install.py now fails with python 3.8.10 (Ubuntu 20.04) over argparse.BooleanOptionalAction

[Halfwalker]

Issue Prelude

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Issue Details

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

• What did you do?
  Attempted to compile YCM under Ubuntu 20.04 with python3 v3.8.10

Include steps to reproduce here.

1. YCM installed into ~/.vim/bundle/YouCompleteMe via Vundle
2. cd ~/.vim/bundle/YouCompeteMe
3. python3 install.py --clangd-completer

If you made changes to vimrc_ycm_minimal, pase them here:

N/A

• What did you expect to happen?
  YCM to compile cleanly

• What actually happened?
  Compile failed with

  AttributeError: module 'argparse' has no attribute 'BooleanOptionalAction'
  

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

root@5ca634ec9adf:/home/testing/.vim/bundle/YouCompleteMe# python3 --version
Python 3.8.10

Compile

root@5ca634ec9adf:/home/testing/.vim/bundle/YouCompleteMe# python3 install.py --clangd-completer
Traceback (most recent call last):
  File "/home/testing/.vim/bundle/YouCompleteMe/third_party/ycmd/build.py", line 1373, in <module>
    Main()
  File "/home/testing/.vim/bundle/YouCompleteMe/third_party/ycmd/build.py", line 1333, in Main
    args = ParseArguments()
  File "/home/testing/.vim/bundle/YouCompleteMe/third_party/ycmd/build.py", line 571, in ParseArguments
    parser.add_argument( '--regex', action = argparse.BooleanOptionalAction,
AttributeError: module 'argparse' has no attribute 'BooleanOptionalAction'

Diagnostic data

Output of vim --version

root@5ca634ec9adf:/home/testing/.vim/bundle/YouCompleteMe# vim --version
VIM - Vi IMproved 9.1 (2024 Jan 02, compiled Dec 19 2024 01:10:53)
Included patches: 1-945
Compiled by runner@fv-az2030-601
Huge version without GUI.  Features included (+) or not (-):
+acl               +file_in_path      +mouse_urxvt       -tag_any_white
+arabic            +find_in_path      +mouse_xterm       +tcl
+autocmd           +float             +multi_byte        +termguicolors
+autochdir         +folding           +multi_lang        +terminal
-autoservername    -footer            -mzscheme          +terminfo
-balloon_eval      +fork()            +netbeans_intg     +termresponse
+balloon_eval_term +gettext           +num64             +textobjects
-browse            -hangul_input      +packages          +textprop
++builtin_terms    +iconv             +path_extra        +timers
+byte_offset       +insert_expand     +perl              +title
+channel           +ipv6              +persistent_undo   -toolbar
+cindent           +job               +popupwin          +user_commands
-clientserver      +jumplist          +postscript        +vartabs
-clipboard         +keymap            +printer           +vertsplit
+cmdline_compl     +lambda            +profile           +vim9script
+cmdline_hist      +langmap           +python/dyn        +viminfo
+cmdline_info      +libcall           +python3/dyn       +virtualedit
+comments          +linebreak         +quickfix          +visual
+conceal           +lispindent        +reltime           +visualextra
+cryptv            +listcmds          +rightleft         +vreplace
+cscope            +localmap          +ruby              +wildignore
+cursorbind        +lua               +scrollbind        +wildmenu
+cursorshape       +menu              +signs             +windows
+dialog_con        +mksession         +smartindent       +writebackup
+diff              +modify_fname      +sodium            -X11
+digraphs          +mouse             +sound             +xattr
-dnd               -mouseshape        +spell             -xfontset
-ebcdic            +mouse_dec         +startuptime       -xim
+emacs_tags        -mouse_gpm         +statusline        -xpm
+eval              -mouse_jsbterm     -sun_workshop      -xsmp
+ex_extra          +mouse_netterm     +syntax            -xterm_clipboard
+extra_search      +mouse_sgr         +tag_binary        -xterm_save
-farsi             -mouse_sysmouse    -tag_old_static
   system vimrc file: "$VIM/vimrc"
     user vimrc file: "$HOME/.vimrc"
 2nd user vimrc file: "~/.vim/vimrc"
 3rd user vimrc file: "~/.config/vim/vimrc"
      user exrc file: "$HOME/.exrc"
       defaults file: "$VIMRUNTIME/defaults.vim"
  fall-back for $VIM: "/usr/share/vim"
Compilation: gcc-10 -c -I. -Iproto -DHAVE_CONFIG_H -Wno-deprecated-declarations -D_REENTRANT -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1
Linking: gcc-10 -Wl,-E -L/usr/local/lib -Wl,--as-needed -o vim -lm -ltinfo -lselinux -L/usr/lib/x86_64-linux-gnu -lcanberra -L/usr/lib/x86_64-linux-gnu -lsodium -ldl -L/usr/lib -llua5.3 -Wl,-E -fstack-protector-strong -L/usr/local/lib -L/usr/lib/x86_64-linux-gnu/perl/5.30/CORE -lperl -ldl -lm -lpthread -lcrypt -L/usr/lib/x86_64-linux-gnu -ltcl8.6 -ldl -lz -lpthread -lm -lruby-2.7 -lm -L/usr/lib

Output of YcmDebugInfo

N/A

Output of YcmDiags

N/A

Output of git rev-parse HEAD in YouCompleteMe installation directory

root@5ca634ec9adf:/home/testing/.vim/bundle/YouCompleteMe# git rev-parse HEAD
131b1827354871a4e984c1660b6af0fefca755c3

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.

OS version, distribution, etc.

Include system information here.
Ubuntu 20.04
Python3 v3.8.10

Output of build/install commands

See above

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

[bstaletic]

We usually make sure that the latest Ubuntu LTS works out of the box. Ubuntu 20.04 is two LTS releases behind.
We also support old python versions until they go EOL. Python 3.8 reached its extended EOL 2 months ago.

I do realize we did not update our documentation to reflect the requirement for python 3.9.
The commit that introduced BooleanOptionalAction was 19fa3c8

My recommendation to you would be to install a newer python, though. If 3.9 isn't packaged by ubuntu 20.04, you should be able to add the deadsnakes PPA.

[Halfwalker]

Easy enough to add 3.9, though python being python ... :P Was thinking perhaps there was gating around the BooleanOptionalAction that might have been missed somewhere