The number reader methods in should raise a condition if not enough bytes could be read

[rapha]

Currently the various number reader methods defined in

std::rt::io::extensions::ReaderByteConversions

are based on read_u8_ and read_i8_ which simply return 0 if the byte could not be read. This means that the user can silently read bad values, e.g.

$ rusti
rusti> use std::rt::io::Reader; 
rusti> use std::rt::io::extensions::ReaderUtil;
rusti> use std::rt::io::extensions::ReaderByteConversions;
rusti> use std::rt::io::mem::MemReader; 
rusti> MemReader::new(~[1]).read_be_u32_()
16777216 

I suggest that a read_u8_ and read_i8_ should raise an EndOfFile, similarly to ReaderUtil::push_bytes, so the user can handle that case.

[alexcrichton]

I think that the actual bug here is that MemReader doesn't raise on io_error once None is returned.

[alexcrichton]

Closed by #11946