[FIX] Kamal: now works with images which need a gem user install

Author: RouL

.gitignore

@@ -47,3 +47,4 @@ tags
 [._]*.un~
 
 /output
+/temp

src/kamal/install.sh

@@ -28,7 +28,11 @@ gem_install() {
 
     case $RUBY_ENV in
         ruby)
-            su $USERNAME -c "gem install $PARAMS"
+            if [ "$GEM_HOME" != "" ] && ([ -d $GEM_HOME ] && [ -w $GEM_HOME ] || [ -d `dirname $GEM_HOME` ] && [ -w `dirname $GEM_HOME` ]); then
+                su $USERNAME -c "gem install $PARAMS"
+            else
+                su $USERNAME -c "gem install --user-install $PARAMS"
+            fi
             ;;
         mise)
             su $USERNAME -c "mise exec -- gem install $PARAMS"

test/kamal/test.sh

@@ -1,6 +1,8 @@
 #!/bin/bash
 set -e
 
+export PATH="$(ruby -r rubygems -e 'puts Gem.user_dir')/bin:$PATH"
+
 sudo apt-get update -y > /dev/null
 sudo apt-get install -y curl jq ca-certificates > /dev/null