Fix crash when trying to play sounds for modded blocks with misconfigured sound events. Fixes #339

Author: Sollace

src/main/java/eu/ha3/presencefootsteps/world/AbstractSubstrateLookup.java

@@ -14,7 +14,10 @@ abstract class AbstractSubstrateLookup<T> implements Lookup<T> {
     protected abstract Identifier getId(T key);
 
     @Override
-    public SoundsKey getAssociation(T key, String substrate) {
+    public SoundsKey getAssociation(@Nullable T key, String substrate) {
+        if (key == null) {
+            return SoundsKey.UNASSIGNED;
+        }
         final Identifier id = getId(key);
         return getSubstrateMap(id, substrate).getOrDefault(id, SoundsKey.UNASSIGNED);
     }

src/main/java/eu/ha3/presencefootsteps/world/PrimitiveLookup.java

@@ -18,7 +18,7 @@ protected Identifier getId(SoundEvent key) {
     public void writeToReport(boolean full, JsonObjectWriter writer, Map<String, BlockSoundGroup> groups) throws IOException {
         writer.each(groups.values(), group -> {
             SoundEvent event = group.getStepSound();
-            if (full || !contains(event)) {
+            if (event != null && (full || !contains(event))) {
                 writer.field(getKey(group), getAssociation(event, getSubstrate(group)).raw());
             }
         });