Legacy API does not detect obvious errors

[jonathanfine]

In the legacy API each connection send() and sendreceive() starts with a drain(). This allows reporting of errors, as below.

>>> world.setBlock()
>>> world.conn.drain()
Drained Data: <Fail>
Last Message: <world.setBlock()>
>>> world.setBlock(50, 24, 3, 3, 3)
>>> world.conn.drain()
>>> world.setBlock(50, 24, 3, 23, 3)
>>> world.conn.drain()
Drained Data: <Fail>
Last Message: <world.setBlock(50,24,3,23,3)>

There are a number of things wrong with this. From my point of view the worst is that the legacy API relies on Minecraft to detect and report obvious errors in the input. I'd like to be able to develop and test code without having to run it against Minecraft to detect obvious problems.

Put another way, if an API call is made with obviously improper parameters I'd like Python to raise an exception and not pass the call on to Minecraft.

I am about to start writing a low-level API that provides this.

Here's something else that is wrong. No error from

>>> world.setBlock(50, 24, 3, 3.8)
>>> world.getBlock(50, 24, 3)
3