[O] Install and update script (#4)

fastinstall.sh

@@ -7,8 +7,8 @@ if [ -d "zshrc" ]; then
   exit -1
 fi
 
-# Clone repo
-git clone "https://github.com/hykilpikonna/zshrc"
+# Clone repo without downloading old history.
+git clone --depth 1 --recurse-submodules --shallow-submodules "https://github.com/hykilpikonna/zshrc"
 
 # Addline function: add a line to a file if the line doesn't already exist
 addline() {
@@ -19,12 +19,6 @@ addline() {
 addline .zshrc 'SCR="$HOME/zshrc/scripts"'
 addline .zshrc '. $SCR/zshrc.sh'
 
-# Initialize submodules
-pushd zshrc
-git submodule init
-git submodule update
-popd
-
 # Return to the previous directory
 popd
 

scripts/includes/init/update.sh

@@ -1,22 +1,63 @@
-cd $SCR
+cd "$SCR" || return
 
 prefix="&7[&3zshrc&7]"
+remote_ref="${ZSHRC_UPDATE_REF:-origin/master}"
+
+_zshrc_stash_created=0
+_zshrc_stash_if_needed() {
+    if ! git diff --quiet --ignore-submodules -- \
+        || ! git diff --cached --quiet --ignore-submodules -- \
+        || [[ -n "$(git ls-files --others --exclude-standard)" ]]; then
+        if git stash push -u -m "zshrc auto-update before applying $remote_ref" >/dev/null; then
+            _zshrc_stash_created=1
+        fi
+    fi
+}
+
+_zshrc_restore_stash() {
+    if [[ "$_zshrc_stash_created" == "1" ]]; then
+        git stash pop >/dev/null || color "$prefix &cUpdated, but saved local changes need manual conflict resolution."
+    fi
+}
 
 # Check for updates
-git fetch origin --quiet
-reslog=$(git log HEAD..origin/master --oneline)
-if [[ "${reslog}" != "" ]] ; then
+if git fetch origin --quiet && git rev-parse --verify --quiet "$remote_ref" >/dev/null; then
+
+    # Handle rewritten or force-pushed history. This keeps auto-update working
+    # after repository cleanup that removes old large objects.
+    if ! git merge-base --is-ancestor HEAD "$remote_ref" 2>/dev/null; then
+        color "$prefix &cRepo history changed. Resetting local zshrc to $remote_ref..."
+
+        _zshrc_stash_if_needed
+        if git reset --hard "$remote_ref" && git submodule update --init --recursive --depth 1; then
+            _zshrc_restore_stash
+            . "$SCR/zshrc.sh"
+            color "$prefix &aUpdated after history rewrite!"
+        else
+            color "$prefix &cUpdate failed!"
+        fi
+    else
+        reslog=$(git log HEAD.."$remote_ref" --oneline)
+        if [[ "${reslog}" != "" ]] ; then
 
             # Has updates
             color "$prefix &cYour zshrc is outdated. Automatically updating..."
 
-    # Try to pull
-    if git stash & git pull & git stash pop; then
-        . $SCR/zshrc.sh
+            # Try to fast-forward without invoking git pull's merge/rebase behavior.
+            _zshrc_stash_if_needed
+            if git merge --ff-only "$remote_ref" && git submodule update --init --recursive --depth 1; then
+                _zshrc_restore_stash
+                . "$SCR/zshrc.sh"
                 color "$prefix &aUpdated!"
             else
                 color "$prefix &cUpdate failed!"
             fi
+        fi
+    fi
+elif [[ -n "$ZSHRC_UPDATE_VERBOSE" ]]; then
+    color "$prefix &cUpdate check failed!"
 fi
 
+unset -f _zshrc_stash_if_needed _zshrc_restore_stash
+unset _zshrc_stash_created remote_ref reslog
 cd - &> /dev/null