Program: 134171
Project: 134171
Buggy source:
public static boolean isIgnitable(Player player,Block block){
  Material[] overwriteable={Material.SAPLING,Material.LONG_GRASS,Material.DEAD_BUSH,Material.YELLOW_FLOWER,Material.RED_ROSE,Material.BROWN_MUSHROOM,Material.RED_MUSHROOM,Material.FIRE,Material.SNOW,Material.TORCH};
  if (Arrays.asList(overwriteable).contains(block.getType())) {
    return true;
  }
 else   if (block.getType() != Material.AIR) {
    return false;
  }
  Material[] ignitable={Material.BEDROCK,Material.BOOKSHELF,Material.BRICK,Material.CLAY,Material.CLAY_BRICK,Material.COAL_ORE,Material.COBBLESTONE,Material.DIAMOND_ORE,Material.DIAMOND_BLOCK,Material.DIRT,Material.ENDER_STONE,Material.GLOWING_REDSTONE_ORE,Material.GOLD_BLOCK,Material.GRAVEL,Material.GRASS,Material.HUGE_MUSHROOM_1,Material.HUGE_MUSHROOM_2,Material.LAPIS_BLOCK,Material.LAPIS_ORE,Material.LOG,Material.MOSSY_COBBLESTONE,Material.MYCEL,Material.NETHER_BRICK,Material.NETHERRACK,Material.OBSIDIAN,Material.REDSTONE_ORE,Material.SAND,Material.SANDSTONE,Material.SMOOTH_BRICK,Material.STONE,Material.SOUL_SAND,Material.WOOD,Material.WOOL,Material.LEAVES,Material.MELON_BLOCK,Material.PUMPKIN,Material.JACK_O_LANTERN,Material.NOTE_BLOCK,Material.GLOWSTONE,Material.IRON_BLOCK,Material.DISPENSER,Material.SPONGE,Material.IRON_ORE,Material.GOLD_ORE,Material.COAL_BLOCK,Material.WORKBENCH,Material.HAY_BLOCK,Material.REDSTONE_LAMP_OFF,Material.REDSTONE_LAMP_ON,Material.EMERALD_ORE,Material.EMERALD_BLOCK,Material.REDSTONE_BLOCK,Material.QUARTZ_BLOCK,Material.QUARTZ_ORE,Material.STAINED_CLAY,Material.HARD_CLAY};
  Block belowblock=block.getRelative(BlockFace.DOWN);
  if (Arrays.asList(ignitable).contains(belowblock.getType())) {
    return true;
  }
  return false;
}

Fixed version (ground truth):
public static boolean isIgnitable(Player player,Block block){
  Material[] overwriteable={Material.SAPLING,Material.LONG_GRASS,Material.THIN_GLASS,Material.DEAD_BUSH,Material.YELLOW_FLOWER,Material.RED_ROSE,Material.BROWN_MUSHROOM,Material.RED_MUSHROOM,Material.FIRE,Material.SNOW,Material.TORCH};
  if (Arrays.asList(overwriteable).contains(block.getType())) {
    return true;
  }
 else   if (block.getType() != Material.AIR) {
    return false;
  }
  Material[] ignitable={Material.BEDROCK,Material.BOOKSHELF,Material.BRICK,Material.CLAY,Material.CLAY_BRICK,Material.COAL_ORE,Material.COBBLESTONE,Material.DIAMOND_ORE,Material.DIAMOND_BLOCK,Material.DIRT,Material.ENDER_STONE,Material.GLOWING_REDSTONE_ORE,Material.GOLD_BLOCK,Material.GRAVEL,Material.GRASS,Material.HUGE_MUSHROOM_1,Material.HUGE_MUSHROOM_2,Material.LAPIS_BLOCK,Material.LAPIS_ORE,Material.LOG,Material.MOSSY_COBBLESTONE,Material.MYCEL,Material.NETHER_BRICK,Material.NETHERRACK,Material.OBSIDIAN,Material.REDSTONE_ORE,Material.SAND,Material.SANDSTONE,Material.SMOOTH_BRICK,Material.STONE,Material.SOUL_SAND,Material.WOOD,Material.WOOL,Material.LEAVES,Material.LEAVES_2,Material.MELON_BLOCK,Material.PUMPKIN,Material.JACK_O_LANTERN,Material.NOTE_BLOCK,Material.GLOWSTONE,Material.IRON_BLOCK,Material.DISPENSER,Material.SPONGE,Material.IRON_ORE,Material.GOLD_ORE,Material.COAL_BLOCK,Material.WORKBENCH,Material.HAY_BLOCK,Material.REDSTONE_LAMP_OFF,Material.REDSTONE_LAMP_ON,Material.EMERALD_ORE,Material.EMERALD_BLOCK,Material.REDSTONE_BLOCK,Material.QUARTZ_BLOCK,Material.QUARTZ_ORE,Material.STAINED_CLAY,Material.HARD_CLAY};
  Block belowblock=block.getRelative(BlockFace.DOWN);
  if (Arrays.asList(ignitable).contains(belowblock.getType())) {
    return true;
  }
  return false;
}