Merge pull request #84 from alex/bump-syn

Switch to syn 2.0

.github/workflows/default.yml

@@ -14,15 +14,15 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        RUST: ["1.48", stable, beta, nightly]
+        RUST: ["1.56", stable, beta, nightly]
     steps:
       - uses: actions/checkout@v2
       - name: Set Rust version
         run: rustup default ${{ matrix.RUST }}
       - name: Build
-        run: cargo build --verbose ${{ matrix.RUST != '1.48' && '--features=__tokio' || '' }}
+        run: cargo build --verbose
       - name: Run tests
-        run: cargo test --verbose ${{ matrix.RUST != '1.48' && '--features=__tokio' || '' }}
+        run: cargo test --verbose
 
   no-std-test:
     runs-on: ubuntu-latest

examples/Cargo.toml

@@ -14,11 +14,10 @@ rustdoc-args = ["--document-private-items"]
 [lib]
 
 [features]
-default = []
+default = ["std"]
 # Disables any tests that are not compatible or not intended to run under Miri
 miri = []
 std = []
-__tokio = ["tokio", "std"]
 
 [dependencies]
 ouroboros = { version = "0.17.0", path = "../ouroboros" }
@@ -27,3 +26,4 @@ tokio = { version = "1.27.0", features = [ "macros", "rt" ], optional = true }
 [dev-dependencies]
 rustversion = "1.0.11"
 trybuild = "=1.0.50"
+tokio = { version = "1.25.0", features = [ "macros", "rt" ] }

examples/src/ok_tests.rs

@@ -90,7 +90,7 @@ fn box_and_ref() {
 
 // Miri crashes with Pin<Box<Future>> types due to
 // https://github.com/rust-lang/miri/issues/1038
-#[cfg(all(not(feature = "miri"), feature = "tokio"))]
+#[cfg(all(not(feature = "miri"), feature = "std"))]
 #[tokio::test]
 async fn async_new() {
     use std::future::Future;
@@ -106,7 +106,7 @@ async fn async_new() {
 
 // Miri crashes with Pin<Box<Future>> types due to
 // https://github.com/rust-lang/miri/issues/1038
-#[cfg(all(not(feature = "miri"), feature = "tokio"))]
+#[cfg(all(not(feature = "miri"), feature = "std"))]
 #[tokio::test]
 async fn async_try_new() {
     let bar = BoxAndRefAsyncTryBuilder {
@@ -122,7 +122,7 @@ async fn async_try_new() {
 
 // Miri crashes with Pin<Box<Future>> types due to
 // https://github.com/rust-lang/miri/issues/1038
-#[cfg(all(not(feature = "miri"), feature = "tokio"))]
+#[cfg(all(not(feature = "miri"), feature = "std"))]
 #[tokio::test]
 async fn async_try_new_err() {
     let result = BoxAndRefAsyncTryBuilder {

ouroboros_macro/Cargo.toml

@@ -16,7 +16,7 @@ heck = "0.4.1"
 proc-macro2 = "1.0"
 proc-macro-error = "1.0.4"
 quote = "1.0"
-syn = { version = "1.0", features = ["full"] }
+syn = { version = "2.0", features = ["full"] }
 
 [features]
 std = []

ouroboros_macro/src/info_structures.rs

@@ -3,7 +3,7 @@ use proc_macro2::{Ident, TokenStream};
 use quote::{format_ident, quote, ToTokens};
 use syn::{
     punctuated::Punctuated, token::Comma, Attribute, ConstParam, Error, GenericParam, Generics,
-    LifetimeDef, Type, TypeParam, Visibility,
+    LifetimeParam, Type, TypeParam, Visibility,
 };
 
 #[derive(Clone, Copy)]
@@ -123,7 +123,7 @@ impl StructInfo {
             Type(TypeParam { ident, .. }) | Const(ConstParam { ident, .. }) => {
                 ident.to_token_stream()
             }
-            Lifetime(LifetimeDef { lifetime, .. }) => lifetime.to_token_stream(),
+            Lifetime(LifetimeParam { lifetime, .. }) => lifetime.to_token_stream(),
         });
         quote! { <'_, '_, #(#params,)*> }
     }

ouroboros_macro/src/lib.rs

@@ -53,8 +53,11 @@ fn self_referencing_impl(
         create_try_builder_and_constructor(&info, options, BuilderType::Sync)?;
     let (async_try_builder_struct_name, async_try_builder_def, async_try_constructor_def) =
         create_try_builder_and_constructor(&info, options, BuilderType::Async)?;
-    let (async_send_try_builder_struct_name, async_send_try_builder_def, async_send_try_constructor_def) =
-        create_try_builder_and_constructor(&info, options, BuilderType::AsyncSend)?;
+    let (
+        async_send_try_builder_struct_name,
+        async_send_try_builder_def,
+        async_send_try_constructor_def,
+    ) = create_try_builder_and_constructor(&info, options, BuilderType::AsyncSend)?;
 
     let with_defs = make_with_functions(&info, options)?;
     let (with_all_struct_defs, with_all_fn_defs) = make_with_all_function(&info, options)?;

ouroboros_macro/src/parse.rs

@@ -1,6 +1,6 @@
 use proc_macro2::{Delimiter, Span, TokenTree};
 use quote::format_ident;
-use syn::{spanned::Spanned, Attribute, Error, Fields, GenericParam, ItemStruct};
+use syn::{spanned::Spanned, Attribute, Error, Fields, GenericParam, ItemStruct, Meta};
 
 use crate::{
     covariance_detection::type_is_covariant_over_this_lifetime,
@@ -15,12 +15,14 @@ fn handle_borrows_attr(
 ) -> Result<(), Error> {
     let mut borrow_mut = false;
     let mut waiting_for_comma = false;
-    let tokens = attr.tokens.clone();
-    let possible_error = Error::new_spanned(&tokens, "Invalid syntax for borrows() macro.");
-    let tokens = if let Some(TokenTree::Group(group)) = tokens.into_iter().next() {
-        group.stream()
-    } else {
-        return Err(possible_error);
+    let tokens = match &attr.meta {
+        Meta::List(ml) => ml.tokens.clone(),
+        _ => {
+            return Err(Error::new_spanned(
+                &attr.meta,
+                "Invalid syntax for borrows() macro.",
+            ))
+        }
     };
     for token in tokens {
         if let TokenTree::Ident(ident) = token {
@@ -113,7 +115,10 @@ fn parse_derive_token(token: &TokenTree) -> Result<Option<Derive>, Error> {
 }
 
 fn parse_derive_attribute(attr: &Attribute) -> Result<Vec<Derive>, Error> {
-    let body = &attr.tokens;
+    let body = match &attr.meta {
+        Meta::List(ml) => &ml.tokens,
+        _ => unreachable!(),
+    };
     if let Some(TokenTree::Group(body)) = body.clone().into_iter().next() {
         if body.delimiter() != Delimiter::Parenthesis {
             panic!("TODO: nice error, bad define syntax")
@@ -156,7 +161,7 @@ pub fn parse_struct(def: &ItemStruct) -> Result<StructInfo, Error> {
                 let mut covariant = type_is_covariant_over_this_lifetime(&field.ty);
                 let mut remove_attrs = Vec::new();
                 for (index, attr) in field.attrs.iter().enumerate() {
-                    let path = &attr.path;
+                    let path = &attr.path();
                     if path.leading_colon.is_some() {
                         continue;
                     }
@@ -246,7 +251,7 @@ pub fn parse_struct(def: &ItemStruct) -> Result<StructInfo, Error> {
     let mut attributes = Vec::new();
     let mut derives = Vec::new();
     for attr in &def.attrs {
-        let p = &attr.path.segments;
+        let p = &attr.path().segments;
         if p.len() == 0 {
             return Err(Error::new(p.span(), &format!("Unsupported attribute")));
         }