Add additional tests for CraftBlockData

src/main/java/org/bukkit/craftbukkit/block/data/CraftBlockData.java

@@ -352,6 +352,7 @@ public class CraftBlockData implements BlockData {
     private static final Map<Class<? extends Block>, Function<IBlockData, CraftBlockData>> MAP = new HashMap<>();
 
     static {
+        //<editor-fold desc="CraftBlockData Registration" defaultstate="collapsed">
         register(net.minecraft.server.BlockAnvil.class, org.bukkit.craftbukkit.block.impl.CraftAnvil::new);
         register(net.minecraft.server.BlockBanner.class, org.bukkit.craftbukkit.block.impl.CraftBanner::new);
         register(net.minecraft.server.BlockBannerWall.class, org.bukkit.craftbukkit.block.impl.CraftBannerWall::new);
@@ -460,6 +461,7 @@ public class CraftBlockData implements BlockData {
         register(net.minecraft.server.BlockWitherSkull.class, org.bukkit.craftbukkit.block.impl.CraftWitherSkull::new);
         register(net.minecraft.server.BlockWitherSkullWall.class, org.bukkit.craftbukkit.block.impl.CraftWitherSkullWall::new);
         register(net.minecraft.server.BlockWoodButton.class, org.bukkit.craftbukkit.block.impl.CraftWoodButton::new);
+        //</editor-fold>
     }
 
     private static void register(Class<? extends Block> nms, Function<IBlockData, CraftBlockData> bukkit) {

src/test/java/org/bukkit/BlockDataConversionTest.java

@@ -0,0 +1,38 @@
+package org.bukkit;
+
+import java.util.ArrayList;
+import java.util.List;
+import net.minecraft.server.Block;
+import net.minecraft.server.IBlockData;
+import net.minecraft.server.IRegistry;
+import org.bukkit.craftbukkit.block.data.CraftBlockData;
+import org.bukkit.support.AbstractTestingBase;
+import org.junit.Assert;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
+
+/**
+ * This test class ensures that all Blocks (as registered in IRegistry.BLOCK)
+ * can be converted into their CraftBlockData equivalent.
+ */
+@RunWith(Parameterized.class)
+public class BlockDataConversionTest extends AbstractTestingBase {
+
+    @Parameterized.Parameters(name = "{index}: {0}")
+    public static List<Object[]> args() {
+        List<Object[]> list = new ArrayList<>();
+        for (Block block : (Iterable<Block>) IRegistry.BLOCK) {
+            list.add(new Object[]{block.getBlockData()});
+        }
+        return list;
+    }
+
+    @Parameterized.Parameter(0) public IBlockData data;
+
+    @Test
+    public void testNotNull() {
+        Assert.assertNotNull(data);
+        Assert.assertNotNull(CraftBlockData.fromData(data));
+    }
+}

src/test/java/org/bukkit/PerMaterialTest.java

@@ -229,4 +229,11 @@ public class PerMaterialTest extends AbstractTestingBase {
             assertThat(material.getBlastResistance(), is(CraftMagicNumbers.getBlock(material).getDurability()));
         }
     }
+
+    @Test
+    public void testBlockDataCreation() {
+        if (material.isBlock()) {
+            assertNotNull(material.createBlockData());
+        }
+    }
 }