How I almost added RHS info to git-bash, in /.config/git/git-prompt.sh

git-prompt.sh

# ----------------------------------------------------------------
#  prompt config for (git-)bash
# this is called from /etc/profile.d/git-prompt.sh 
# 	(if this file exists, which it apparently does, since you are reading it...)
# src: https://github.com/git-for-windows/build-extra/blob/main/git-extra/git-prompt.sh
# 
# why this file? /etc/profile.d/git-prompt.sh is overwritten with git (for windows) is updated.
# starting point (default setup for the prompt) can be found in /etc/profile.d/git-prompt.sh 
# 
# Config info: https://gist.github.com/adojos/fd30baa716dbfbe282fe147ab717b664
# edits: 
# terminal window, commented newline and out all of "line 2", just keeping prompt character


# ----------------------------------------------------------------
# src: https://stackoverflow.com/a/43729966/3701019
#
# Right hand side of prompt
#
# Select git info displayed, see /usr/lib/git-core/git-sh-prompt for more
# export GIT_PS1_SHOWCOLORHINTS=1           # Make pretty colours inside $PS1
# export GIT_PS1_SHOWDIRTYSTATE=1           # '*'=unstaged, '+'=staged
# export GIT_PS1_SHOWSTASHSTATE=1           # '$'=stashed
# export GIT_PS1_SHOWUNTRACKEDFILES=1       # '%'=untracked
# export GIT_PS1_SHOWUPSTREAM="verbose"     # 'u='=no difference, 'u+1'=ahead by 1 commit
# export GIT_PS1_STATESEPARATOR=''          # No space between branch and index status
# export GIT_PS1_DESCRIBE_STYLE="describe"  # Detached HEAD style:
#  describe      relative to older annotated tag (v1.6.3.1-13-gdd42c2f)
#  contains      relative to newer annotated tag (v1.6.3.2~35)
#  branch        relative to newer tag or branch (master~4)
#  default       exactly eatching tag

# Sets prompt like:
# ravi@boxy:~/prj/sample_app[exit]$                   master*% u= | 30 Apr 22:27
function _set_bash_prompt() {
  # Set left hand side of the prompt
  # PS1="\u@\h:\w\$ "

  #
  # Git status
  #

  # Save current state of user shopt settings promptvars and extglob
  local user_shopt
  user_shopt=$(shopt -p promptvars extglob)
  # __git_ps1 usually returns literal text "${__git_ps1_branch_name}" rather
  # than the contained branch name, eg "master". This prevents calculating
  # the length of the printable characers in the RHS string (used to move the
  # cursor that many columns left from the terminal's right edge.) However if
  # "shopt promptvars" is unset, __git_ps1 it will include the dereferenced
  # branch name instead.
  shopt -qu promptvars
  # extglob is required for the ${variable//@(pattern)/} replacements
  shopt -qs extglob

  # Allow disabling git status and no error if __git_ps1 undefined
  if [[ ! -v _disable_git_prompt && $(type -t __git_ps1 2>/dev/null) == function ]]; then
    # __git_ps1 will only make pretty colours inside $PS1
    local old_PS1=$PS1
    __git_ps1 "" "" "%s" # force colour; no default round bracket (decorations)

    # Strip "\[" and "\[": non-printable character markers. __git_ps1 outputs
    # them however the whole of the RHS prompt needs to be included in these
    # markers, and they can't be nested.
    git=${PS1//@(\\@(\[|\]))/}
    PS1=$old_PS1
  fi

  #
  # Right hand side of prompt
  #
  local rhs="" # String to be printed on the right hand side of terminal

  # Create a string like: "25 Apr 13:15"
  local date_time
  printf -v date_time "%(%e %b %H:%M)T" -1 # -1 is current time

  # Format the RHS prompt
  [[ -n $git ]] && rhs="$git | " #"
  rhs+="\e[0;1;31m${date_time}"

  # Strip ANSI CSI commands (eg colours) to enble counting the length of
  # printable characters, giving offset of cursor from terminal RHS edge (from
  # https://www.commandlinefu.com/commands/view/12043/remove-color-special-escape-ansi-codes-from-text-with-sed)
  # Neither bash not sed support lookbehind zero-length assertions, so it's not
  # possible to ignore "\\e", (ie a literal '\' followed by a literal 'e'), yet
  # still remove "\e" (ie ESC)
  local rhs_printable=${rhs//@(\\@(\[|]|[Ee]\[*([0-9;])[a-zA-Z]))/}
  # or, in using sed (but requires exec):
  # local rhs_printable=$(sed -e 's,\\[][]\|\\[Ee]\[\([0-9;]\)*[A-Za-z],,g' <<< "$rhs")

  # Reference: https://en.wikipedia.org/wiki/ANSI_escape_code
  local Save='\e[s' # Save cursor position
  local Rest='\e[u' # Restore cursor to save point

  # Save cursor position, jump to (right hand edge minus N columns) where N is
  # the length of the printable RHS string. Print the RHS string, then return
  # to the saved position and print the LHS prompt.

  # Note: "\[" and "\]" are used so that bash can calculate the number of
  # printed characters so that the prompt doesn't do strange things when
  # command line editing/browsing/completion. Ensure that these are not nested.
  PS1="\[\e[0m${Save}\e[$((COLUMNS - ${#rhs_printable}))G${rhs}${Rest}\]${PS1}"

  eval "$user_shopt"
}
export -f _set_bash_prompt
# eval "$_options"; unset _options # Restore previous shell options from line 2


# ----------------------------------------------------------------
# This section is based on git-prompt.sh:
# 
PS1='\[\033]0;${TITLEPREFIX}\W  `__git_ps1`   [  \D{%H:%M  - %a %d %b}  ]\007\]' # set window title
# PS1="$PS1"'\n'                 # new line
# PS1="$PS1"'\[\033[32m\]'       # change to green
# PS1="$PS1"'\u@\h '             # user@host<space>
# PS1="$PS1"'\[\033[35m\]'       # change to purple
# PS1="$PS1"'$MSYSTEM '          # show MSYSTEM
# PS1="$PS1"'\[\033[33m\]'       # change to brownish yellow
# PS1="$PS1"'\w'                 # current working directory
if test -z "$WINELOADERNOEXEC" # this cannot be commented out, since this part (1) sets up git cli and (2) prompt. 
then
	GIT_EXEC_PATH="$(git --exec-path 2>/dev/null)"
	COMPLETION_PATH="${GIT_EXEC_PATH%/libexec/git-core}"
	COMPLETION_PATH="${COMPLETION_PATH%/lib/git-core}"
	COMPLETION_PATH="$COMPLETION_PATH/share/git/completion"
	if test -f "$COMPLETION_PATH/git-prompt.sh"
	then
		. "$COMPLETION_PATH/git-completion.bash"
		. "$COMPLETION_PATH/git-prompt.sh"
		# PS1="$PS1"'\[\033[36m\]'  # change color to cyan
		# PS1="$PS1"'`__git_ps1`'   # bash function
	fi
fi
# PS1="$PS1"'\n'                 # new line
PS1="$PS1"'\[\033[32m\]'       # change to green
PS1="$PS1"'$ '                 # prompt: always $
PS1="$PS1"'\[\033[0m\]'        # change color
# _set_bash_prompt

# ----------------------------------------------------------------

This version comments out the actual call (line 140), and so does nothing.

The edit I made to the proposed script was line 37 here, commenting out PS1, since that should already exist and have been built.