Empty contract should probably throw exceptions on calls

[hedgar2017]

Version Information

• vyper Version (output of vyper --version): 0.3.2

What's your issue about?

The empty contract has the following IR:

[seq, [deploy, 0, seq, 0]]

In Solidity it does, but any behavior is accepted here.
Such contracts may be treated as just one single fallback.
Please close the issue if so.

[hedgar2017]

That's right. In Yul an empty contract is just a revert:

object "test_1_deployed" {
        code {
            {
                /// @src 0:0:17  "contract test {..."
                revert(0, 0)
            }
        }
        data ".metadata" hex"a2646970667358221220c0ee3938739ac06f7623a04d58687a1d98be4d62f4fec897d0b8189d4d2b9a7564736f6c634300080d0033"
    }

[charles-cooper]

I'm not convinced this is a bug. immutables provide a way to create "data-only" contracts. for instance,

FOO: immutable(uint256)
@external
def __init__():
    FOO = 1

will deploy a contract with just the bytecode 0x0000000000000000000000000000000000000000000000000000000000000001. (Whereas if we inserted a fallback, it would have bunch of code in it besides the immutables). I'm not sure, but I feel like this may be useful in the future.

[charles-cooper]

this is completed (i believe as of #3496)