feat: make Parser::*_{delimited} functions on TokenParser return Group

Author: ModProg

CHANGELOG.md

@@ -12,6 +12,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Changed
 - **Breaking Change** Added const generic buffer size to `TokenParser`.
 - **Breaking Change** `Peeker::peek` takes `&[TokenTree]` instead of `TokenParser`.
+- **Breaking Change** `*_{delimiter}` returns `Group` instead of the contained stream.
+  To get to the stream call `.stream()`
 - `TokenParser` peeking supports `n` greater than stack buffer, allowing spilling to heap.
 - Increased default `TokenParser` peek buffer to `6`.
 - Marked parser functions as must_use.

src/assert.rs

@@ -33,7 +33,7 @@ macro_rules! assert_tokens {
     };
     (@G $lhs:ident, $fn:ident, $aggr:expr, $sym:literal, $group:tt, {$($inner:tt)*}, $($rhs:tt)*) => {
         if let Some(lhs) = $lhs.$fn() {
-            let mut lhs = $crate::TokenParser::<_, 3>::from(lhs);
+            let mut lhs = $crate::TokenParser::<_, 3>::from($crate::__private::proc_macro2::Group::stream(&lhs));
             assert_tokens!(@O lhs, concat!($aggr, ' ', $sym), $($inner)*);
         } else if let Some(lhs) = $lhs.next() {
             assert_tokens!(@E $aggr, ($group), lhs);

src/parser.rs

@@ -232,22 +232,20 @@ macro_rules! delimited {
     ($($test:ident, $peek:ident, $peek_n:ident, $name:ident, $doc:literal;)*) => {
         $(#[doc = concat!("Returns the next token if it is a ", $doc ," group.")]
         #[must_use]
-        pub fn $name(&mut self) -> Option<TokenStream> {
-            self.$peek().map(|stream| {
-                self.next().unwrap();
-                stream
+        pub fn $name(&mut self) -> Option<Group> {
+            self.$peek().is_some().then(|| {
+                self.next_group().unwrap()
             })
         })*
         $(#[doc = concat!("Returns the next token if it is a", $doc ," group, without advancing the parser.")]
         #[must_use]
-        pub fn $peek(&mut self) -> Option<TokenStream> {
+        pub fn $peek(&mut self) -> Option<&Group> {
             self.$peek_n(0)
         })*
         $(#[doc = concat!("Returns the `n`th token if it is a ", $doc ," group, without advancing the parser.")]
         #[must_use]
-        pub fn $peek_n(&mut self, n: usize) -> Option<TokenStream> {
-            self.peek_n(n).and_then(|token|
-                token.$test().then(|| token.group().unwrap().stream()))
+        pub fn $peek_n(&mut self, n: usize) -> Option<&Group> {
+            self.peek_n_group(n).filter(|g| g.$test())
         })*
     };
 }