compound tags from scarpet are saved compressed and allowing to read compressed compounds as well.

src/main/java/carpet/script/api/Auxiliary.java

@@ -88,12 +88,12 @@ public class Auxiliary {
     public static final String MARKER_STRING = "__scarpet_marker";
     private static final Map<String, SoundCategory> mixerMap = Arrays.stream(SoundCategory.values()).collect(Collectors.toMap(SoundCategory::getName, k -> k));
 
-    public static String recognizeResource(Value value)
+    public static String recognizeResource(Value value, boolean isFloder)
     {
         String origfile = value.getString();
         String file = origfile.toLowerCase(Locale.ROOT).replaceAll("[^A-Za-z0-9\\-+_/]", "");
         file = Arrays.stream(file.split("/+")).filter(s -> !s.isEmpty()).collect(Collectors.joining("/"));
-        if (file.isEmpty())
+        if (file.isEmpty() && !isFloder)
         {
             throw new InternalExpressionException("Cannot use "+origfile+" as resource name - must have some letters and numbers");
         }
@@ -786,7 +786,7 @@ public class Auxiliary {
         });
 
         expression.addLazyFunction("read_file", 2, (c, t, lv) -> {
-            String resource = recognizeResource(lv.get(0).evalValue(c));
+            String resource = recognizeResource(lv.get(0).evalValue(c), false);
             String origtype = lv.get(1).evalValue(c).getString().toLowerCase(Locale.ROOT);
             boolean shared = origtype.startsWith("shared_");
             String type = shared ? origtype.substring(7) : origtype; //len(shared_)
@@ -809,7 +809,7 @@ public class Auxiliary {
         });
 
         expression.addLazyFunction("delete_file", 2, (c, t, lv) -> {
-            String resource = recognizeResource(lv.get(0).evalValue(c));
+            String resource = recognizeResource(lv.get(0).evalValue(c), false);
             String origtype = lv.get(1).evalValue(c).getString().toLowerCase(Locale.ROOT);
             boolean shared = origtype.startsWith("shared_");
             String type = shared ? origtype.substring(7) : origtype; //len(shared_)
@@ -821,7 +821,7 @@ public class Auxiliary {
 
         expression.addLazyFunction("write_file", -1, (c, t, lv) -> {
             if (lv.size() < 3) throw new InternalExpressionException("'write_file' requires three or more arguments");
-            String resource = recognizeResource(lv.get(0).evalValue(c));
+            String resource = recognizeResource(lv.get(0).evalValue(c), false);
             String origtype = lv.get(1).evalValue(c).getString().toLowerCase(Locale.ROOT);
             boolean shared = origtype.startsWith("shared_");
             String type = shared ? origtype.substring(7) : origtype; //len(shared_)
@@ -874,7 +874,7 @@ public class Auxiliary {
             if (lv.size()>0)
             {
                 c.host.issueDeprecation("load_app_data(...) with arguments");
-                file = recognizeResource(lv.get(0).evalValue(c));
+                file = recognizeResource(lv.get(0).evalValue(c), false);
                 if (lv.size() > 1)
                 {
                     shared = lv.get(1).evalValue(c).getBoolean();
@@ -897,7 +897,7 @@ public class Auxiliary {
             if (lv.size()>1)
             {
                 c.host.issueDeprecation("store_app_data(...) with more than one argument");
-                file = recognizeResource(lv.get(1).evalValue(c));
+                file = recognizeResource(lv.get(1).evalValue(c), false);
                 if (lv.size() > 2)
                 {
                     shared = lv.get(2).evalValue(c).getBoolean();

src/main/java/carpet/script/bundled/FileModule.java

@@ -1,5 +1,7 @@
 package carpet.script.bundled;
 
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.nbt.NbtIo;
 import net.minecraft.nbt.PositionTracker;
 import net.minecraft.nbt.Tag;
 import net.minecraft.nbt.TagReaders;
@@ -60,7 +62,20 @@ public class FileModule extends Module
     }
 
     //copied private method from net.minecraft.nbt.NbtIo.read()
+    // to read non-compound tags - these won't be compressed
     public static Tag read(File file)
+    {
+        try
+        {
+            return NbtIo.readCompressed(file);
+        }
+        catch (IOException e)
+        {
+            try
+            {
+                return NbtIo.read(file);
+            }
+            catch (IOException ioException)
             {
                 try (DataInputStream dataInput_1 = new DataInputStream(new FileInputStream(file)))
                 {
@@ -80,6 +95,8 @@ public class FileModule extends Module
                 }
                 return null;
             }
+        }
+    }
 
     //copied private method from net.minecraft.nbt.NbtIo.write() and client method safe_write
     public static boolean write(Tag tag_1, File file)
@@ -87,7 +104,20 @@ public class FileModule extends Module
         File file_2 = new File(file.getAbsolutePath() + "_tmp");
         if (file_2.exists()) file_2.delete();
 
-        try(DataOutputStream dataOutputStream_1 = new DataOutputStream(new FileOutputStream(file_2)))
+        if (tag_1 instanceof CompoundTag)
+        {
+            try
+            {
+                NbtIo.writeCompressed((CompoundTag) tag_1, file_2);
+            }
+            catch (IOException e)
+            {
+                return false;
+            }
+        }
+        else
+        {
+            try (DataOutputStream dataOutputStream_1 = new DataOutputStream(new FileOutputStream(file_2)))
             {
                 dataOutputStream_1.writeByte(tag_1.getType());
                 if (tag_1.getType() != 0)
@@ -100,6 +130,7 @@ public class FileModule extends Module
             {
                 return false;
             }
+        }
         if (file.exists()) file.delete();
         if (!file.exists()) file_2.renameTo(file);
         return true;