Blocks which require tools to harvest don't drop in explosions

[buchwasa]

Issue description

When using an explosion (TNT, explodeA(), etc.) it doesn’t drop every block it should.

• Expected result: The explosion drops stone and other items that require tools to gather.
• Actual result: Only blocks that didn’t require tools to drop spawned.

Steps to reproduce the issue

1. Use any method of an explosion.
2. Check the results on the explosion.
3. Be amazed that only certain blocks dropped.

OS and versions

• PocketMine-MP: fa644edef3db4abaa050cb9cb0aaa94170e132df
• PHP: 7.2.1
• Server OS: Windows 10
• Game version: Both

Plugins

• Test on a clean server without plugins: is the issue reproducible without any plugins loaded?

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• ...

[Muqsit]

might be due to this https://github.com/pmmp/PocketMine-MP/blob/master/src/pocketmine/level/Explosion.php#L201

$air = ItemFactory::get(Item::AIR);
foreach($blocks as $block){
    foreach($block->getDrops($air) as $drop){...}
}

[buchwasa]

@Muqsit, a temporary fix is changing getDrops to getDropsForCompatibleTool() which doesn’t completely fix it.

[dktapps]

The problem here is that getDrops() requires a compatible tool. However circumventing the tool check is not a correct fix (this will cause tallgrass and other things to drop).

[TheAz928]

@dktapps why not add a new function like getSilkTouchDrops, $block->getExplosionDrops()?

[dktapps]

I would prefer not adding more methods for this if it can be reasonably avoided.

[dktapps]

It looks like we can fix this by having explosions pretend to be diamond pickaxes for Block->getDrops().

Out of all the blocks which require a tool to harvest, the vast majority require a pickaxe to drop. The only ones that don't which are currently implemented are these:

Cobweb requires 17, is insta break? 
Dead Bush requires 16, is insta break? 1
Double Tallgrass requires 16, is insta break? 1
Large Fern requires 16, is insta break? 1
Snow Block requires 2, is insta break? 
Snow Layer requires 2, is insta break? 
Fern requires 16, is insta break? 1
Tall Grass requires 16, is insta break? 1
Hanging Roots requires 16, is insta break? 1
Small Dripleaf requires 16, is insta break? 1

Basically all of these are "delicate" blocks which I wouldn't expect an explosion to drop the "compatible" drops for anyway. So it looks like there's no need to account for anything other than pickaxes.