ValueError: No semantic completer exists for filetypes: ['python']

[kgonidis]

Issue Prelude

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Issue Details

Provide a clear description of the problem, including the following key
questions:

• What did you do?

Include steps to reproduce here.

class TestClass( object ):
  def __init__( self, value ):
    self._var = value
    try:
      self.DoSomething()
    except ValueError:
      pass

  def DoSomething( self ):
    for i in range( 0, 100 ):
      if i < self._var:
        print( '{0} is less than the value'.format( i ) )
      else:
        print( '{0} might be more'.format( i ) )

    raise ValueError( 'Done' )

def Main():
  t = TestClass( 18 )
  t._var = 99
  t.DoSomething()

Main()

1. vim main.py
2. :YcmCompleter

Include description of a minimal test case, including any actual code required
to reproduce the issue.

If you made changes to vimrc_ycm_minimal, pase them here:

set nocp
set rtp+=~/.vim/bundle/YouCompleteMe
source ~/.vim/bundle/YouCompleteMe/plugin/youcompleteme.vim

• What did you expect to happen?

Include description of the expected behaviour.
Should get options to GoToDefinition, etc.

• What actually happened?
  ValueError: No semantic completer exists for filetypes: ['python']

Include description of the observed behaviour, including actual output,
screenshots, etc.

Diagnostic data

Output of vim --version

VIM - Vi IMproved 8.2 (2019 Dec 12, compiled Sep 27 2020 22:00:22)
Included patches: 1-1736
Compiled by kiron@kirontpad
Huge version with GTK2 GUI.  Features included (+) or not (-):
+acl               +cmdline_hist      +ex_extra          +jumplist          +mouse_dec         -perl              -sound             +textprop          +writebackup
+arabic            +cmdline_info      +extra_search      +keymap            -mouse_gpm         +persistent_undo   +spell             +timers            +X11
+autocmd           +comments          -farsi             +lambda            -mouse_jsbterm     +popupwin          +startuptime       +title             -xfontset
+autochdir         +conceal           +file_in_path      +langmap           +mouse_netterm     +postscript        +statusline        +toolbar           +xim
-autoservername    +cryptv            +find_in_path      +libcall           +mouse_sgr         +printer           -sun_workshop      +user_commands     -xpm
+balloon_eval      +cscope            +float             +linebreak         -mouse_sysmouse    +profile           +syntax            +vartabs           +xsmp_interact
+balloon_eval_term +cursorbind        +folding           +lispindent        +mouse_urxvt       -python            +tag_binary        +vertsplit         +xterm_clipboard
+browse            +cursorshape       -footer            +listcmds          +mouse_xterm       +python3           -tag_old_static    +virtualedit       -xterm_save
++builtin_terms    +dialog_con_gui    +fork()            +localmap          +multi_byte        +quickfix          -tag_any_white     +visual
+byte_offset       +diff              +gettext           -lua               +multi_lang        +reltime           -tcl               +visualextra
+channel           +digraphs          -hangul_input      +menu              -mzscheme          +rightleft         +termguicolors     +viminfo
+cindent           +dnd               +iconv             +mksession         +netbeans_intg     -ruby              +terminal          +vreplace
+clientserver      -ebcdic            +insert_expand     +modify_fname      +num64             +scrollbind        +terminfo          +wildignore
+clipboard         +emacs_tags        +ipv6              +mouse             +packages          +signs             +termresponse      +wildmenu
+cmdline_compl     +eval              +job               +mouseshape        +path_extra        +smartindent       +textobjects       +windows
   system vimrc file: "$VIM/vimrc"
     user vimrc file: "$HOME/.vimrc"
 2nd user vimrc file: "~/.vim/vimrc"
      user exrc file: "$HOME/.exrc"
  system gvimrc file: "$VIM/gvimrc"
    user gvimrc file: "$HOME/.gvimrc"
2nd user gvimrc file: "~/.vim/gvimrc"
       defaults file: "$VIMRUNTIME/defaults.vim"
    system menu file: "$VIMRUNTIME/menu.vim"
  fall-back for $VIM: "/usr/local/share/vim"
Compilation: gcc -c -I. -Iproto -DHAVE_CONFIG_H -DFEAT_GUI_GTK  -pthread -I/usr/include/gtk-2.0 -I/usr/lib/x86_64-linux-gnu/gtk-2.0/include -I/usr/include/gio-unix-2.0/ -I/u
sr/include/cairo -I/usr/include/pango-1.0 -I/usr/include/atk-1.0 -I/usr/include/cairo -I/usr/include/pixman-1 -I/usr/include/gdk-pixbuf-2.0 -I/usr/include/libpng16 -I/usr/in
clude/pango-1.0 -I/usr/include/harfbuzz -I/usr/include/pango-1.0 -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -I/usr/include/freetype2 -I/usr/include
/libpng16 -I/usr/include/freetype2 -I/usr/include/libpng16   -g -O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1
Linking: gcc   -L/usr/local/lib -Wl,--as-needed -o vim   -lgtk-x11-2.0 -lgdk-x11-2.0 -lpangocairo-1.0 -latk-1.0 -lcairo -lgdk_pixbuf-2.0 -lgio-2.0 -lpangoft2-1.0 -lpango-1.0
 -lgobject-2.0 -lglib-2.0 -lfontconfig -lfreetype -lSM -lICE -lXt -lX11 -lXdmcp -lSM -lICE  -lm -ltinfo   -ldl     -L/usr/lib/python3.6/config-3.6m-x86_64-linux-gnu -lpython
3.6m -lpthread -ldl -lutil -lm

Output of YcmDebugInfo

-- Resolve completions: Up front
-- Client logfile: /tmp/ycm_pkq1gbsj.log
-- Server Python interpreter: /usr/bin/python3
-- Server Python version: 3.6.9
-- Server has Clang support compiled in: True
-- Clang version: clang version 10.0.0 (https://github.com/ycm-core/llvm 038587147cf2f97d1c3e677042f69560c65b5bea)
-- No extra configuration file found
-- Server running at: http://127.0.0.1:37059
-- Server process ID: 13162
-- Server logfiles:
--   /tmp/ycmd_37059_stdout_xb3scfzq.log
--   /tmp/ycmd_37059_stderr_6bectkt7.log

Output of YcmDiags

Native filetype completion not supported for current file, cannot force recompilation.

Output of git rev-parse HEAD in YouCompleteMe installation directory

4891999f055167cf845671c231d7740c104074bd

Contents of YCM, ycmd and completion engine logfiles

Reproduce the issue with vim -Nu /path/to/YCM/vimrc_ycm_minimal, which
enabled debug logging and other useful diagnostics. Include a link to a
gist containing all of the log files listed by :YcmToggleLogs.
ycm_pkq1gbsj.log
ycmd_37059_stderr_6bectkt7.log
ycmd_37059_stdout_xb3scfzq.log

OS version, distribution, etc.

NAME="elementary OS"
VERSION="5.1.5 Hera"
ID=elementary
ID_LIKE=ubuntu
PRETTY_NAME="elementary OS 5.1.5 Hera"
LOGO=distributor-logo
VERSION_ID="5.1.5"
HOME_URL="https://elementary.io/"
SUPPORT_URL="https://elementary.io/support"
BUG_REPORT_URL="https://github.com/elementary/os/issues/new"
PRIVACY_POLICY_URL="https://elementary.io/privacy-policy"
VERSION_CODENAME=hera
UBUNTU_CODENAME=bionic

Include system information here.

Output of build/install commands

Include link to a gist containing the invocation and entire output of
install.py if reporting an installation issue.

[puremourning]

I think this might be related to/dup of: #3765

We have this in the FAQ:

https://github.com/ycm-core/YouCompleteMe/wiki/FAQ#after-updating-python-completion-no-longer-works

Which you would have seen, according to:

[ x] I have read and understood YCM's README, especially the Frequently Asked Questions section.

[kgonidis]

Thanks @puremourning. I did try the reinstall from:
after-updating-python-completion-no-longer-works
That didn't work but I just tried the more adventurous solution and that worked. Thanks for your help!

[puremourning]

I've updated the comment to just say delete the pyc files thanks..