From c5e63fec2cda9dce6f867a51af1991b175f66baa Mon Sep 17 00:00:00 2001
From: Michael Lamparski <diagonaldevice@gmail.com>
Date: Sat, 24 Jul 2021 20:52:02 -0400
Subject: [PATCH] refactor prompt, work around pyenv perf nightmares

---
 shell/bashrc.include        | 47 ++++++++++++++++++++++---------------
 shell/bashrc.prompt.d/git   |  3 +--
 shell/bashrc.prompt.d/pyenv | 13 +++++-----
 shell/colors.include        | 12 ----------
 shell/colors.ps1.include    | 22 +++++++++++++++++
 shell/common.include        | 15 ++++++++++++
 6 files changed, 73 insertions(+), 39 deletions(-)
 delete mode 100644 shell/colors.include
 create mode 100644 shell/colors.ps1.include

diff --git a/shell/bashrc.include b/shell/bashrc.include
index 188ef2d..eb3267c 100644
--- a/shell/bashrc.include
+++ b/shell/bashrc.include
@@ -2,10 +2,18 @@
 
 # To be source'd in .bashrc
 
+# running 'which' can actually get pretty expensive (especially on wsl2) so we cache these
+which git 1>/dev/null 2>/dev/null && __EXPHP_BASH_PROMPT__HAS_GIT=1
+
+# FIXME: this currently always fails due to initialization order (common.include runs after this)
+which pyenv 1>/dev/null 2>/dev/null && __EXPHP_BASH_PROMPT__HAS_PYENV=1
+
 # Wrap in a function so that `local` can be used.
 # Awkwardly long name to avoid collision.
-doTheSpecialPromptyThing() {(  # scope the colors
-  . $HOME/dotfiles/shell/colors.include
+__exphpBashrcPromptCommand() {
+  local __PREV_EXIT_CODE="$?" # This needs to be first
+
+  . $HOME/dotfiles/shell/colors.ps1.include --local
 
   local lbrace="$white["
   local rbrace="$white]"
@@ -25,10 +33,15 @@ doTheSpecialPromptyThing() {(  # scope the colors
     dd-win10\
   ; do [[ $HOSTNAME == $tmp ]] && my_machine=1; done
 
-  # == STATIC REGION ==
-  # no command substitutions may be used before the error indicator,
-  # to ensure that the value of $? is preserved.
+  # == RESET ==
   PS1=""
+
+  # == PYENV ==
+  if [[ $__EXPHP_BASH_PROMPT__HAS_PYENV ]]; then
+    PS1+="$($HOME/dotfiles/shell/bashrc.prompt.d/pyenv)"
+  fi
+
+  # == MAIN STUFF ==
   PS1+="$lbrace "
   if [[ $my_machine ]]; then
     # Username & Time
@@ -46,15 +59,15 @@ doTheSpecialPromptyThing() {(  # scope the colors
   PS1+=" $rbrace "
 
   # == ERROR INDICATOR ==
-  PS1+="\$(if [[ \$? != 0 ]];"
-  PS1+="then echo \"($red!!!$white) \"; "
-  PS1+="fi)"
+  if [[ $__PREV_EXIT_CODE -ne 0  ]]; then
+    PS1+="($red!!!$white) "
+  fi
 
   # == DYNAMIC REGION ==
-  PS1+="\$(
-    \$HOME/dotfiles/shell/bashrc.prompt.d/pyenv
-    \$HOME/dotfiles/shell/bashrc.prompt.d/git
-  )"
+  # Git branch
+  if [[ $__EXPHP_BASH_PROMPT__HAS_GIT ]]; then
+    PS1+="$($HOME/dotfiles/shell/bashrc.prompt.d/git)"
+  fi
 
   # Current directory
   PS1+="$green\w$none"
@@ -62,13 +75,9 @@ doTheSpecialPromptyThing() {(  # scope the colors
   # Prompt on newline
   PS1+="\n"
   PS1+="${white}\\\$${none} "
-  echo "$PS1"  # let it escape the subshell
-)}
-
-PS1=$(doTheSpecialPromptyThing)
+}
 
-# cleanup
-unset -f doTheSpecialPromptyThing
+PROMPT_COMMAND=__exphpBashrcPromptCommand
 
 __bashrc__is_bash_ge() {
     local maj
@@ -105,5 +114,5 @@ else
 
     # Add to the history after each command finishes
     NEWLINE=$'\n'
-    PROMPT_COMMAND="history -a $NEWLINE $PROMPT_COMMAND"
+    PROMPT_COMMAND="$PROMPT_COMMAND $NEWLINE history -a"
 fi
diff --git a/shell/bashrc.prompt.d/git b/shell/bashrc.prompt.d/git
index 205055d..7288b99 100755
--- a/shell/bashrc.prompt.d/git
+++ b/shell/bashrc.prompt.d/git
@@ -1,7 +1,6 @@
 #!/usr/bin/env bash
-which git 1>/dev/null 2>/dev/null || exit 0
 
-. $HOME/dotfiles/shell/colors.include
+. $HOME/dotfiles/shell/colors.ps1.include
 . $HOME/dotfiles/shell/gittool.ps1.include  # compute git status into GITTOOL variables
 if [[ $EXPHP_GITTOOL_BRANCH ]]; then
   echo -n "$none("
diff --git a/shell/bashrc.prompt.d/pyenv b/shell/bashrc.prompt.d/pyenv
index ffdbc26..4b3c70e 100755
--- a/shell/bashrc.prompt.d/pyenv
+++ b/shell/bashrc.prompt.d/pyenv
@@ -1,10 +1,11 @@
 #!/usr/bin/env bash
 
-which pyenv 1>/dev/null 2>/dev/null || exit 0
+. $HOME/dotfiles/shell/colors.ps1.include
 
-. $HOME/dotfiles/shell/colors.include
-
-version=$(pyenv version-name)
-if [[ "$version" != 'system' ]]; then
-    echo -n "(${cyan}$version${none}${bold}) ${none}"
+# DO NOT USE 'pyenv version-name'
+# IT IS SO SLOW
+# YOU WILL MAKE YOUR PROMPT SO SLOW
+version=$PYENV_VERSION
+if [[ $version && "$version" != 'system' ]]; then
+    echo -n "(${cyan}$version${none}) ${none}"
 fi
diff --git a/shell/colors.include b/shell/colors.include
deleted file mode 100644
index a8df076..0000000
--- a/shell/colors.include
+++ /dev/null
@@ -1,12 +0,0 @@
-# these will be global so you should probably be in a subshell or a non-sourced script when
-# you source this
-
-none=$'\033[00m'
-bold=$'\033[01m'
-red=$'\033[01;31m'
-green=$'\033[01;32m'
-yellow=$'\033[01;33m'
-blue=$'\033[01;34m'
-purple=$'\033[01;35m'
-cyan=$'\033[01;36m'
-white=$'\033[01;37m'
diff --git a/shell/colors.ps1.include b/shell/colors.ps1.include
new file mode 100644
index 0000000..d282e52
--- /dev/null
+++ b/shell/colors.ps1.include
@@ -0,0 +1,22 @@
+if [[ $1 == "--local" ]]; then
+    # Note:  The \[ and \] are PS1 stuff to fix the positioning when using escape codes.
+    local none='\['$'\033[00m''\]'
+    local bold='\['$'\033[01m''\]'
+    local red='\['$'\033[01;31m''\]'
+    local green='\['$'\033[01;32m''\]'
+    local yellow='\['$'\033[01;33m''\]'
+    local blue='\['$'\033[01;34m''\]'
+    local purple='\['$'\033[01;35m''\]'
+    local cyan='\['$'\033[01;36m''\]'
+    local white='\['$'\033[01;37m''\]'
+else
+    none='\['$'\033[00m''\]'
+    bold='\['$'\033[01m''\]'
+    red='\['$'\033[01;31m''\]'
+    green='\['$'\033[01;32m''\]'
+    yellow='\['$'\033[01;33m''\]'
+    blue='\['$'\033[01;34m''\]'
+    purple='\['$'\033[01;35m''\]'
+    cyan='\['$'\033[01;36m''\]'
+    white='\['$'\033[01;37m''\]'
+fi
diff --git a/shell/common.include b/shell/common.include
index 93e5f6b..b8d22e6 100644
--- a/shell/common.include
+++ b/shell/common.include
@@ -173,8 +173,23 @@ if [ -e $HOME/asd/manage/pyenv ]; then
   # pyenv startup part 2:  The part that actually belongs in .bashrc
   eval "$(pyenv init -)"
   eval "$(pyenv virtualenv-init -)"
+
+  # _pyenv_virtualenv_hook makes the shell absurdly slow so get rid of it
+  # https://github.com/pyenv/pyenv-virtualenv/issues/259
+  #
+  # Warning: unloading the following hook breaks command
+  # `pyenv activate/deactivate`. Please switch to
+  # `pyenv shell env_name`, `pyenv shell --unset` instead.
+  if [[ -n $ZSH_VERSION ]]; then
+    autoload -Uz add-zsh-hook
+    add-zsh-hook -D precmd _pyenv_virtualenv_hook
+  fi
+  if [[ -n $BASH_VERSION ]]; then
+    PROMPT_COMMAND="${PROMPT_COMMAND/_pyenv_virtualenv_hook;/}"
+  fi
 fi
 
+
 # # Bumper rail.
 # # Limit memory for interactive bash prompts, because thrashing sucks.
 # # To bypass, invoke 'nolimit' from *outside* of a bash process.