Panic ast.Type *ast.Interface not expected

[MariusVanDerWijden]

I get the following error during code generation.

panic: ast type '*ast.InterfaceType' not expected

goroutine 1 [running]:
main.(*env).parseASTFieldType(0xc000129e28, 0xc000016570, 0xf, 0x0, 0x0, 0x5e4a08, 0xc00000c2a0, 0x0, 0xc000129b40, 0x412fbb)
        /home/matematik/ethereum/fastssz/sszgen/main.go:1043 +0x14cc
main.(*env).encodeItem(0xc000129e28, 0xc000016570, 0xf, 0x0, 0x0, 0xc000110c00, 0x4, 0x8)
        /home/matematik/ethereum/fastssz/sszgen/main.go:825 +0x34f
main.(*env).generateIR(0xc000129e28, 0xc000010d50, 0xc000129dc8)
        /home/matematik/ethereum/fastssz/sszgen/main.go:794 +0x835
main.encode(0x7ffefa5f62c0, 0x7, 0x6eb740, 0x0, 0x0, 0x0, 0x0, 0x6eb740, 0x0, 0x0, ...)
        /home/matematik/ethereum/fastssz/sszgen/main.go:95 +0x205
main.main()
        /home/matematik/ethereum/fastssz/sszgen/main.go:43 +0x3cb
exit status 2

command: go run ~/ethereum/fastssz/sszgen/*.go --path ./types project: https://github.com/MariusVanDerWijden/go-eth2lc

This is probably due to some nested types right? Do all types need to be available in the project or can you import types from other projects?

[MariusVanDerWijden]

Ahh I had an interface defined in one of the files

type Serialize interface {
    Marshal() []byte
}

Which broke code generation, might be cool to just ignore these.

[ferranbt]

Please check #53, it should fix the issue.

Besides, I would recommend you to use the '--objs' flag to filter for specific objects and skip everything else. Is there any reason why you would use your own Serialize interface instead of using the Marshaler interface from the library?

[MariusVanDerWijden]

Nah, I already removed the Serialize interface, was just an artifact from before

[MariusVanDerWijden]

The only problem I have right now is that I cannot ssz a common.Hash which is a type alias for [32]byte{} from geth

[ferranbt]

In the spectests there is an example of an external reference, you can use --include to link the path of the common package such that that sszgen knows the type.

[MariusVanDerWijden]

Now I get the following error:

panic: interface conversion: ast.Expr is *ast.Ident, not *ast.BasicLit

goroutine 1 [running]:
main.getObjLen(0xc000158db0, 0x0)
        /home/matematik/ethereum/fastssz/sszgen/main.go:890 +0x1a6
main.(*env).parseASTFieldType(0xc00013be28, 0xc000016258, 0x4, 0x0, 0x0, 0x5e4468, 0xc000158db0, 0xffffffffffffffff, 0x0, 0xc00019f9d0)
        /home/matematik/ethereum/fastssz/sszgen/main.go:930 +0x1051
main.(*env).encodeItem(0xc00013be28, 0xc000016258, 0x4, 0x0, 0x0, 0x0, 0x203000, 0x203000)
        /home/matematik/ethereum/fastssz/sszgen/main.go:825 +0x34f
main.(*env).parseASTFieldType(0xc00013be28, 0xc000016246, 0xa, 0x0, 0x0, 0x5e4b88, 0xc00000c0d8, 0x44a72c, 0x0, 0x5a1860)
        /home/matematik/ethereum/fastssz/sszgen/main.go:1034 +0x565
main.(*env).parseASTStructType(0xc00013be28, 0xc000016230, 0xb, 0xc00000c0f0, 0x6ec901, 0x5e4900, 0xc000062340)
        /home/matematik/ethereum/fastssz/sszgen/main.go:862 +0x168
main.(*env).encodeItem(0xc00013be28, 0xc000016230, 0xb, 0x0, 0x0, 0xc0001aa800, 0x0, 0x0)
        /home/matematik/ethereum/fastssz/sszgen/main.go:823 +0x12f
main.(*env).generateIR(0xc00013be28, 0xc0000762a0, 0xc00013bdc8)
        /home/matematik/ethereum/fastssz/sszgen/main.go:794 +0x835
main.encode(0x7fff8c0d026e, 0x10, 0x6eb740, 0x0, 0x0, 0x0, 0x0, 0xc000056340, 0x1, 0x1, ...)
        /home/matematik/ethereum/fastssz/sszgen/main.go:95 +0x205
main.main()
        /home/matematik/ethereum/fastssz/sszgen/main.go:43 +0x3cb
exit status 2

[MariusVanDerWijden]

It's because we use a constant instead of a literal in the type definition of common.Hash. E.g.

const HashLength = 32
type Hash [HashLength]byte

Don't know if that is something that the code generation should handle correctly. But I think the eth2 spec also uses constants for declaring the size of some fields so it might be needed, idk.

Edit. Just realized with ssz-size and ssz-max this is not needed