Auto merge of rust-lang#17195 - Veykril:unsafe-attr, r=Veykril

Implement unsafe attribute parsing

Author: bors

src/tools/rust-analyzer/crates/hir-expand/src/attrs.rs

@@ -252,8 +252,18 @@ impl Attr {
         Some(Attr { id, path, input, ctxt: span.ctx })
     }
 
-    fn from_tt(db: &dyn ExpandDatabase, tt: &[tt::TokenTree], id: AttrId) -> Option<Attr> {
-        let ctxt = tt.first()?.first_span().ctx;
+    fn from_tt(db: &dyn ExpandDatabase, mut tt: &[tt::TokenTree], id: AttrId) -> Option<Attr> {
+        if matches!(tt,
+            [tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident { text, .. })), ..]
+            if text == "unsafe"
+        ) {
+            match tt.get(1) {
+                Some(tt::TokenTree::Subtree(subtree)) => tt = &subtree.token_trees,
+                _ => return None,
+            }
+        }
+        let first = &tt.first()?;
+        let ctxt = first.first_span().ctx;
         let path_end = tt
             .iter()
             .position(|tt| {
@@ -435,7 +445,7 @@ fn inner_attributes(
 
 // Input subtree is: `(cfg, $(attr),+)`
 // Split it up into a `cfg` subtree and the `attr` subtrees.
-pub fn parse_cfg_attr_input(
+fn parse_cfg_attr_input(
     subtree: &Subtree,
 ) -> Option<(&[tt::TokenTree], impl Iterator<Item = &[tt::TokenTree]>)> {
     let mut parts = subtree

src/tools/rust-analyzer/crates/ide/src/runnables.rs

@@ -609,6 +609,9 @@ fn main() {}
 #[export_name = "main"]
 fn __cortex_m_rt_main_trampoline() {}
 
+#[unsafe(export_name = "main")]
+fn __cortex_m_rt_main_trampoline_unsafe() {}
+
 #[test]
 fn test_foo() {}
 
@@ -628,13 +631,14 @@ mod not_a_root {
 "#,
             expect![[r#"
                 [
-                    "(TestMod, NavigationTarget { file_id: FileId(0), full_range: 0..253, name: \"\", kind: Module })",
+                    "(TestMod, NavigationTarget { file_id: FileId(0), full_range: 0..331, name: \"\", kind: Module })",
                     "(Bin, NavigationTarget { file_id: FileId(0), full_range: 1..13, focus_range: 4..8, name: \"main\", kind: Function })",
                     "(Bin, NavigationTarget { file_id: FileId(0), full_range: 15..76, focus_range: 42..71, name: \"__cortex_m_rt_main_trampoline\", kind: Function })",
-                    "(Test, NavigationTarget { file_id: FileId(0), full_range: 78..102, focus_range: 89..97, name: \"test_foo\", kind: Function })",
-                    "(Test, NavigationTarget { file_id: FileId(0), full_range: 104..155, focus_range: 136..150, name: \"test_full_path\", kind: Function })",
-                    "(Test, NavigationTarget { file_id: FileId(0), full_range: 157..191, focus_range: 178..186, name: \"test_foo\", kind: Function })",
-                    "(Bench, NavigationTarget { file_id: FileId(0), full_range: 193..215, focus_range: 205..210, name: \"bench\", kind: Function })",
+                    "(Bin, NavigationTarget { file_id: FileId(0), full_range: 78..154, focus_range: 113..149, name: \"__cortex_m_rt_main_trampoline_unsafe\", kind: Function })",
+                    "(Test, NavigationTarget { file_id: FileId(0), full_range: 156..180, focus_range: 167..175, name: \"test_foo\", kind: Function })",
+                    "(Test, NavigationTarget { file_id: FileId(0), full_range: 182..233, focus_range: 214..228, name: \"test_full_path\", kind: Function })",
+                    "(Test, NavigationTarget { file_id: FileId(0), full_range: 235..269, focus_range: 256..264, name: \"test_foo\", kind: Function })",
+                    "(Bench, NavigationTarget { file_id: FileId(0), full_range: 271..293, focus_range: 283..288, name: \"bench\", kind: Function })",
                 ]
             "#]],
         );

src/tools/rust-analyzer/crates/parser/src/grammar/attributes.rs

@@ -36,8 +36,33 @@ fn attr(p: &mut Parser<'_>, inner: bool) {
     attr.complete(p, ATTR);
 }
 
+// test metas
+// #![simple_ident]
+// #![simple::path]
+// #![simple_ident_expr = ""]
+// #![simple::path::Expr = ""]
+// #![simple_ident_tt(a b c)]
+// #![simple_ident_tt[a b c]]
+// #![simple_ident_tt{a b c}]
+// #![simple::path::tt(a b c)]
+// #![simple::path::tt[a b c]]
+// #![simple::path::tt{a b c}]
+// #![unsafe(simple_ident)]
+// #![unsafe(simple::path)]
+// #![unsafe(simple_ident_expr = "")]
+// #![unsafe(simple::path::Expr = "")]
+// #![unsafe(simple_ident_tt(a b c))]
+// #![unsafe(simple_ident_tt[a b c])]
+// #![unsafe(simple_ident_tt{a b c})]
+// #![unsafe(simple::path::tt(a b c))]
+// #![unsafe(simple::path::tt[a b c])]
+// #![unsafe(simple::path::tt{a b c})]
 pub(super) fn meta(p: &mut Parser<'_>) {
     let meta = p.start();
+    let is_unsafe = p.eat(T![unsafe]);
+    if is_unsafe {
+        p.expect(T!['(']);
+    }
     paths::use_path(p);
 
     match p.current() {
@@ -50,6 +75,9 @@ pub(super) fn meta(p: &mut Parser<'_>) {
         T!['('] | T!['['] | T!['{'] => items::token_tree(p),
         _ => {}
     }
+    if is_unsafe {
+        p.expect(T![')']);
+    }
 
     meta.complete(p, META);
 }