Deprecate enum_behaviour

Cargo.lock

@@ -393,7 +393,7 @@ dependencies = [
  "eth2",
  "eth2_hashing",
  "eth2_ssz",
- "eth2_ssz_derive",
+ "eth2_ssz_derive 0.3.0",
  "eth2_ssz_types",
  "execution_layer",
  "exit-future",
@@ -714,7 +714,7 @@ version = "0.1.0"
 dependencies = [
  "eth2_hashing",
  "eth2_ssz",
- "eth2_ssz_derive",
+ "eth2_ssz_derive 0.3.0",
  "eth2_ssz_types",
  "ethereum-types 0.12.1",
  "quickcheck",
@@ -1498,7 +1498,7 @@ dependencies = [
  "compare_fields_derive",
  "derivative",
  "eth2_ssz",
- "eth2_ssz_derive",
+ "eth2_ssz_derive 0.3.0",
  "ethereum-types 0.12.1",
  "fork_choice",
  "fs2",
@@ -1661,7 +1661,7 @@ dependencies = [
  "eth1_test_rig",
  "eth2",
  "eth2_ssz",
- "eth2_ssz_derive",
+ "eth2_ssz_derive 0.3.0",
  "execution_layer",
  "futures",
  "hex",
@@ -1705,7 +1705,7 @@ dependencies = [
  "eth2_keystore",
  "eth2_serde_utils",
  "eth2_ssz",
- "eth2_ssz_derive",
+ "eth2_ssz_derive 0.3.0",
  "futures",
  "futures-util",
  "libsecp256k1",
@@ -1821,7 +1821,7 @@ dependencies = [
 name = "eth2_ssz"
 version = "0.4.1"
 dependencies = [
- "eth2_ssz_derive",
+ "eth2_ssz_derive 0.4.0",
  "ethereum-types 0.12.1",
  "itertools",
  "smallvec",
@@ -1829,7 +1829,9 @@ dependencies = [
 
 [[package]]
 name = "eth2_ssz_derive"
-version = "0.3.1"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "635b86d2c941bb71e7419a571e1763d65c93e51a1bafc400352e3bef6ff59fc9"
 dependencies = [
  "darling",
  "proc-macro2",
@@ -1837,6 +1839,17 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "eth2_ssz_derive"
+version = "0.4.0"
+dependencies = [
+ "darling",
+ "eth2_ssz",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "eth2_ssz_types"
 version = "0.2.2"
@@ -2240,7 +2253,7 @@ version = "0.1.0"
 dependencies = [
  "beacon_chain",
  "eth2_ssz",
- "eth2_ssz_derive",
+ "eth2_ssz_derive 0.3.0",
  "proto_array",
  "slog",
  "state_processing",
@@ -3660,7 +3673,7 @@ dependencies = [
  "discv5",
  "error-chain",
  "eth2_ssz",
- "eth2_ssz_derive",
+ "eth2_ssz_derive 0.3.0",
  "eth2_ssz_types",
  "exit-future",
  "fnv",
@@ -4420,7 +4433,7 @@ dependencies = [
  "bitvec 1.0.1",
  "derivative",
  "eth2_ssz",
- "eth2_ssz_derive",
+ "eth2_ssz_derive 0.3.0",
  "itertools",
  "lazy_static",
  "lighthouse_metrics",
@@ -5007,7 +5020,7 @@ name = "proto_array"
 version = "0.2.0"
 dependencies = [
  "eth2_ssz",
- "eth2_ssz_derive",
+ "eth2_ssz_derive 0.3.0",
  "serde",
  "serde_derive",
  "serde_yaml",
@@ -5980,7 +5993,7 @@ dependencies = [
  "bincode",
  "byteorder",
  "eth2_ssz",
- "eth2_ssz_derive",
+ "eth2_ssz_derive 0.3.0",
  "filesystem",
  "flate2",
  "lazy_static",
@@ -6267,7 +6280,7 @@ dependencies = [
  "env_logger 0.9.0",
  "eth2_hashing",
  "eth2_ssz",
- "eth2_ssz_derive",
+ "eth2_ssz_derive 0.3.0",
  "eth2_ssz_types",
  "int_to_bytes",
  "integer-sqrt",
@@ -6309,7 +6322,7 @@ dependencies = [
  "db-key",
  "directory",
  "eth2_ssz",
- "eth2_ssz_derive",
+ "eth2_ssz_derive 0.3.0",
  "itertools",
  "lazy_static",
  "leveldb",
@@ -6946,7 +6959,7 @@ dependencies = [
  "beacon_chain",
  "eth2_hashing",
  "eth2_ssz",
- "eth2_ssz_derive",
+ "eth2_ssz_derive 0.3.0",
  "ethereum-types 0.12.1",
  "rand 0.8.5",
  "smallvec",
@@ -7085,7 +7098,7 @@ dependencies = [
  "eth2_interop_keypairs",
  "eth2_serde_utils",
  "eth2_ssz",
- "eth2_ssz_derive",
+ "eth2_ssz_derive 0.3.0",
  "eth2_ssz_types",
  "ethereum-types 0.12.1",
  "hex",

consensus/ssz/Cargo.toml

@@ -10,7 +10,7 @@ license = "Apache-2.0"
 name = "ssz"
 
 [dev-dependencies]
-eth2_ssz_derive = "0.3.1"
+eth2_ssz_derive = "0.4.0"
 
 [dependencies]
 ethereum-types = "0.12.1"

consensus/ssz/tests/tests.rs

@@ -387,7 +387,7 @@ mod derive_macro {
     }
 
     #[derive(PartialEq, Debug, Encode, Decode)]
-    #[ssz(enum_behaviour = "union")]
+    #[ssz(union)]
     enum TwoFixedUnion {
         U8(u8),
         U16(u16),
@@ -422,16 +422,9 @@ mod derive_macro {
         b: u8,
     }
 
-    #[derive(PartialEq, Debug, Encode)]
-    #[ssz(enum_behaviour = "transparent")]
-    enum TwoVariableTrans {
-        A(VariableA),
-        B(VariableB),
-    }
-
     #[derive(PartialEq, Debug, Encode)]
     #[ssz(transparent)]
-    enum TwoVariableTransDirectTag {
+    enum TwoVariableTrans {
         A(VariableA),
         B(VariableB),
     }
@@ -441,16 +434,9 @@ mod derive_macro {
         a: TwoVariableTrans,
     }
 
-    #[derive(PartialEq, Debug, Encode, Decode)]
-    #[ssz(enum_behaviour = "union")]
-    enum TwoVariableUnion {
-        A(VariableA),
-        B(VariableB),
-    }
-
     #[derive(PartialEq, Debug, Encode, Decode)]
     #[ssz(union)]
-    enum TwoVariableUnionDirectTag {
+    enum TwoVariableUnion {
         A(VariableA),
         B(VariableB),
     }
@@ -509,7 +495,7 @@ mod derive_macro {
     }
 
     #[derive(PartialEq, Debug, Encode, Decode)]
-    #[ssz(enum_behaviour = "union")]
+    #[ssz(union)]
     enum TwoVecUnion {
         A(Vec<u8>),
         B(Vec<u8>),

consensus/ssz_derive/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "eth2_ssz_derive"
-version = "0.3.1"
+version = "0.4.0"
 authors = ["Paul Hauner <paul@sigmaprime.io>"]
 edition = "2021"
 description = "Procedural derive macros to accompany the eth2_ssz crate."
@@ -17,3 +17,4 @@ quote = "1.0.7"
 darling = "0.13.0"
 
 [dev-dependencies]
+eth2_ssz = "0.4.1"

consensus/ssz_derive/src/lib.rs

@@ -1,7 +1,127 @@
 #![recursion_limit = "256"]
 //! Provides procedural derive macros for the `Encode` and `Decode` traits of the `eth2_ssz` crate.
 //!
-//! Supports field attributes, see each derive macro for more information.
+//! ## Struct Attributes
+//!
+//! The following struct attributes are available:
+//!
+//! - `#[ssz(union)]`
+//!     - For `enum`, implements `ssz::Encode` and `ssz::Decode` such that the union variant is
+//!       encoded as a single byte in the SSZ vector.
+//!     - Not supported for `struct`.
+//! - `#[ssz(transparent)]`
+//!     - For `enum`, implements `ssz::Encode` such that the `enum` is ignored. `ssz::Decode` is not
+//!       supported.
+//!     - For `struct`, implements `ssz::Encode` and `ssz::Decode` such that the outermost `struct`
+//!       is ignored for encoding and decoding. This is useful for new-type wrappers. The `struct`
+//!       must have exactly one non-skipped field.
+//!
+//! ## Field Attributes
+//!
+//! The following field attributes are available:
+//!
+//! - `#[ssz(with = "module")]`: uses the methods in `module` to implement `ssz::Encode` or
+//!   `ssz::Decode`. This is useful when it's not possible to create an `impl` for that type
+//!   (perhaps it is defined in another crate).
+//! - `#[ssz(skip_serializing)]`: this field will not be included in the serialized SSZ vector.
+//! - `#[ssz(skip_deserializing)]`: this field will not be expected to be included in the serialized
+//!   SSZ vector and it will be initialized from a `Default` implementation.
+//!
+//! ## Examples
+//!
+//! ### Structs
+//!
+//! ```rust
+//! use ssz::{Encode, Decode};
+//! use ssz_derive::{Encode, Decode};
+//!
+//! /// Represented as an SSZ "list" wrapped in an SSZ "container".
+//! #[derive(Debug, PartialEq, Encode, Decode)]
+//! struct TypicalStruct {
+//!     foo: Vec<u8>
+//! }
+//!
+//! assert_eq!(
+//!     TypicalStruct { foo: vec![42] }.as_ssz_bytes(),
+//!     vec![4, 0, 0, 0, 42]
+//! );
+//!
+//! assert_eq!(
+//!     TypicalStruct::from_ssz_bytes(&[4, 0, 0, 0, 42]).unwrap(),
+//!     TypicalStruct { foo: vec![42] },
+//! );
+//!
+//! /// Represented as an SSZ "list" *without* an SSZ "container".
+//! #[derive(Encode, Decode)]
+//! #[ssz(transparent)]
+//! struct NewType {
+//!     foo: Vec<u8>
+//! }
+//!
+//! assert_eq!(
+//!     NewType { foo: vec![42] }.as_ssz_bytes(),
+//!     vec![42]
+//! );
+//!
+//! /// Represented as an SSZ "list" *without* an SSZ "container". The `bar` byte is ignored.
+//! #[derive(Debug, PartialEq, Encode, Decode)]
+//! #[ssz(transparent)]
+//! struct NewTypeSkippedField {
+//!     foo: Vec<u8>,
+//!     #[ssz(skip_serializing, skip_deserializing)]
+//!     bar: u8,
+//! }
+//!
+//! assert_eq!(
+//!     NewTypeSkippedField { foo: vec![42], bar: 99 }.as_ssz_bytes(),
+//!     vec![42]
+//! );
+//! assert_eq!(
+//!     NewTypeSkippedField::from_ssz_bytes(&[42]).unwrap(),
+//!     NewTypeSkippedField { foo: vec![42], bar: 0 }
+//! );
+//! ```
+//!
+//! ### Enums
+//!
+//! ```rust
+//! use ssz::{Encode, Decode};
+//! use ssz_derive::{Encode, Decode};
+//!
+//! /// Represented as an SSZ "union".
+//! #[derive(Debug, PartialEq, Encode, Decode)]
+//! #[ssz(union)]
+//! enum UnionEnum {
+//!     Foo(u8),
+//!     Bar(u8),
+//! }
+//!
+//! assert_eq!(
+//!     UnionEnum::Foo(42).as_ssz_bytes(),
+//!     vec![0, 42]
+//! );
+//! assert_eq!(
+//!     UnionEnum::from_ssz_bytes(&[1, 42]).unwrap(),
+//!     UnionEnum::Bar(42),
+//! );
+//!
+//! /// Represented as only the value in the enum variant.
+//! #[derive(Debug, PartialEq, Encode)]
+//! #[ssz(transparent)]
+//! enum TransparentEnum {
+//!     Foo(u8),
+//!     Bar(Vec<u8>),
+//! }
+//!
+//! assert_eq!(
+//!     TransparentEnum::Foo(42).as_ssz_bytes(),
+//!     vec![42]
+//! );
+//! assert_eq!(
+//!     TransparentEnum::Bar(vec![42, 42]).as_ssz_bytes(),
+//!     vec![42, 42]
+//! );
+//! ```
 
 use darling::{FromDeriveInput, FromMeta};
 use proc_macro::TokenStream;
@@ -13,11 +133,8 @@ use syn::{parse_macro_input, DataEnum, DataStruct, DeriveInput, Ident};
 /// extensions).
 const MAX_UNION_SELECTOR: u8 = 127;
 
-const ENUM_TRANSPARENT: &str = "transparent";
-const ENUM_UNION: &str = "union";
-const ENUM_VARIANTS: &[&str] = &[ENUM_TRANSPARENT, ENUM_UNION];
 const NO_ENUM_BEHAVIOUR_ERROR: &str = "enums require a \"transparent\" or \"union\" attribute, \
-    e.g., #[ssz(transparent)]";
+    e.g., #[ssz(transparent)] or #[ssz(union)]";
 
 #[derive(Debug, FromDeriveInput)]
 #[darling(attributes(ssz))]
@@ -54,18 +171,11 @@ impl Config {
             (false, false, None) => EnumBehaviour::Unspecified,
             (true, false, None) => EnumBehaviour::Transparent,
             (false, true, None) => EnumBehaviour::Union,
-            (false, false, Some(behaviour_string)) => match behaviour_string.as_ref() {
-                ENUM_TRANSPARENT => EnumBehaviour::Transparent,
-                ENUM_UNION => EnumBehaviour::Union,
-                other => panic!(
-                    "{} is an invalid enum_behaviour, use either {:?}",
-                    other, ENUM_VARIANTS
-                ),
-            },
             (true, true, _) => panic!("cannot provide both \"transparent\" and \"union\""),
-            (_, _, Some(_)) => {
+            (_, _, Some(_)) => panic!(
-                panic!("\"enum_behaviour\" cannot be used with \"transparent\" or \"union\"")
+                "the \"enum_behaviour\" attribute has been removed, please use \
-            }
+                either #[ssz(transparent)] or #[ssz(union)] instead"
+            ),
         };
 
         // Don't allow `enum_behaviour` for structs.
@@ -470,8 +580,7 @@ pub fn ssz_decode_derive(input: TokenStream) -> TokenStream {
         syn::Data::Enum(s) => match config.enum_behaviour {
             EnumBehaviour::Union => ssz_decode_derive_enum_union(&item, s),
             EnumBehaviour::Transparent => panic!(
-                "Decode cannot be derived for enum_behaviour \"{}\", only \"{}\" is valid.",
+                "Decode cannot be derived for enum_behaviour \"transparent\", only \"union\" is valid."
-                ENUM_TRANSPARENT, ENUM_UNION
             ),
             EnumBehaviour::Unspecified => panic!("{}", NO_ENUM_BEHAVIOUR_ERROR),
         },