neotree won't show help under Emacs style key-binding

[asdfasdfasdfasdf4]

Description: Neotree will prompt "Cannot make side window the only window" and no hot-key help shows up when "?" is pressed under Emacs style key binding, where Vim style key-binding works perfectly, does shows the help prompt.

Reproduction Guide (The problem): 1) set dotspacemacs to emacs style key-binding 2) Start spacemacs "M-x neotree" 3) In the neotree side window press "?"

Observed Behaviour: Will prompt "Cannot make side window the only window"

Expected Behaviour: Shows a new window above the mini-buffer on short-cuts for neotree. Under Vim style key-binding, the help window does appear.

System Info :computer:

• OS: gnu/linux (Linuxmint 17)
• Emacs: 25.1.1
• Spacemacs: 0.200.5
• Spacemacs branch: master (rev. 664ba6a)
• Graphic display: t
• Distribution: spacemacs
• Editing style: emacs
• Completion: helm
• Layers:

  (python helm auto-completion emacs-lisp spell-checking syntax-checking)

[bmag]

Using develop branch, I had to disable purpose-mode to be able to reproduce the error. Here's the backtrace:

Debugger entered--Lisp error: (error "Cannot make side window the only window")
  signal(error ("Cannot make side window the only window"))
  error("Cannot make side window the only window")
  delete-other-windows(#<window 550 on  *NeoTree*>)
  #[(&rest --cl-rest--) "\203\f [ ... snipped byte-code ...]
  apply(#[(&rest --cl-rest--) "\203\f [ ... snipped byte-code ...]
  ad-Advice-popwin:create-popup-window(#[(&rest --cl-rest--) "\203\f [ ... snipped byte-code ...]
  apply(ad-Advice-popwin:create-popup-window #[(&rest --cl-rest--) "\203\f [ ... snipped byte-code ...]
  popwin:create-popup-window(0.4 bottom t)
  popwin:popup-buffer(#<buffer *Help*> :width 30 :height 0.4 :position bottom :noselect t :dedicated t :stick t :tail nil)
  popwin:display-buffer-1(#<buffer *Help*> :if-config-not-found #[(buffer) "\302   \"\207" [buffer not-this-window popwin:original-display-buffer] 3])
  popwin:display-buffer(#<buffer *Help*> nil)
  popwin:display-buffer-action(#<buffer *Help*> nil)
  display-buffer(#<buffer *Help*> nil)
  temp-buffer-window-show(#<buffer *Help*> nil)
  describe-mode()
  funcall-interactively(describe-mode)
  call-interactively(describe-mode nil nil)
  command-execute(describe-mode)

Apparently, popwin doesn't handle side windows correctly, and neotree had become a real side window (from a technical perspective) a few months ago. This probably reproduces with stock Emacs, Neotree and Popwin, so I suggest you report it upstream to Popwin

[bmag]

For anyone wondering, this only happens for Emacs editing style, because in Hybrid and Vim editing styles a transient state is used instead of calling describe-mode.

[feluxe]

I get the same error when I open Neotree and try to create a new file: SPC-f-T c

Cannot make side window the only window.

I'm using Vim editing style.

[bmag]

@feluxe that's a different upstream issue, see https://github.com/jaypei/emacs-neotree/issues/226

[clm84]

Related issue I think: when trying to delete multiple buffers from IBuffer while neotree is open on the side, I get:

Cannot split side window or parent window of side window

[oracleyue]

I confirm the bug pointed by @bmag : it is due to popwin. Once I turn off the popwin mode, it will work fine.

[stradicat]

I confirm the bug pointed by @bmag : it is due to popwin. Once I turn off the popwin mode, it will work fine.

This worked for me too.

Proposed solutions in NeoTree did not.

[github-actions[bot]]

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