home-environment: colorize activation output slightly

modules/lib-bash/activation-init.sh

@@ -0,0 +1,61 @@
+function setupVars() {
+    local profilesPath="/nix/var/nix/profiles/per-user/$USER"
+    local gcPath="/nix/var/nix/gcroots/per-user/$USER"
+    local greatestGenNum
+
+    greatestGenNum=$( \
+        find "$profilesPath" -name 'home-manager-*-link' \
+            | sed 's/^.*-\([0-9]*\)-link$/\1/' \
+            | sort -rn \
+            | head -1)
+
+    if [[ -n "$greatestGenNum" ]] ; then
+        oldGenNum=$greatestGenNum
+        newGenNum=$((oldGenNum + 1))
+    else
+        newGenNum=1
+    fi
+
+    if [[ -e "$gcPath/current-home" ]] ; then
+        oldGenPath="$(readlink -e "$gcPath/current-home")"
+    fi
+
+    genProfilePath="$profilesPath/home-manager"
+    newGenPath="@GENERATION_DIR@";
+    newGenProfilePath="$profilesPath/home-manager-$newGenNum-link"
+    newGenGcPath="$gcPath/current-home"
+}
+
+setupVars
+
+echo "Starting home manager activation"
+
+if [[ -v VERBOSE ]]; then
+    export VERBOSE_ECHO=echo
+    export VERBOSE_ARG="--verbose"
+else
+    export VERBOSE_ECHO=true
+    export VERBOSE_ARG=""
+fi
+
+if [[ -v DRY_RUN ]] ; then
+    $VERBOSE_ECHO "This is a dry run"
+    export DRY_RUN_CMD=echo
+else
+    $VERBOSE_ECHO "This is a live run"
+    export DRY_RUN_CMD=""
+fi
+
+$VERBOSE_ECHO "Activation variables:"
+if [[ -v oldGenNum ]] ; then
+    $VERBOSE_ECHO "  oldGenNum=$oldGenNum"
+    $VERBOSE_ECHO "  oldGenPath=$oldGenPath"
+else
+    $VERBOSE_ECHO "  oldGenNum undefined (first run?)"
+    $VERBOSE_ECHO "  oldGenPath undefined (first run?)"
+fi
+$VERBOSE_ECHO "  newGenPath=$newGenPath"
+$VERBOSE_ECHO "  newGenNum=$newGenNum"
+$VERBOSE_ECHO "  newGenProfilePath=$newGenProfilePath"
+$VERBOSE_ECHO "  newGenGcPath=$newGenGcPath"
+$VERBOSE_ECHO "  genProfilePath=$genProfilePath"