From d9cdc20ce61d561cafd39435e16ce7f394fb987b Mon Sep 17 00:00:00 2001
From: Andrew Janke <andrew@apjanke.net>
Date: Wed, 23 Sep 2015 18:41:48 -0400
Subject: [PATCH] installer: use timestamped backups to preserve all old zshrcs

---
 tools/install.sh   | 24 ++++++++++++++++++++++++
 tools/uninstall.sh | 21 ++++++++++-----------
 2 files changed, 34 insertions(+), 11 deletions(-)

diff --git a/tools/install.sh b/tools/install.sh
index 8cba52085..d6bd07afc 100755
--- a/tools/install.sh
+++ b/tools/install.sh
@@ -58,6 +58,30 @@ main() {
     exit 1
   }
 
+  # Keep most recent old .zshrc at .zshrc.pre-oh-my-zsh, and older ones
+  # with datestamp of installation that moved them aside, so we never actually
+  # destroy a user's original zshrc
+  printf "${BLUE}Looking for an existing zsh config...${NORMAL}\n"
+  # Must use this exact name so uninstall.sh can find it
+  OLD_ZSHRC=~/.zshrc.pre-oh-my-zsh
+  if [ -f ~/.zshrc ] || [ -h ~/.zshrc ]; then
+    if [ -e "$OLD_ZSHRC" ]; then
+      TIMESTAMP="$(date +%Y-%m-%d_%H-%M-%S)"
+      OLD_OLD_ZSHRC="${OLD_ZSHRC}-${TIMESTAMP}"
+      if [ -e "$OLD_OLD_ZSHRC" ]; then
+        echo "Error: $OLD_OLD_ZSHRC exists" >&2
+        echo "Just re-run this again in a couple seconds" &>2
+        exit 1
+      fi
+      mv "$OLD_ZSHRC" "${OLD_OLD_ZSHRC}"
+      # intentional omitted newline
+      printf "${YELLOW}Found old ~/.zshrc.pre-oh-my-zsh.${NORMAL} "
+      printf "${GREEN}Backing up to ${OLD_OLD_ZSHRC}${NORMAL}\n"
+    fi
+    printf "${YELLOW}Found ~/.zshrc.${NORMAL} ${GREEN}Backing up to ${OLD_ZSHRC}${NORMAL}\n"
+    mv ~/.zshrc "$OLD_ZSHRC";
+  fi
+
   # The Windows (MSYS) Git is not compatible with normal use on cygwin
   if [ "$OSTYPE" = cygwin ]; then
     if git --version | grep msysgit > /dev/null; then
diff --git a/tools/uninstall.sh b/tools/uninstall.sh
index 9ad1b64a6..add6d7e30 100644
--- a/tools/uninstall.sh
+++ b/tools/uninstall.sh
@@ -6,24 +6,23 @@ then
 fi
 
 echo "Removing ~/.oh-my-zsh"
-if [ -d ~/.oh-my-zsh ]
-then
+if [ -d ~/.oh-my-zsh ]; then
   rm -rf ~/.oh-my-zsh
 fi
 
 echo "Looking for original zsh config..."
-if [ -f ~/.zshrc.pre-oh-my-zsh ] || [ -h ~/.zshrc.pre-oh-my-zsh ]
-then
-  echo "Found ~/.zshrc.pre-oh-my-zsh -- Restoring to ~/.zshrc";
+ZSHRC_ORIG=~/.zshrc.pre-oh-my-zsh
+if [ -e "$ZSHRC_ORIG" ]; then
+  echo "Found $ZSHRC_ORIG -- Restoring to ~/.zshrc";
 
-  if [ -f ~/.zshrc ] || [ -h ~/.zshrc ]
-  then
-    ZSHRC_SAVE=".zshrc.omz-uninstalled-`date +%Y%m%d%H%M%S`";
-    echo "Found ~/.zshrc -- Renaming to ~/${ZSHRC_SAVE}";
-    mv ~/.zshrc ~/${ZSHRC_SAVE};
+  if [ -e ~/.zshrc ]; then
+    TIMESTAMP=$(date +%Y-%m-%d_%H-%M-%S)
+    ZSHRC_SAVE=~/.zshrc.omz-uninstalled-$TIMESTAMP;
+    echo "Found ~/.zshrc -- Renaming to ${ZSHRC_SAVE}";
+    mv ~/.zshrc ${ZSHRC_SAVE};
   fi
 
-  mv ~/.zshrc.pre-oh-my-zsh ~/.zshrc;
+  mv "$ZSHRC_ORIG" ~/.zshrc;
 
   source ~/.zshrc;
 else