Re: [RFC][PATCH] `newuser` prompt theme

[Marlon Richert <marlon.richert@xxxxxxxxx>]

> On 16 Apr 2021, at 20:13, Daniel Shahaf <d.s@xxxxxxxxxxxxxxxxxx> wrote:
> 
> Marlon wrote on Fri, Apr 16, 2021 at 19:04:06 +0300:
>> Question for Daniel: If you’re going to add sysexits(3) to PRINT_EXIT_VALUE anyway (workers/48564), should I just get rid of prompt_vcs_precmd()? Or do you think it still adds value?
> 
> IMO keep that function.  We can always simplify that function if and when
> sysexits(3) PRINT_EXIT_VALUE support is added.
> 
> You seem to have sent the patch three times, nested.  Which one should
> be reviewed?

Whoops! Here’s the patch again, but this time just once.

From f11694bc0260de5d4572fdacb0f41fc748bd7155 Mon Sep 17 00:00:00 2001
From: Marlon Richert <marlon.richert@xxxxxxxxx>
Date: Thu, 15 Apr 2021 23:28:56 +0300
Subject: [PATCH] Add customizable `vcs` prompt theme

---
 Functions/Prompts/prompt_vcs_setup | 227 +++++++++++++++++++++++++++++
 1 file changed, 227 insertions(+)
 create mode 100644 Functions/Prompts/prompt_vcs_setup

diff --git a/Functions/Prompts/prompt_vcs_setup b/Functions/Prompts/prompt_vcs_setup
new file mode 100644
index 000000000..66f167f49
--- /dev/null
+++ b/Functions/Prompts/prompt_vcs_setup
@@ -0,0 +1,227 @@
+##
+# Prompt that can be customized through vcs_info
+#
+
+autoload -Uz add-zle-hook-widget add-zsh-hook vcs_info
+
+# Standardized exit codes. See `man 3 sysexits`.
+if [[ ${(t)sysexits} != *readonly* ]]; then
+  # Avoid error in case this has been set already.
+  readonly -ga sysexits=(
+      USAGE
+      DATAERR
+      NOINPUT
+      NOUSER
+      NOHOST
+      UNAVAILABLE
+      SOFTWARE
+      OSERR
+      OSFILE
+      CANTCREAT
+      IOERR
+      TEMPFAIL
+      PROTOCOL
+      NOPERM
+      CONFIG
+  )
+fi
+
+# Prompt segments
+readonly -gHA _prompt_vcs_defaults=(
+    start:chpwd     $'\n%B%F{blue}%~%%b%f/\n'
+    start:left      $'%%(?,%F{green},%F{red}%v%k\n%B%%S)%#%%b%f%%s '
+    start:right     '%B%F{blue}%n%b%f%k@%F{magenta}%m%f'
+    start:staged    '%B%F{green}+%b%f'
+    start:unstaged  '%B%F{red}*%b%f'
+    start:action    '%B%F{red}%a%%b%f'
+    start:branch    '%B%F{cyan}%b%%b%f'
+    start:repo      '|%B%F{blue}%r%%b%f'
+    cont:indent     '  '
+    cont:left       ''
+    cont:right      '%F{red}%^%f'
+)
+
+prompt_vcs_help() {
+  print -r -- \
+"This prompt theme can by customized by copy-pasting any of the code below to
+your .zshrc file and editing it there:'
+
+  # For each of these,
+  # * the first string is used for \$PS1 after changing dirs,
+  # * the second string is used for \$PS1 otherwise, and
+  # * the third string is used for \$RPS1 and updated asynchronously.
+  # In these, %v expands to the name (if any) & number of the last exit code.
+  zstyle ':vcs_info:*:prompt_vcs:*' nvcsformats \
+      "${${:-$_prompt_vcs_defaults[start:chpwd]$_prompt_vcs_defaults[start:left]}//'%%'/%}" \
+      "${_prompt_vcs_defaults[start:left]//'%%'/%}" \
+      "${_prompt_vcs_defaults[start:right]//'%%'/%}"
+  zstyle ':vcs_info:*:prompt_vcs:*' formats \\
+      ${(q+):-$_prompt_vcs_defaults[start:chpwd]$_prompt_vcs_defaults[start:left]} \\
+      ${(q+)_prompt_vcs_defaults[start:left]} \\
+      ${(q+):-%u%c$_prompt_vcs_defaults[start:branch]$_prompt_vcs_defaults[start:repo]}
+  zstyle ':vcs_info:*:prompt_vcs:*' actionformats \\
+      ${(q+):-$_prompt_vcs_defaults[start:chpwd]$_prompt_vcs_defaults[start:left]} \\
+      ${(q+)_prompt_vcs_defaults[start:left]} \\
+      ${(q+):-%u%c$_prompt_vcs_defaults[start:action]$_prompt_vcs_defaults[start:repo]}
+
+  # These set the values of %c and %u, respectively:
+  zstyle ':vcs_info:*:prompt_vcs:*' stagedstr ${(q+)_prompt_vcs_defaults[start:staged]}
+  zstyle ':vcs_info:*:prompt_vcs:*' unstagedstr ${(q+)_prompt_vcs_defaults[start:unstaged]}
+
+For more info on the config above, see
+http://zsh.sourceforge.net/Doc/Release/Prompt-Expansion.html and the end of
+http://zsh.sourceforge.net/Doc/Release/User-Contributions.html#vcs_005finfo-Configuration";
+}
+
+# Sets a style if it hasn't been set yet.
+_prompt_vcs_zstyle() {
+  local -a val
+  zstyle -g val "$1" "$2"
+  (( $#val )) ||
+      zstyle "$@"
+}
+
+_prompt_vcs_info() {
+  _prompt_vcs_zstyle ':vcs_info:*:prompt_vcs:*' max-exports 3 # Default is 2.
+
+  _prompt_vcs_zstyle ':vcs_info:*:prompt_vcs:*' nvcsformats \
+      "${${:-$_prompt_vcs_defaults[start:chpwd]$_prompt_vcs_defaults[start:left]}//'%%'/%}" \
+      "${_prompt_vcs_defaults[start:left]//'%%'/%}" \
+      "${_prompt_vcs_defaults[start:right]//'%%'/%}"
+  _prompt_vcs_zstyle ':vcs_info:*:prompt_vcs:*' formats \
+      "$_prompt_vcs_defaults[start:chpwd]$_prompt_vcs_defaults[start:left]" \
+      "$_prompt_vcs_defaults[start:left]" \
+      "%u%c$_prompt_vcs_defaults[start:branch]$_prompt_vcs_defaults[start:repo]"
+  _prompt_vcs_zstyle ':vcs_info:*:prompt_vcs:*' actionformats \
+      "$_prompt_vcs_defaults[start:chpwd]$_prompt_vcs_defaults[start:left]" \
+      "$_prompt_vcs_defaults[start:left]" \
+      "%u%c$_prompt_vcs_defaults[start:action]$_prompt_vcs_defaults[start:repo]"
+  _prompt_vcs_zstyle ':vcs_info:*:prompt_vcs:*' stagedstr \
+      "$_prompt_vcs_defaults[start:staged]"
+  _prompt_vcs_zstyle ':vcs_info:*:prompt_vcs:*' unstagedstr \
+      "$_prompt_vcs_defaults[start:unstaged]"
+
+  vcs_info prompt_vcs # Call with namespace.
+
+  print -rNC1 -- \
+      "${(q+)vcs_info_msg_0_}" "${(q+)vcs_info_msg_1_}" "${(q+)vcs_info_msg_2_}"
+}
+
+prompt_vcs_chpwd() {
+  emulate -L zsh
+
+  local -i fd=-1; local -a reply
+  exec {fd}< <(
+    # Fetch only staged changes at this point, for performance reasons.
+    _prompt_vcs_zstyle ':vcs_info:*:prompt_vcs:*' check-for-staged-changes yes
+    _prompt_vcs_info
+  )
+  IFS=$'\0' read -Aru "$fd"
+  typeset -ga _prompt_vcs_info_msg_=( "${(@Q)reply}" )
+  exec {fd}<&-
+
+  PS1="$_prompt_vcs_info_msg_[1]"
+  RPS1="$_prompt_vcs_info_msg_[3]"
+}
+
+prompt_vcs_precmd() {
+  local exitstatus=$? # Exit status of last command
+  emulate -L zsh
+
+  # Assign human-friendly exit status string to %v.
+  psvar[1]=
+  case $exitstatus in
+    ( <128-> )
+      psvar[1]="SIG$signals[exitstatus-127] "
+      ;|
+    ( <64-78> )
+      psvar[1]="EX_$sysexits[exitstatus-63] "
+      ;|
+    ( <1-> )
+      psvar[1]+="($exitstatus)"
+      ;;
+    # No need to show EX_OK.
+  esac
+}
+
+prompt_vcs_line-init() {
+  emulate -L zsh
+
+  case $CONTEXT in
+    start ) # (R)PS1
+      # Asynchronously check for unstaged changes. Do this here & not in
+      # precmd, so you can press Enter on an empty line to update VCS info.
+      local -i fd=-1
+      exec {fd}< <(
+        _prompt_vcs_zstyle ':vcs_info:*:prompt_vcs:*' check-for-changes yes
+        _prompt_vcs_info
+        print -r -- "$PWD"
+      )
+
+      # Add callback. Needs to be a widget, so we can refresh the prompt.
+      zle -Fw "$fd" prompt_vcs_fd-handler
+      ;;
+    cont )  # (R)PS2
+      # Indent left continuation prompt for each open shell construct.
+      local fmt="$_prompt_vcs_defaults[cont:indent]"
+      local -a indent=( '%('{1..$(( COLUMNS / ${(m)#fmt} ))}"_,$fmt,)" )
+      PS2="${(j::)indent}$_prompt_vcs_defaults[cont:left]"
+
+      RPS2="$_prompt_vcs_defaults[cont:right]"
+      ;;
+  esac
+}
+
+# Callback widget function for our async fetch of unstaged VCS changes
+prompt_vcs_fd-handler() {
+  emulate -L zsh
+
+  local -i fd=$1; local sig=$2; local -a reply
+  {
+    zle -F "$fd"  # Detach ourselves, so we don't get called more than once.
+
+    [[ $sig != (|hup) ]] &&
+        return  # Error occured
+
+    IFS=$'\0' read -Aru "$fd"
+
+    [[ $reply[-1] != $PWD ]] &&
+        return  # Abort if the info is not for the current dir.
+  } always {
+    exec {fd}<&-
+  }
+  shift -p reply
+  typeset -ga _prompt_vcs_info_msg_=( "${(@Q)reply}" )
+  RPS1="$_prompt_vcs_info_msg_[3]"
+  zle .reset-prompt
+}
+
+prompt_vcs_line-finish() {
+  emulate -L zsh
+  PS1="$_prompt_vcs_info_msg_[2]"
+}
+
+prompt_vcs_setup() {
+  prompt_opts=( cr percent sp ) # Tell promptinit which options to set.
+
+  PS4=$'# ?=%(?,%F{green},%B%F{red}%S)%?%b%f%s e=%e %F{green}%1N%f:%I %(1_,%F{yellow}%K{black}%_%f%k ,)'
+  SPROMPT='Correct %B%F{red}%U%R%b%f%u to %B%F{green}%r%b%f? [%Sy%ses|%Sn%so|%Se%sdit|%Sa%sbort] '
+  PROMPT_EOL_MARK='%S%F{cyan}%#%s%f'
+  zle_highlight=(
+      isearch:fg=black,bg=yellow
+      special:fg=cyan,bold
+      region:bg=blue
+      suffix:bg=blue
+      paste:none
+  )
+
+  add-zsh-hook chpwd    prompt_vcs_chpwd
+  add-zsh-hook precmd   prompt_vcs_precmd
+  add-zle-hook-widget line-init   prompt_vcs_line-init
+  add-zle-hook-widget line-finish prompt_vcs_line-finish
+  zle -N prompt_vcs_fd-handler # Callback widget for async VCS update.
+
+  prompt_vcs_chpwd
+}
+
+prompt_vcs_setup "$@"
-- 
2.31.1