From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Sat, 23 Apr 2022 19:19:23 +0000 (+0100)
Subject: ambassador: Introduce dependency and make some traits delegatiable
X-Git-Tag: otter-1.1.0~412
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=commitdiff_plain;h=13805c8e7d9c0b96680be189cdbc48b5783baf49;p=otter.git

ambassador: Introduce dependency and make some traits delegatiable

fastsplit pieces are going to want to delegate everything.  Not only
is this a lot of typing, open-coding it risks bugs when new trait
methods are added.

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
---

diff --git a/Cargo.lock b/Cargo.lock
index 230f0354..27001818 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -287,6 +287,18 @@ dependencies = [
  "alloc-no-stdlib",
 ]
 
+[[package]]
+name = "ambassador"
+version = "0.3.0"
+source = "git+https://github.com/ijackson/ambassador?rev=e4775f906a7987b294e87c05ab1e923de0cf6a3a#e4775f906a7987b294e87c05ab1e923de0cf6a3a"
+dependencies = [
+ "bytemuck",
+ "itertools",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "ansi_term"
 version = "0.12.1"
@@ -529,6 +541,20 @@ name = "bytemuck"
 version = "1.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ee1e0e2125faccb856bf10b0a9dfa89c4c718d05ef85580dfefbdf1c422ef801"
+dependencies = [
+ "bytemuck_derive",
+]
+
+[[package]]
+name = "bytemuck_derive"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "562e382481975bc61d11275ac5e62a19abd00b0547d99516a415336f183dcd0e"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
 
 [[package]]
 name = "byteorder"
@@ -2637,6 +2663,7 @@ dependencies = [
 name = "otter"
 version = "1.0.0"
 dependencies = [
+ "ambassador",
  "anyhow",
  "async-condvar-fair",
  "backtrace",
diff --git a/Cargo.toml b/Cargo.toml
index 4d4ff58c..e45d45a8 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -89,6 +89,8 @@ vecdeque-stableix="1"
 xmlparser = "0.13"
 zip="0.6"
 
+ambassador = { version = "0.3", git = "https://github.com/ijackson/ambassador", rev="e4775f906a7987b294e87c05ab1e923de0cf6a3a" }
+
 async-condvar-fair = { version="0.2", features=["parking_lot_0_12"] }
 const-default = { version="1",    features=["derive"      ] }
 enum-map     = { version="2"    , features=["serde"       ] }
diff --git a/src/gamestate.rs b/src/gamestate.rs
index 4caeddec..0c67d77a 100644
--- a/src/gamestate.rs
+++ b/src/gamestate.rs
@@ -153,6 +153,7 @@ pub trait PieceXData: Downcast + Debug + Send + 'static {
 }
 impl_downcast!(PieceXData);
 
+#[ambassador::delegatable_trait]
 #[enum_dispatch]
 #[dyn_upcast]
 pub trait OutlineTrait: Debug + Sync + Send + 'static {
@@ -183,6 +184,7 @@ pub struct UoDescription {
   pub wrc: WhatResponseToClientOp,
 }
 
+#[ambassador::delegatable_trait]
 #[dyn_upcast]
 pub trait PieceBaseTrait: OutlineTrait + Send + Debug + 'static {
   /// By convention, occult face is nfaces-1
@@ -191,6 +193,7 @@ pub trait PieceBaseTrait: OutlineTrait + Send + Debug + 'static {
   fn itemname(&self) -> &str;
 }
 
+#[ambassador::delegatable_trait]
 #[typetag::serde] // usual variable: p
 pub trait PieceTrait: PieceBaseTrait + Send + Debug + 'static {
   fn add_ui_operations(&self, _y: ShowUnocculted,