semantic layer causing python layer to die in `develop`

[deybhayden]

I have both semantic & python layers enabled on develop (commit 1d1772b8548cd744ac97189c8a2acb08fb263be5) and I get the below error when opening a Python file (for the first time in an Emacs session)

Debugger entered--Lisp error: (error "Selecting deleted buffer")
  semantic-mode(1)
  (lambda nil (require (quote semantic)) (add-to-list (quote semantic-default-submodes) (quote global-semantic-stickyfunc-mode)) (add-to-list (quote semantic-default-submodes) (quote global-semantic-idle-summary-mode)) (if (eq major-mode (quote emacs-lisp-mode)) (progn (semantic-default-elisp-setup))) (semantic-mode 1))()
  run-hooks(change-major-mode-after-body-hook prog-mode-hook python-mode-hook)
  apply(run-hooks (change-major-mode-after-body-hook prog-mode-hook python-mode-hook))
  run-mode-hooks(python-mode-hook)
  python-mode()
  set-auto-mode-0(python-mode nil)
  set-auto-mode()
  normal-mode(t)
  after-find-file(nil t)

Disabling the semantic layer allows me to open up Python files without an error.

[tuhdo]

I cannot reproduce. What's your Emacs version? Can you reproduce it with just semantic and python layer included (aside from the default layers)?

[deybhayden]

Version: GNU Emacs 24.5.1 (x86_64-apple-darwin14.1.0, Carbon Version 157 AppKit 1344.72) of 2015-05-05

I can not reproduce it with only those layers enabled only. The list of layers that I also had active:

     auto-completion
     semantic
     better-defaults
     themes-megapack
     (git :variables
          git-magit-status-fullscreen t
          git-enable-github-support t
          git-gutter-use-fringe t)
     (syntax-checking :variables
                      syntax-checking-enable-tooltips nil)
     osx
     ;; Language support
     markdown
     javascript
     html
     go
     shell-scripts
     dockerfile
     puppet
     salt

After I reloaded Emacs with everything 180 some odd packages being removed & reinstalled - I don't have this issue anymore. I don't know if some package was out of date and I missed it, but working now. :+1:

[deybhayden]

Aha - I remembered I added this line:

  (add-hook 'prog-mode-hook 'semantic-mode)

to my dotspacemacs/config function, and when I took it back out, the issue started happening again. It doesn't happen, when I leave it. I doubt that's intended?

[tuhdo]

I have no such line and everything is working fine for me, and that is with or without Python layer. You don't need to add such line because when you add semantic layer, it already added that.

[deybhayden]

I can provide my entire .spacemacs file if you want, but I've tracked it down to the git layer. If i don't enable it, I don't get the error.

[deybhayden]

Confirmed - If i just enable, semantic, python, and git layers, I get the specified error.

   dotspacemacs-configuration-layers
   '(
     ;; auto-completion
     semantic
     ;; better-defaults
     (git :variables
          git-magit-status-fullscreen t
          git-enable-github-support t
          git-gutter-use-fringe t)
     ;; (syntax-checking :variables
     ;;                  syntax-checking-enable-tooltips nil)
     ;; osx
     ;; edit-server
     ;; Language support
     ;; markdown
     python
     ;; javascript
     ;; html
     ;; go
     ;; shell-scripts
     ;; dockerfile
     ;; puppet
     ;; salt
     )

[tuhdo]

I also enable git layer, but only this much:

(git :variables
      git-enable-github-support t
      git-gutter-use-fringe t)

[deybhayden]

I get the error with this exact ~/.spacemacs config:

;; -*- mode: dotspacemacs -*-
;; This file is loaded by Spacemacs at startup.
;; It must be stored in your home directory.

(defun dotspacemacs/layers ()
  "Configuration Layers declaration."
  (setq-default
   ;; List of additional paths where to look for configuration layers.
   ;; Paths must have a trailing slash (ie. `~/.mycontribs/')
   dotspacemacs-configuration-layer-path '()
   ;; List of configuration layers to load. If it is the symbol `all' instead
   ;; of a list then all discovered layers will be installed.
   dotspacemacs-configuration-layers
   '(
     semantic
     (git :variables
          git-enable-github-support t
          git-gutter-use-fringe t)
     python
     )
   ;; A list of packages and/or extensions that will not be install and loaded.
   dotspacemacs-excluded-packages '()
   ;; If non-nil spacemacs will delete any orphan packages, i.e. packages that
   ;; are declared in a layer which is not a member of
   ;; the list `dotspacemacs-configuration-layers'
   dotspacemacs-delete-orphan-packages t))

(defun dotspacemacs/init ()
  "Initialization function.
This function is called at the very startup of Spacemacs initialization
before layers configuration."
  ;; This setq-default sexp is an exhaustive list of all the supported
  ;; spacemacs settings.
  (setq-default
   ;; Either `vim' or `emacs'. Evil is always enabled but if the variable
   ;; is `emacs' then the `holy-mode' is enabled at startup.
   dotspacemacs-editing-style 'vim
   ;; If non nil output loading progess in `*Messages*' buffer.
   dotspacemacs-verbose-loading nil
   ;; Specify the startup banner. Default value is `official', it displays
   ;; the official spacemacs logo. An integer value is the index of text
   ;; banner, `random' chooses a random text banner in `core/banners'
   ;; directory. A string value must be a path to a .PNG file.
   ;; If the value is nil then no banner is displayed.
   ;; dotspacemacs-startup-banner 'official
   dotspacemacs-startup-banner 'official
   ;; t if you always want to see the changelog at startup
   dotspacemacs-always-show-changelog t
   ;; List of items to show in the startup buffer. If nil it is disabled.
   ;; Possible values are: `recents' `bookmarks' `projects'."
   dotspacemacs-startup-lists '(recents projects)
   ;; List of themes, the first of the list is loaded when spacemacs starts.
   ;; Press <SPC> T n to cycle to the next theme in the list (works great
   ;; with 2 themes variants, one dark and one light)
   dotspacemacs-themes '(smyx)
   ;; If non nil the cursor color matches the state color.
   dotspacemacs-colorize-cursor-according-to-state t
   ;; Default font. `powerline-scale' allows to quickly tweak the mode-line
   ;; size to make separators look not too crappy.
   dotspacemacs-default-font '("Source Code Pro"
                               :size 12
                               :weight normal
                               :width normal
                               :powerline-scale 1.1)
   ;; The leader key
   dotspacemacs-leader-key "SPC"
   ;; The leader key accessible in `emacs state' and `insert state'
   dotspacemacs-emacs-leader-key "M-m"
   ;; Major mode leader key is a shortcut key which is the equivalent of
   ;; pressing `<leader> m`. Set it to `nil` to disable it.
   dotspacemacs-major-mode-leader-key ","
   ;; Major mode leader key accessible in `emacs state' and `insert state'
   dotspacemacs-major-mode-emacs-leader-key "C-M-m"
   ;; The command key used for Evil commands (ex-commands) and
   ;; Emacs commands (M-x).
   ;; By default the command key is `:' so ex-commands are executed like in Vim
   ;; with `:' and Emacs commands are executed with `<leader> :'.
   dotspacemacs-command-key ":"
   ;; If non nil the paste micro-state is enabled. While enabled pressing `p`
   ;; several times cycle between the kill ring content.
   dotspacemacs-enable-paste-micro-state t
   ;; Guide-key delay in seconds. The Guide-key is the popup buffer listing
   ;; the commands bound to the current keystrokes.
   dotspacemacs-guide-key-delay 0.4
   ;; If non nil a progress bar is displayed when spacemacs is loading. This
   ;; may increase the boot time on some systems and emacs builds, set it to
   ;; nil ;; to boost the loading time.
   dotspacemacs-loading-progress-bar t
   ;; If non nil the frame is fullscreen when Emacs starts up.
   ;; (Emacs 24.4+ only)
   dotspacemacs-fullscreen-at-startup nil
   ;; If non nil `spacemacs/toggle-fullscreen' will not use native fullscreen.
   ;; Use to disable fullscreen animations in OSX."
   dotspacemacs-fullscreen-use-non-native nil
   ;; If non nil the frame is maximized when Emacs starts up.
   ;; Takes effect only if `dotspacemacs-fullscreen-at-startup' is nil.
   ;; (Emacs 24.4+ only)
   dotspacemacs-maximized-at-startup nil
   ;; A value from the range (0..100), in increasing opacity, which describes
   ;; the transparency level of a frame when it's active or selected.
   ;; Transparency can be toggled through `toggle-transparency'.
   dotspacemacs-active-transparency 90
   ;; A value from the range (0..100), in increasing opacity, which describes
   ;; the transparency level of a frame when it's inactive or deselected.
   ;; Transparency can be toggled through `toggle-transparency'.
   dotspacemacs-inactive-transparency 90
   ;; If non nil unicode symbols are displayed in the mode line.
   dotspacemacs-mode-line-unicode-symbols t
   ;; If non nil smooth scrolling (native-scrolling) is enabled. Smooth
   ;; scrolling overrides the default behavior of Emacs which recenters the
   ;; point when it reaches the top or bottom of the screen.
   dotspacemacs-smooth-scrolling t
   ;; If non-nil smartparens-strict-mode will be enabled in programming modes.
   dotspacemacs-smartparens-strict-mode nil
   ;; If non nil advises quit functions to keep server open when quitting.
   dotspacemacs-persistent-server nil
   ;; List of search tool executable names. Spacemacs uses the first installed
   ;; tool of the list. Supported tools are `ag', `pt', `ack' and `grep'.
   dotspacemacs-search-tools '("ag" "grep")
   ;; The default package repository used if no explicit repository has been
   ;; specified with an installed package.
   ;; Not used for now.
   dotspacemacs-default-package-repository nil
   )
  )

(defun dotspacemacs/config ()
  "Configuration function.
 This function is called at the very end of Spacemacs initialization after
layers configuration."
  )

;; Do not write anything past this comment. This is where Emacs will
;; auto-generate custom variable definitions.

[deybhayden]

I get the error even after removing ~/.emacs.d/(.cache | elpa | semanticdb).

[syl20bnr]

Thanks for all the info. I narrowed it down to git-gutter package but cannot allocate more time on this problem for now.

[syl20bnr]

To completely remove git-gutter you have to set git-gutter-use-fringe to nil or remove it from your dotfile and add git-gutter to dotspacemacs-excluded-packages.

[TheBB]

Since git-gutter has been removed, this is presumably fixed.