From c4fdc8f70804fea6f543e6bbf3964301e2537e36 Mon Sep 17 00:00:00 2001
From: Ben Hilburn <bhilburn@gmail.com>
Date: Thu, 11 Aug 2016 15:40:05 -0400
Subject: [PATCH] Improved speed of `prompt_vcs` by 50%-66%.

---
 functions/utilities.zsh | 16 +++++++++++++++-
 powerlevel9k.zsh-theme  | 23 +++++++++++++++--------
 2 files changed, 30 insertions(+), 9 deletions(-)

diff --git a/functions/utilities.zsh b/functions/utilities.zsh
index eed6ccc5..c9bd2e46 100644
--- a/functions/utilities.zsh
+++ b/functions/utilities.zsh
@@ -122,6 +122,20 @@ if [[ "$OS" == 'OSX' ]]; then
   fi
 fi
 
+# Determine if the passed segment is used in the prompt
+#
+# Pass the name of the segment to this function to test for its presence in
+# either the LEFT or RIGHT prompt arrays.
+#    * $1: The segment to be tested.
+segment_in_use() {
+    local key=$1
+    if [[ -n "${POWERLEVEL9K_LEFT_PROMPT_ELEMENTS[(r)$key]}" ]] || [[ -n "${POWERLEVEL9K_RIGHT_PROMPT_ELEMENTS[(r)$key]}" ]]; then
+        return 0
+    else
+        return 1
+    fi
+}
+
 # Print a deprecation warning if an old segment is in use.
 # Takes the name of an associative array that contains the
 # deprecated segments as keys, the values contain the new
@@ -131,7 +145,7 @@ print_deprecation_warning() {
   raw_deprecated_segments=(${(kvP@)1})
 
   for key in ${(@k)raw_deprecated_segments}; do
-    if [[ -n "${POWERLEVEL9K_LEFT_PROMPT_ELEMENTS[(r)$key]}" ]] || [[ -n "${POWERLEVEL9K_RIGHT_PROMPT_ELEMENTS[(r)$key]}" ]]; then
+    if segment_in_use $key; then
       # segment is deprecated
       print -P "%F{yellow}Warning!%f The '$key' segment is deprecated. Use '%F{blue}${raw_deprecated_segments[$key]}%f' instead. For more informations, have a look at the CHANGELOG.md."
     fi
diff --git a/powerlevel9k.zsh-theme b/powerlevel9k.zsh-theme
index 19886435..0860cff4 100755
--- a/powerlevel9k.zsh-theme
+++ b/powerlevel9k.zsh-theme
@@ -837,7 +837,7 @@ prompt_todo() {
 set_default POWERLEVEL9K_VCS_ACTIONFORMAT_FOREGROUND "red"
 # Default: Just display the first 8 characters of our changeset-ID.
 set_default POWERLEVEL9K_VCS_INTERNAL_HASH_LENGTH "8"
-prompt_vcs() {
+powerlevel9k_vcs_init() {
   if [[ -n "$POWERLEVEL9K_CHANGESET_HASH_LENGTH" ]]; then
     POWERLEVEL9K_VCS_INTERNAL_HASH_LENGTH="$POWERLEVEL9K_CHANGESET_HASH_LENGTH"
   fi
@@ -849,8 +849,7 @@ prompt_vcs() {
   VCS_WORKDIR_HALF_DIRTY=false
 
   # The vcs segment can have three different states - defaults to 'clean'.
-  local current_state=""
-  typeset -AH vcs_states
+  typeset -gAH vcs_states
   vcs_states=(
     'clean'         'green'
     'modified'      'yellow'
@@ -890,6 +889,12 @@ prompt_vcs() {
   if [[ "$POWERLEVEL9K_SHOW_CHANGESET" == true ]]; then
     zstyle ':vcs_info:*' get-revision true
   fi
+}
+
+prompt_vcs() {
+  VCS_WORKDIR_DIRTY=false
+  VCS_WORKDIR_HALF_DIRTY=false
+  current_state=""
 
   # Actually invoke vcs_info manually to gather all information.
   vcs_info
@@ -954,11 +959,8 @@ prompt_pyenv() {
 ################################################################
 # Prompt processing and drawing
 ################################################################
-
 # Main prompt
 build_left_prompt() {
-  defined POWERLEVEL9K_LEFT_PROMPT_ELEMENTS || POWERLEVEL9K_LEFT_PROMPT_ELEMENTS=(context dir rbenv vcs)
-
   local index=1
   for element in "${POWERLEVEL9K_LEFT_PROMPT_ELEMENTS[@]}"; do
     # Remove joined information in direct calls
@@ -980,8 +982,6 @@ build_left_prompt() {
 
 # Right prompt
 build_right_prompt() {
-  defined POWERLEVEL9K_RIGHT_PROMPT_ELEMENTS || POWERLEVEL9K_RIGHT_PROMPT_ELEMENTS=(status root_indicator background_jobs history time)
-
   local index=1
   for element in "${POWERLEVEL9K_RIGHT_PROMPT_ELEMENTS[@]}"; do
     # Remove joined information in direct calls
@@ -1050,6 +1050,9 @@ powerlevel9k_init() {
       print -P "\t%F{red}WARNING!%f %F{blue}export LANG=\"en_US.UTF-8\"%f at the top of your \~\/.zshrc is sufficient."
   fi
 
+  defined POWERLEVEL9K_LEFT_PROMPT_ELEMENTS || POWERLEVEL9K_LEFT_PROMPT_ELEMENTS=(context dir rbenv vcs)
+  defined POWERLEVEL9K_RIGHT_PROMPT_ELEMENTS || POWERLEVEL9K_RIGHT_PROMPT_ELEMENTS=(status root_indicator background_jobs history time)
+
   # Display a warning if deprecated segments are in use.
   typeset -AH deprecated_segments
   # old => new
@@ -1067,6 +1070,10 @@ powerlevel9k_init() {
   # initialize colors
   autoload -U colors && colors
 
+  if segment_in_use "vcs"; then
+    powerlevel9k_vcs_init
+  fi
+
   # initialize hooks
   autoload -Uz add-zsh-hook