 
 
 ;;
-;; Evil integration
+;; Environment management
 ;;
 
-(when (featurep! :feature evil +everywhere)
-  (add-hook! '(anaconda-mode-hook nose-mode-hook)
-    #'evil-normalize-keymaps))
+(def-package! pipenv
+  :commands pipenv-project-p
+  :hook (python-mode . pipenv-mode))
+
+
+(def-package! pyenv-mode
+  :when (featurep! +pyenv)
+  :after python
+  :config
+  (pyenv-mode +1)
+  (add-to-list '+python-mode-name-functions #'pyenv-mode-version nil #'eq))
+
+
+(def-package! pyvenv
+  :when (featurep! +pyvenv)
+  :after python
+  :config
+  (defun +python-current-pyvenv () pyvenv-virtual-env-name)
+  (add-to-list '+python-mode-name-functions #'+python-current-pyvenv nil #'eq))
+
+
+(def-package! conda
+  :when (featurep! +conda)
+  :after python
+  :config
+  ;; Adds conda support to Doom Emacs. `conda-anaconda-home' should be the path
+  ;; to your anaconda installation, and will be guessed from the following:
+  ;;
+  ;; + ~/.anaconda3
+  ;; + ~/.anaconda
+  ;; + ~/.miniconda
+  ;; + ~/usr/bin/anaconda3
+  ;;
+  ;; If none of these work, you'll need to set `conda-anaconda-home' yourself.
+  ;;
+  ;; Once set, run M-x `conda-env-activate' to switch between environments OR
+  ;; turn on `conda-env-autoactivate-mode' if you want it done automatically.
+  (unless (cl-loop for dir in (list conda-anaconda-home
+                                    "~/.anaconda"
+                                    "~/.miniconda"
+                                    "/usr/bin/anaconda3")
+                   if (file-directory-p dir)
+                   return (setq conda-anaconda-home dir
+                                conda-env-home-directory dir))
+    (message "Cannot find Anaconda installation"))
+
+  ;; integration with term/eshell
+  (conda-env-initialize-interactive-shells)
+  (after! eshell (conda-env-initialize-eshell))
+
+  (add-to-list '+python-mode-name-functions #'+python-conda-env nil #'eq)
+
+  (advice-add 'anaconda-mode-bootstrap :override #'+python*anaconda-mode-bootstrap-in-remote-environments))