upgrade to syn 2.x

Signed-off-by: Jason Volk <jason@zemos.net>

Cargo.lock

@@ -731,9 +731,10 @@ dependencies = [
 name = "conduit_macros"
 version = "0.4.5"
 dependencies = [
+ "itertools 0.13.0",
  "proc-macro2",
  "quote",
- "syn 1.0.109",
+ "syn 2.0.71",
 ]
 
 [[package]]

Cargo.toml

@@ -426,7 +426,7 @@ default-features = false
 version = "0.1"
 
 [workspace.dependencies.syn]
-version = "1.0"
+version = "2.0"
 features = ["full", "extra-traits"]
 
 [workspace.dependencies.quote]

src/core/info/cargo.rs

@@ -16,19 +16,19 @@ use crate::Result;
 
 #[cargo_manifest]
 const WORKSPACE_MANIFEST: &'static str = ();
-#[cargo_manifest("macros")]
+#[cargo_manifest(crate = "macros")]
 const MACROS_MANIFEST: &'static str = ();
-#[cargo_manifest("core")]
+#[cargo_manifest(crate = "core")]
 const CORE_MANIFEST: &'static str = ();
-#[cargo_manifest("database")]
+#[cargo_manifest(crate = "database")]
 const DATABASE_MANIFEST: &'static str = ();
-#[cargo_manifest("service")]
+#[cargo_manifest(crate = "service")]
 const SERVICE_MANIFEST: &'static str = ();
-#[cargo_manifest("admin")]
+#[cargo_manifest(crate = "admin")]
 const ADMIN_MANIFEST: &'static str = ();
-#[cargo_manifest("router")]
+#[cargo_manifest(crate = "router")]
 const ROUTER_MANIFEST: &'static str = ();
-#[cargo_manifest("main")]
+#[cargo_manifest(crate = "main")]
 const MAIN_MANIFEST: &'static str = ();
 
 /// Processed list of features access all project crates. This is generated from

src/macros/Cargo.toml

@@ -18,6 +18,7 @@ proc-macro = true
 syn.workspace = true
 quote.workspace = true
 proc-macro2.workspace = true
+itertools.workspace = true
 
 [lints]
 workspace = true

src/macros/admin.rs

@@ -1,17 +1,15 @@
+use itertools::Itertools;
 use proc_macro::{Span, TokenStream};
 use proc_macro2::TokenStream as TokenStream2;
-use quote::quote;
-use syn::{parse_macro_input, AttributeArgs, Fields, Ident, ItemEnum, Variant};
+use quote::{quote, ToTokens};
+use syn::{Error, Fields, Ident, ItemEnum, Meta, Variant};
 
-use crate::utils::camel_to_snake_string;
+use crate::{utils::camel_to_snake_string, Result};
 
-pub(super) fn command_dispatch(args: TokenStream, input_: TokenStream) -> TokenStream {
-	let input = input_.clone();
-	let item = parse_macro_input!(input as ItemEnum);
-	let _args = parse_macro_input!(args as AttributeArgs);
-	let arm = item.variants.iter().map(dispatch_arm);
-	let name = item.ident;
-	let q = quote! {
+pub(super) fn command_dispatch(item: ItemEnum, _args: &[Meta]) -> Result<TokenStream> {
+	let name = &item.ident;
+	let arm: Vec<TokenStream2> = item.variants.iter().map(dispatch_arm).try_collect()?;
+	let switch = quote! {
 		pub(super) async fn process(command: #name, body: Vec<&str>) -> Result<RoomMessageEventContent> {
 			use #name::*;
 			#[allow(non_snake_case)]
@@ -21,14 +19,17 @@ pub(super) fn command_dispatch(args: TokenStream, input_: TokenStream) -> TokenS
 		}
 	};
 
-	[input_, q.into()].into_iter().collect::<TokenStream>()
+	Ok([item.into_token_stream(), switch]
+		.into_iter()
+		.collect::<TokenStream2>()
+		.into())
 }
 
-fn dispatch_arm(v: &Variant) -> TokenStream2 {
+fn dispatch_arm(v: &Variant) -> Result<TokenStream2> {
 	let name = &v.ident;
 	let target = camel_to_snake_string(&format!("{name}"));
 	let handler = Ident::new(&target, Span::call_site().into());
-	match &v.fields {
+	let res = match &v.fields {
 		Fields::Named(fields) => {
 			let field = fields.named.iter().filter_map(|f| f.ident.as_ref());
 			let arg = field.clone();
@@ -37,7 +38,9 @@ fn dispatch_arm(v: &Variant) -> TokenStream2 {
 			}
 		},
 		Fields::Unnamed(fields) => {
-			let field = &fields.unnamed.first().expect("one field");
+			let Some(ref field) = fields.unnamed.first() else {
+				return Err(Error::new(Span::call_site().into(), "One unnamed field required"));
+			};
 			quote! {
 				#name ( #field ) => Box::pin(#handler::process(#field, body)).await?,
 			}
@@ -47,5 +50,7 @@ fn dispatch_arm(v: &Variant) -> TokenStream2 {
 				#name => Box::pin(#handler(&body)).await?,
 			}
 		},
-	}
+	};
+
+	Ok(res)
 }

src/macros/cargo.rs

@@ -1,39 +1,34 @@
 use std::{fs::read_to_string, path::PathBuf};
 
-use proc_macro::TokenStream;
+use proc_macro::{Span, TokenStream};
 use quote::quote;
-use syn::{parse_macro_input, AttributeArgs, ItemConst, Lit, NestedMeta};
+use syn::{Error, ItemConst, Meta};
 
-pub(super) fn manifest(args: TokenStream, item: TokenStream) -> TokenStream {
-	let item = parse_macro_input!(item as ItemConst);
-	let args = parse_macro_input!(args as AttributeArgs);
-	let member = args.into_iter().find_map(|arg| {
-		let NestedMeta::Lit(arg) = arg else {
-			return None;
-		};
-		let Lit::Str(arg) = arg else {
-			return None;
-		};
-		Some(arg.value())
-	});
+use crate::{utils, Result};
 
-	let path = manifest_path(member.as_deref());
+pub(super) fn manifest(item: ItemConst, args: &[Meta]) -> Result<TokenStream> {
+	let member = utils::get_named_string(args, "crate");
+	let path = manifest_path(member.as_deref())?;
 	let manifest = read_to_string(&path).unwrap_or_default();
-
-	let name = item.ident;
 	let val = manifest.as_str();
+	let name = item.ident;
 	let ret = quote! {
 		const #name: &'static str = #val;
 	};
 
-	ret.into()
+	Ok(ret.into())
 }
 
 #[allow(clippy::option_env_unwrap)]
-fn manifest_path(member: Option<&str>) -> PathBuf {
-	let mut path: PathBuf = option_env!("CARGO_MANIFEST_DIR")
-		.expect("missing CARGO_MANIFEST_DIR in environment")
-		.into();
+fn manifest_path(member: Option<&str>) -> Result<PathBuf> {
+	let Some(path) = option_env!("CARGO_MANIFEST_DIR") else {
+		return Err(Error::new(
+			Span::call_site().into(),
+			"missing CARGO_MANIFEST_DIR in environment",
+		));
+	};
+
+	let mut path: PathBuf = path.into();
 
 	// conduwuit/src/macros/ -> conduwuit/src/
 	path.pop();
@@ -47,5 +42,6 @@ fn manifest_path(member: Option<&str>) -> PathBuf {
 	}
 
 	path.push("Cargo.toml");
-	path
+
+	Ok(path)
 }

src/macros/debug.rs

@@ -1,13 +1,12 @@
 use std::cmp;
 
 use proc_macro::TokenStream;
-use syn::{parse_macro_input, AttributeArgs, Item};
+use quote::ToTokens;
+use syn::{Item, Meta};
 
-pub(super) fn recursion_depth(args: TokenStream, item_: TokenStream) -> TokenStream {
-	let item = item_.clone();
-	let item = parse_macro_input!(item as Item);
-	let _args = parse_macro_input!(args as AttributeArgs);
+use crate::Result;
 
+pub(super) fn recursion_depth(item: Item, _args: &[Meta]) -> Result<TokenStream> {
 	let mut best: usize = 0;
 	let mut count: usize = 0;
 	// think you'd find a fancy recursive ast visitor? think again
@@ -24,5 +23,5 @@ pub(super) fn recursion_depth(args: TokenStream, item_: TokenStream) -> TokenStr
 	println!("DEPTH: {best}");
 	println!("LENGTH: {count}");
 
-	item_
+	Ok(item.into_token_stream().into())
 }

src/macros/implement.rs

@@ -1,23 +1,26 @@
 use proc_macro::TokenStream;
-use quote::{quote, ToTokens};
-use syn::{parse_macro_input, AttributeArgs, ItemFn, Meta, NestedMeta};
+use quote::quote;
+use syn::{ItemFn, Meta, MetaList};
 
-pub(super) fn implement(args: TokenStream, input: TokenStream) -> TokenStream {
-	let args = parse_macro_input!(args as AttributeArgs);
-	let item = parse_macro_input!(input as ItemFn);
+use crate::Result;
 
-	let NestedMeta::Meta(Meta::Path(receiver)) = args
+pub(super) fn implement(item: ItemFn, args: &[Meta]) -> Result<TokenStream> {
+	let Meta::List(MetaList {
+		path,
+		..
+	}) = &args
 		.first()
 		.expect("missing path to trait or item to implement")
 	else {
 		panic!("invalid path to item for implement");
 	};
 
+	let input = item;
 	let out = quote! {
-		impl #receiver {
-			#item
+		impl #path {
+			#input
 		}
 	};
 
-	out.into_token_stream().into()
+	Ok(out.into())
 }

src/macros/mod.rs

@@ -7,23 +7,50 @@ mod rustc;
 mod utils;
 
 use proc_macro::TokenStream;
+use syn::{
+	parse::{Parse, Parser},
+	parse_macro_input, Error, Item, ItemConst, ItemEnum, ItemFn, Meta,
+};
+
+pub(crate) type Result<T> = std::result::Result<T, Error>;
 
 #[proc_macro_attribute]
 pub fn admin_command_dispatch(args: TokenStream, input: TokenStream) -> TokenStream {
-	admin::command_dispatch(args, input)
+	attribute_macro::<ItemEnum, _>(args, input, admin::command_dispatch)
 }
 
 #[proc_macro_attribute]
-pub fn cargo_manifest(args: TokenStream, input: TokenStream) -> TokenStream { cargo::manifest(args, input) }
+pub fn cargo_manifest(args: TokenStream, input: TokenStream) -> TokenStream {
+	attribute_macro::<ItemConst, _>(args, input, cargo::manifest)
+}
 
 #[proc_macro_attribute]
-pub fn recursion_depth(args: TokenStream, input: TokenStream) -> TokenStream { debug::recursion_depth(args, input) }
+pub fn recursion_depth(args: TokenStream, input: TokenStream) -> TokenStream {
+	attribute_macro::<Item, _>(args, input, debug::recursion_depth)
+}
 
 #[proc_macro]
 pub fn rustc_flags_capture(args: TokenStream) -> TokenStream { rustc::flags_capture(args) }
 
 #[proc_macro_attribute]
-pub fn refutable(args: TokenStream, input: TokenStream) -> TokenStream { refutable::refutable(args, input) }
+pub fn refutable(args: TokenStream, input: TokenStream) -> TokenStream {
+	attribute_macro::<ItemFn, _>(args, input, refutable::refutable)
+}
 
 #[proc_macro_attribute]
-pub fn implement(args: TokenStream, input: TokenStream) -> TokenStream { implement::implement(args, input) }
+pub fn implement(args: TokenStream, input: TokenStream) -> TokenStream {
+	attribute_macro::<ItemFn, _>(args, input, implement::implement)
+}
+
+fn attribute_macro<I, F>(args: TokenStream, input: TokenStream, func: F) -> TokenStream
+where
+	F: Fn(I, &[Meta]) -> Result<TokenStream>,
+	I: Parse,
+{
+	let item = parse_macro_input!(input as I);
+	syn::punctuated::Punctuated::<Meta, syn::Token![,]>::parse_terminated
+		.parse(args)
+		.map(|args| args.iter().cloned().collect::<Vec<_>>())
+		.and_then(|ref args| func(item, args))
+		.unwrap_or_else(|e| e.to_compile_error().into())
+}

src/macros/refutable.rs

@@ -1,11 +1,10 @@
 use proc_macro::{Span, TokenStream};
 use quote::{quote, ToTokens};
-use syn::{parse_macro_input, AttributeArgs, FnArg::Typed, Ident, ItemFn, Pat, PatIdent, PatType, Stmt};
+use syn::{FnArg::Typed, Ident, ItemFn, Meta, Pat, PatIdent, PatType, Stmt};
 
-pub(super) fn refutable(args: TokenStream, input: TokenStream) -> TokenStream {
-	let _args = parse_macro_input!(args as AttributeArgs);
-	let mut item = parse_macro_input!(input as ItemFn);
+use crate::Result;
 
+pub(super) fn refutable(mut item: ItemFn, _args: &[Meta]) -> Result<TokenStream> {
 	let inputs = item.sig.inputs.clone();
 	let stmt = &mut item.block.stmts;
 	let sig = &mut item.sig;
@@ -25,16 +24,10 @@ pub(super) fn refutable(args: TokenStream, input: TokenStream) -> TokenStream {
 		let variant = &pat.path;
 		let fields = &pat.fields;
 
-		// new versions of syn can replace this kronecker kludge with get_mut()
-		for (j, input) in sig.inputs.iter_mut().enumerate() {
-			if i != j {
-				continue;
-			}
-
-			let Typed(PatType {
+		let Some(Typed(PatType {
 			ref mut pat,
 			..
-			}) = input
+		})) = sig.inputs.get_mut(i)
 		else {
 			continue;
 		};
@@ -53,9 +46,8 @@ pub(super) fn refutable(args: TokenStream, input: TokenStream) -> TokenStream {
 			let #variant { #( #field ),*, .. } = #name else { panic!("incorrect variant passed to function argument {i}"); };
 		};
 
-			stmt.insert(0, syn::parse2::<Stmt>(refute).expect("syntax error"));
-		}
+		stmt.insert(0, syn::parse2::<Stmt>(refute)?);
 	}
 
-	item.into_token_stream().into()
+	Ok(item.into_token_stream().into())
 }

src/macros/utils.rs

@@ -1,3 +1,18 @@
+use syn::{Expr, Lit, Meta};
+
+pub(crate) fn get_named_string(args: &[Meta], name: &str) -> Option<String> {
+	args.iter().find_map(|arg| {
+		let value = arg.require_name_value().ok()?;
+		let Expr::Lit(ref lit) = value.value else {
+			return None;
+		};
+		let Lit::Str(ref str) = lit.lit else {
+			return None;
+		};
+		value.path.is_ident(name).then_some(str.value())
+	})
+}
+
 #[must_use]
 pub(crate) fn camel_to_snake_string(s: &str) -> String {
 	let mut output = String::with_capacity(