From cc04cfc982b0321b55d54937709c01ca242eb5ff Mon Sep 17 00:00:00 2001
From: Lukas Wirth <lukastw97@gmail.com>
Date: Sun, 30 Jan 2022 22:18:32 +0100
Subject: Reduce allocations in attribute collection

---
 crates/syntax/src/ast.rs          |  4 ++--
 crates/syntax/src/ast/node_ext.rs | 11 +++--------
 crates/syntax/src/ast/traits.rs   | 20 +++++++++++++-------
 3 files changed, 18 insertions(+), 17 deletions(-)

(limited to 'crates/syntax/src')

diff --git a/crates/syntax/src/ast.rs b/crates/syntax/src/ast.rs
index 5c1aed3cd48..91b46cf8e9d 100644
--- a/crates/syntax/src/ast.rs
+++ b/crates/syntax/src/ast.rs
@@ -27,8 +27,8 @@ pub use self::{
     operators::{ArithOp, BinaryOp, CmpOp, LogicOp, Ordering, RangeOp, UnaryOp},
     token_ext::{CommentKind, CommentPlacement, CommentShape, IsString, QuoteOffsets, Radix},
     traits::{
-        DocCommentIter, HasArgList, HasAttrs, HasDocComments, HasGenericParams, HasLoopBody,
-        HasModuleItem, HasName, HasTypeBounds, HasVisibility,
+        AttrDocCommentIter, DocCommentIter, HasArgList, HasAttrs, HasDocComments, HasGenericParams,
+        HasLoopBody, HasModuleItem, HasName, HasTypeBounds, HasVisibility,
     },
 };
 
diff --git a/crates/syntax/src/ast/node_ext.rs b/crates/syntax/src/ast/node_ext.rs
index 705aa5edac4..7211c77e880 100644
--- a/crates/syntax/src/ast/node_ext.rs
+++ b/crates/syntax/src/ast/node_ext.rs
@@ -160,14 +160,9 @@ impl ast::Attr {
     }
 
     pub fn kind(&self) -> AttrKind {
-        let first_token = self.syntax().first_token();
-        let first_token_kind = first_token.as_ref().map(SyntaxToken::kind);
-        let second_token_kind =
-            first_token.and_then(|token| token.next_token()).as_ref().map(SyntaxToken::kind);
-
-        match (first_token_kind, second_token_kind) {
-            (Some(T![#]), Some(T![!])) => AttrKind::Inner,
-            _ => AttrKind::Outer,
+        match self.excl_token() {
+            Some(_) => AttrKind::Inner,
+            None => AttrKind::Outer,
         }
     }
 
diff --git a/crates/syntax/src/ast/traits.rs b/crates/syntax/src/ast/traits.rs
index 98b1087e641..aa2b7ed5c8b 100644
--- a/crates/syntax/src/ast/traits.rs
+++ b/crates/syntax/src/ast/traits.rs
@@ -76,8 +76,8 @@ pub trait HasDocComments: HasAttrs {
     fn doc_comments(&self) -> DocCommentIter {
         DocCommentIter { iter: self.syntax().children_with_tokens() }
     }
-    fn doc_comments_and_attrs(&self) -> AttrCommentIter {
-        AttrCommentIter { iter: self.syntax().children_with_tokens() }
+    fn doc_comments_and_attrs(&self) -> AttrDocCommentIter {
+        AttrDocCommentIter { iter: self.syntax().children_with_tokens() }
     }
 }
 
@@ -113,17 +113,23 @@ impl Iterator for DocCommentIter {
     }
 }
 
-pub struct AttrCommentIter {
+pub struct AttrDocCommentIter {
     iter: SyntaxElementChildren,
 }
 
-impl Iterator for AttrCommentIter {
-    type Item = Either<ast::Comment, ast::Attr>;
+impl AttrDocCommentIter {
+    pub fn from_syntax_node(syntax_node: &ast::SyntaxNode) -> AttrDocCommentIter {
+        AttrDocCommentIter { iter: syntax_node.children_with_tokens() }
+    }
+}
+
+impl Iterator for AttrDocCommentIter {
+    type Item = Either<ast::Attr, ast::Comment>;
     fn next(&mut self) -> Option<Self::Item> {
         self.iter.by_ref().find_map(|el| match el {
-            SyntaxElement::Node(node) => ast::Attr::cast(node).map(Either::Right),
+            SyntaxElement::Node(node) => ast::Attr::cast(node).map(Either::Left),
             SyntaxElement::Token(tok) => {
-                ast::Comment::cast(tok).filter(ast::Comment::is_doc).map(Either::Left)
+                ast::Comment::cast(tok).filter(ast::Comment::is_doc).map(Either::Right)
             }
         })
     }
-- 
cgit 1.4.1-3-g733a5