twilight forest conflict detector fix

src/main/java/com/falsepattern/endlessids/mixin/mixins/common/twilightforest/TFBiomeBaseMixin.java

@@ -1,12 +1,18 @@
 package com.falsepattern.endlessids.mixin.mixins.common.twilightforest;
 
+import com.falsepattern.endlessids.PlaceholderBiome;
 import com.falsepattern.endlessids.constants.ExtendedConstants;
 import com.falsepattern.endlessids.constants.VanillaConstants;
+import lombok.val;
 import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Constant;
 import org.spongepowered.asm.mixin.injection.ModifyConstant;
+import org.spongepowered.asm.mixin.injection.Redirect;
 import twilightforest.biomes.TFBiomeBase;
 
+import net.minecraft.world.biome.BiomeGenBase;
+
 @Mixin(value = TFBiomeBase.class,
        remap = false)
 public abstract class TFBiomeBaseMixin {
@@ -16,4 +22,19 @@ public abstract class TFBiomeBaseMixin {
     private static int extendIDs(int constant) {
         return ExtendedConstants.biomeIDCount;
     }
+
+    @Redirect(method = "isConflictAtBiomeID",
+              at = @At(value = "INVOKE",
+                       target = "Lnet/minecraft/world/biome/BiomeGenBase;getBiome(I)Lnet/minecraft/world/biome/BiomeGenBase;",
+                       remap = true),
+              require = 1)
+    private static BiomeGenBase ignorePlaceholders(int id) {
+        val biome = BiomeGenBase.getBiome(id);
+        if (biome instanceof PlaceholderBiome) {
+            BiomeGenBase.getBiomeGenArray()[id] = null;
+            return null;
+        } else {
+            return biome;
+        }
+    }
 }