Vim: Make hlsearch work with :s, :g, :v, ...

[Symaxion]

Describe the bug
If you enable hlsearch and use the / command, it will highlight the matches of your search as you type.

With actual Vim, this also works with the search query of the :g/, :v/ and :s// commands (and maybe some other ones that I missed?). VsCodeVim does not support hlsearch for these commands.

To Reproduce
Steps to reproduce the behaviour:

1. In settings.json, set the vim.hlsearch option to true.
2. Enter the following text into an empty document:
   ```
   foo
   bar
   foobar
3. Type the following in command mode: :s/foo

Expected behaviour
The matches in the document get highlighted as you type, same as if you typed /foo.

Screenshots
N/A

Environment (please complete the following information):

• Extension (VsCodeVim) version: 1.14.5
• VSCode version: 1.45.1
• OS: macOS Mojave 10.14.6

Additional context
N/A

[J-Fields]

What version of vim can you reproduce this on, and with what settings?

[Symaxion]

It seems that both hlsearch and incsearch need to be enabled for Vim to exhibit this exact behaviour.

I can get it to reproduce in Vim (with vim -u NONE) just by setting :set hlsearch and :set incsearch.

:version
VIM - Vi IMproved 8.2 (2019 Dec 12, compiled Apr 12 2020 00:47:07)
macOS version
Included patches: 1-539
Compiled by [email protected]
Huge version with MacVim GUI.  Features included (+) or not (-):
+acl               +cindent           +cursorshape       +file_in_path      +job               +menu              +mouse_urxvt       +persistent_undo   +scrollbind        -tag_any_white     +transparency      +windows
+arabic            +clientserver      +dialog_con_gui    +find_in_path      +jumplist          +mksession         +mouse_xterm       +popupwin          +signs             -tcl               +user_commands     +writebackup
+autocmd           +clipboard         +diff              +float             +keymap            +modify_fname      +multi_byte        +postscript        +smartindent       +termguicolors     +vartabs           -X11
+autochdir         +cmdline_compl     +digraphs          +folding           +lambda            +mouse             +multi_lang        +printer           -sound             +terminal          +vertsplit         -xfontset
-autoservername    +cmdline_hist      +dnd               -footer            +langmap           +mouseshape        -mzscheme          +profile           +spell             +terminfo          +virtualedit       +xim
+balloon_eval      +cmdline_info      -ebcdic            +fork()            +libcall           +mouse_dec         +netbeans_intg     +python/dyn        +startuptime       +termresponse      +visual            -xpm
+balloon_eval_term +comments          +emacs_tags        +fullscreen        +linebreak         -mouse_gpm         +num64             +python3/dyn       +statusline        +textobjects       +visualextra       -xsmp
+browse            +conceal           +eval              -gettext           +lispindent        -mouse_jsbterm     +odbeditor         +quickfix          -sun_workshop      +textprop          +viminfo           -xterm_clipboard
++builtin_terms    +cryptv            +ex_extra          -hangul_input      +listcmds          +mouse_netterm     +packages          +reltime           +syntax            +timers            +vreplace          -xterm_save
+byte_offset       +cscope            +extra_search      +iconv             +localmap          +mouse_sgr         +path_extra        +rightleft         +tag_binary        +title             +wildignore
+channel           +cursorbind        -farsi             +insert_expand     +lua/dyn           -mouse_sysmouse    +perl/dyn          +ruby/dyn          -tag_old_static    +toolbar           +wildmenu
   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: "/Applications/MacVim.app/Contents/Resources/vim"
Compilation: clang -c -I. -Iproto -DHAVE_CONFIG_H -DFEAT_GUI_MACVIM -Wall -Wno-unknown-pragmas -pipe  -DMACOS_X -DMACOS_X_DARWIN  -g -O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1
Linking: clang   -L. -fstack-protector-strong -L/usr/local/lib -L/usr/local/opt/libyaml/lib -L/usr/local/opt/[email protected]/lib -L/usr/local/opt/readline/lib -L. -fstack-protector-strong -L/usr/local/lib -L/usr/local/opt/libyaml/lib -L/usr/l
ocal/opt/[email protected]/lib -L/usr/local/opt/readline/lib  -L/usr/local/lib -o Vim -framework Cocoa -framework Carbon       -lm  -lncurses -liconv -framework AppKit   -fstack-protector  -L/System/Library/Perl/5.18/darwin-thread-multi-2level/
CORE

[J-Fields]

Ah, of course it only highlights those within the line range specified (so :%s/... will highlight all occurrences). Yeah this would be a great feature to implement.

[J-Fields]

Related: inccommand, hs-Substitute