install.sh: Add uninstall command

[why]
Maybe people would like to uninstall the fonts installed with the
script.

In fact the uninstall could already be acieved by giving the --clean
option and installing no new font. Well, apart from the fact that the
scripts prevents runs with no installed font. And then the user must
specify the same installpath that has been used for the install, which
is a bit tedious.

[how]
Add new command '--remove' (with no short option).
Make -L / --list option a dry-run option for --remove.
Uninstall both possible installpaths.

Fixes: #407

Signed-off-by: Fini Jastrow <ulf.fini.jastrow@desy.de>

install.sh

@@ -1,11 +1,12 @@
 #!/usr/bin/env bash
 # Install Nerd Fonts
-__ScriptVersion="0.3"
+__ScriptVersion="0.4"
 
 # Default values for option variables:
 quiet=false
 mode="copy"
 clean=false
+dry=false
 extension="otf"
 patches=("Complete") # There are no other variants then Complete anymore
 compat=()
@@ -14,7 +15,7 @@ installpath="user"
 # Usage info
 usage() {
   cat << EOF
-Usage: ./install.sh [-q -v -h] [[--copy | --link] --clean | --list]
+Usage: ./install.sh [-q -v -h] [[--copy | --link] --clean | --list | --remove]
                     [--use-single-width-glyphs] [--windows] [--otf | --ttf]
                     [--install-to-user-path | --install-to-system-path ]
                     [FONT...]
@@ -32,6 +33,10 @@ General options:
   -C, --clean                   Recreate the root Nerd Fonts target directory
                                 (clean out all previous copies or symlinks).
 
+  --remove                      Remove all Nerd Fonts (that have been installed
+                                with this script).
+                                Can be combined with -L for a dry run.
+
   -s, --use-single-width-glyphs Install single-width glyphs variants.
   -w, --windows                 Install with limited internal font names.
 
@@ -59,7 +64,8 @@ while getopts "$optspec" optchar; do
     h) usage; exit 0;;
     c) mode="copy";;
     l) mode="link";;
-    L) mode="list";;
+    L) dry=true
+       [ "$mode" != "remove" ] && mode="list";;
     C) clean=true;;
     s) compat=( "${compat[@]}" "Nerd Font*Mono" );;
     w) compat=( "${compat[@]}" "Windows Compatible" );;
@@ -76,7 +82,9 @@ while getopts "$optspec" optchar; do
         help) usage; exit 0;;
         copy) mode="copy";;
         link) mode="link";;
-        list) mode="list";;
+        list) dry=true
+              [ "$mode" != "remove" ] && mode="list";;
+        remove) mode="remove";;
         clean) clean=true;;
         use-single-width-glyphs) compat=( "${compat[@]}" "Nerd Font*Mono" );;
         windows) compat=( "${compat[@]}" "Windows Compatible" );;
@@ -206,20 +214,21 @@ done
 # Get target root directory
 if [[ $(uname) == 'Darwin' ]]; then
   # MacOS
-  if [[ "system" == "$installpath" ]]; then
-    font_dir="/Library/Fonts"
-  else
-    font_dir="$HOME/Library/Fonts"
-  fi
+  sys_font_dir="/Library/Fonts"
+  usr_font_dir="$HOME/Library/Fonts"
 else
   # Linux
-  if [[ "system" == "$installpath" ]]; then
-    font_dir="/usr/local/share/fonts"
-  else
-    font_dir="$HOME/.local/share/fonts"
-  fi
+  sys_font_dir="/usr/local/share/fonts"
+  usr_font_dir="$HOME/.local/share/fonts"
+fi
+sys_font_dir="${sys_font_dir}/NerdFonts"
+usr_font_dir="${usr_font_dir}/NerdFonts"
+
+if [[ "system" == "$installpath" ]]; then
+  font_dir="${sys_font_dir}"
+else
+  font_dir="${usr_font_dir}"
 fi
-font_dir="${font_dir}/NerdFonts"
 
 #
 # Take the desired action
@@ -252,12 +261,29 @@ case $mode in
         ;;
     esac;;
 
+  remove)
+    if [[ "true" == "$dry" ]]; then
+      echo "Dry run. Would issue these commands:"
+      [ "$quiet" = false ] && echo rm -rfv "$sys_font_dir" "$usr_font_dir"
+      [ "$quiet" = true ] && echo rm -rf "$sys_font_dir" "$usr_font_dir"
+    else
+      [ "$quiet" = false ] && rm -rfv "$sys_font_dir" "$usr_font_dir"
+      [ "$quiet" = true ] && rm -rf "$sys_font_dir" "$usr_font_dir"
+    fi
+    font_dir="$sys_font_dir $usr_font_dir"
+    ;;
+
 esac
 
 # Reset font cache on Linux
 if [[ -n $(command -v fc-cache) ]]; then
-  [ "$quiet" = false ] && fc-cache -vf "$font_dir"
-  [ "$quiet" = true ] && fc-cache -f "$font_dir"
+  if [[ "true" == "$dry" ]]; then
+    [ "$quiet" = false ] && echo fc-cache -vf "$font_dir"
+    [ "$quiet" = true ] && echo fc-cache -f "$font_dir"
+  else
+    [ "$quiet" = false ] && fc-cache -vf "$font_dir"
+    [ "$quiet" = true ] && fc-cache -f "$font_dir"
+  fi
   case $? in
     [0-1])
       # Catch fc-cache returning 1 on a success