[move docs] Add enums to Move reference book (#68)

.github/workflows/test.yml

@@ -19,7 +19,7 @@ jobs:
         with:
           repo: MystenLabs/sui
           platform: ubuntu
-          version: mainnet
+          version: main
           cache: enable
 
       # Run the tests in every directory using the latest mainnet binary

packages/reference/Move.lock

@@ -0,0 +1,26 @@
+# @generated by Move, please check-in and do not edit manually.
+
+[move]
+version = 2
+manifest_digest = "868EC315260CC0A203EABE09C39C72CFDDB66DE119BDF7E24CE5EAABE30EFCC1"
+deps_digest = "F8BBB0CCB2491CA29A3DF03D6F92277A4F3574266507ACD77214D37ECA3F3082"
+dependencies = [
+  { name = "Sui" },
+]
+
+[[move.package]]
+name = "MoveStdlib"
+source = { git = "https://github.com/MystenLabs/sui.git", rev = "main", subdir = "crates/sui-framework/packages/move-stdlib" }
+
+[[move.package]]
+name = "Sui"
+source = { git = "https://github.com/MystenLabs/sui.git", rev = "main", subdir = "crates/sui-framework/packages/sui-framework" }
+
+dependencies = [
+  { name = "MoveStdlib" },
+]
+
+[move.toolchain-version]
+compiler-version = "1.27.0"
+edition = "2024.alpha"
+flavor = "sui"

packages/reference/Move.toml

@@ -1,6 +1,6 @@
 [package]
 name = "reference"
-edition = "2024.beta"
+edition = "2024.alpha"
 
 [dependencies.Sui]
 git = "https://github.com/MystenLabs/sui.git"

packages/reference/sources/abilities.move

@@ -4,11 +4,15 @@
 #[allow(unused_field)]
 module ref::abilities {
 
-// ANCHOR: annotating_structs
+// ANCHOR: annotating_datatypes
 public struct Ignorable has drop { f: u64 }
 public struct Pair has copy, drop, store { x: u64, y: u64 }
 public struct MyVec(vector<u64>) has copy, drop, store;
-// ANCHOR_END: annotating_structs
+
+public enum IgnorableEnum has drop { Variant }
+public enum PairEnum has copy, drop, store { Variant }
+public enum MyVecEnum { Variant } has copy, drop, store;
+// ANCHOR_END: annotating_datatypes
 
 // ANCHOR: conditional_abilities
 // public struct Cup<T> has copy, drop, store, key { item: T }

reference/src/abilities.md

@@ -98,17 +98,17 @@ All primitive, builtin types have `copy`, `drop`, and `store`.
 Note that none of the primitive types have `key`, meaning none of them can be used directly with
 storage operations.
 
-## Annotating Structs
+## Annotating Structs and Enums
 
-To declare that a `struct` has an ability, it is declared with `has <ability>` after the struct name
-and either before or after the fields. For example:
+To declare that a `struct` or `enum` has an ability, it is declared with `has <ability>` after the
+datatype name and either before or after the fields/variants. For example:
 
 ```move
-{{#include ../../packages/reference/sources/abilities.move:annotating_structs}}
+{{#include ../../packages/reference/sources/abilities.move:annotating_datatypes}}
 ```
 
-In this case: `Ignorable` has the `drop` ability. `Pair` and `MyVec` both have `copy`, `drop`, and
-`store`.
+In this case: `Ignorable*` has the `drop` ability. `Pair*` and `MyVec*` both have `copy`, `drop`,
+and `store`.
 
 All of these abilities have strong guarantees over these gated operations. The operation can be
 performed on the value only if it has that ability; even if the value is deeply nested inside of
@@ -124,6 +124,16 @@ reachability rules for the abilities given above. If a struct is declared with t
 - `key`, all fields must have `store`.
   - `key` is the only ability currently that doesn’t require itself.
 
+An enum can have any of these abilities with the exception of `key`, which enums cannot have because
+they cannot be top-level values (objects) in storage. The same rules apply to fields of enum
+variants as they do for struct fields though. In particular, if an enum is declared with the
+ability...
+
+- `copy`, all fields of all variants must have `copy`.
+- `drop`, all fields of all variants must have `drop`.
+- `store`, all fields of all variants must have `store`.
+- `key`, is not allowed on enums as previously mentioned.
+
 For example:
 
 ```move
@@ -133,6 +143,11 @@ public struct NoAbilities {}
 public struct WantsCopy has copy {
     f: NoAbilities, // ERROR 'NoAbilities' does not have 'copy'
 }
+
+public enum WantsCopyEnum has copy {
+    Variant1
+    Variant2(NoAbilities), // ERROR 'NoAbilities' does not have 'copy'
+}
 ```
 
 and similarly:
@@ -144,6 +159,11 @@ public struct NoAbilities {}
 public struct MyData has key {
     f: NoAbilities, // Error 'NoAbilities' does not have 'store'
 }
+
+public struct MyDataEnum has store {
+    Variant1,
+    Variant2(NoAbilities), // Error 'NoAbilities' does not have 'store'
+}
 ```
 
 ## Conditional Abilities and Generic Types