5 files changed, 34 insertions, 48 deletions

diff --git a/crates/hir_def/src/attr.rs b/crates/hir_def/src/attr.rs
index 97cdbbb9e..7b41b148c 100644
--- a/crates/hir_def/src/attr.rs
+++ b/crates/hir_def/src/attr.rs
@@ -9,6 +9,7 @@ use hir_expand::{hygiene::Hygiene, name::AsName, AstId, InFile};
 use itertools::Itertools;
 use la_arena::ArenaMap;
 use mbe::ast_to_token_tree;
+use smallvec::{smallvec, SmallVec};
 use syntax::{
     ast::{self, AstNode, AttrsOwner},
     match_ast, AstToken, SmolStr, SyntaxNode,
@@ -134,53 +135,42 @@ impl RawAttrs {
         let crate_graph = db.crate_graph();
         let new_attrs = self
             .iter()
-            .filter_map(|attr| {
+            .flat_map(|attr| -> SmallVec<[_; 1]> {
                 let attr = attr.clone();
                 let is_cfg_attr =
                     attr.path.as_ident().map_or(false, |name| *name == hir_expand::name![cfg_attr]);
                 if !is_cfg_attr {
-                    return Some(attr);
+                    return smallvec![attr];
                 }
 
                 let subtree = match &attr.input {
                     Some(AttrInput::TokenTree(it)) => it,
-                    _ => return Some(attr),
+                    _ => return smallvec![attr],
                 };
 
-                // Input subtree is: `(cfg, attr)`
-                // Split it up into a `cfg` and an `attr` subtree.
+                // Input subtree is: `(cfg, $(attr),+)`
+                // Split it up into a `cfg` subtree and the `attr` subtrees.
                 // FIXME: There should be a common API for this.
-                let mut saw_comma = false;
-                let (mut cfg, attr): (Vec<_>, Vec<_>) =
-                    subtree.clone().token_trees.into_iter().partition(|tree| {
-                        if saw_comma {
-                            return false;
-                        }
-
-                        match tree {
-                            tt::TokenTree::Leaf(tt::Leaf::Punct(p)) if p.char == ',' => {
-                                saw_comma = true;
-                            }
-                            _ => {}
-                        }
-
-                        true
-                    });
-                cfg.pop(); // `,` ends up in here
-
-                let attr = Subtree { delimiter: None, token_trees: attr };
-                let cfg = Subtree { delimiter: subtree.delimiter, token_trees: cfg };
+                let mut parts = subtree.token_trees.split(
+                    |tt| matches!(tt, tt::TokenTree::Leaf(tt::Leaf::Punct(p)) if p.char == ','),
+                );
+                let cfg = parts.next().unwrap();
+                let cfg = Subtree { delimiter: subtree.delimiter, token_trees: cfg.to_vec() };
                 let cfg = CfgExpr::parse(&cfg);
+                let attrs = parts.filter(|a| !a.is_empty()).filter_map(|attr| {
+                    let tree = Subtree { delimiter: None, token_trees: attr.to_vec() };
+                    let attr = ast::Attr::parse(&format!("#[{}]", tree)).ok()?;
+                    let hygiene = Hygiene::new_unhygienic(); // FIXME
+                    Attr::from_src(attr, &hygiene)
+                });
 
                 let cfg_options = &crate_graph[krate].cfg_options;
                 if cfg_options.check(&cfg) == Some(false) {
-                    None
+                    smallvec![]
                 } else {
                     cov_mark::hit!(cfg_attr_active);
 
-                    let attr = ast::Attr::parse(&format!("#[{}]", attr)).ok()?;
-                    let hygiene = Hygiene::new_unhygienic(); // FIXME
-                    Attr::from_src(attr, &hygiene)
+                    attrs.collect()
                 }
             })
             .collect();
diff --git a/crates/hir_def/src/item_tree.rs b/crates/hir_def/src/item_tree.rs
index 6bb334573..09bcb10dc 100644
--- a/crates/hir_def/src/item_tree.rs
+++ b/crates/hir_def/src/item_tree.rs
@@ -209,18 +209,6 @@ impl ItemTree {
         }
     }
 
-    pub fn source<S: ItemTreeNode>(&self, db: &dyn DefDatabase, of: ItemTreeId<S>) -> S::Source {
-        // This unwrap cannot fail, since it has either succeeded above, or resulted in an empty
-        // ItemTree (in which case there is no valid `FileItemTreeId` to call this method with).
-        let root =
-            db.parse_or_expand(of.file_id).expect("parse_or_expand failed on constructed ItemTree");
-
-        let id = self[of.value].ast_id();
-        let map = db.ast_id_map(of.file_id);
-        let ptr = map.get(id);
-        ptr.to_node(&root)
-    }
-
     fn data(&self) -> &ItemTreeData {
         self.data.as_ref().expect("attempted to access data of empty ItemTree")
     }
diff --git a/crates/hir_def/src/lib.rs b/crates/hir_def/src/lib.rs
index 6d11c5be4..c6655c5fb 100644
--- a/crates/hir_def/src/lib.rs
+++ b/crates/hir_def/src/lib.rs
@@ -341,6 +341,16 @@ pub enum DefWithBodyId {
 
 impl_from!(FunctionId, ConstId, StaticId for DefWithBodyId);
 
+impl DefWithBodyId {
+    pub fn as_generic_def_id(self) -> Option<GenericDefId> {
+        match self {
+            DefWithBodyId::FunctionId(f) => Some(f.into()),
+            DefWithBodyId::StaticId(_) => None,
+            DefWithBodyId::ConstId(c) => Some(c.into()),
+        }
+    }
+}
+
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
 pub enum AssocItemId {
     FunctionId(FunctionId),
diff --git a/crates/hir_def/src/nameres/tests/diagnostics.rs b/crates/hir_def/src/nameres/tests/diagnostics.rs
index d5ef8ceb5..1b8e885b0 100644
--- a/crates/hir_def/src/nameres/tests/diagnostics.rs
+++ b/crates/hir_def/src/nameres/tests/diagnostics.rs
@@ -149,6 +149,9 @@ fn inactive_via_cfg_attr() {
           #[cfg_attr(not(never), cfg(not(no)))] fn f() {}
 
           #[cfg_attr(never, cfg(no))] fn g() {}
+
+          #[cfg_attr(not(never), inline, cfg(no))] fn h() {}
+        //^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ code is inactive due to #[cfg] directives: no is disabled
         "#,
     );
 }
diff --git a/crates/hir_def/src/test_db.rs b/crates/hir_def/src/test_db.rs
index eda982c85..10977761c 100644
--- a/crates/hir_def/src/test_db.rs
+++ b/crates/hir_def/src/test_db.rs
@@ -15,7 +15,7 @@ use rustc_hash::FxHashSet;
 use syntax::{algo, ast, AstNode, TextRange, TextSize};
 use test_utils::extract_annotations;
 
-use crate::{db::DefDatabase, nameres::DefMap, Lookup, ModuleDefId, ModuleId};
+use crate::{db::DefDatabase, nameres::DefMap, src::HasSource, Lookup, ModuleDefId, ModuleId};
 
 #[salsa::database(
     base_db::SourceDatabaseExtStorage,
@@ -115,14 +115,9 @@ impl TestDB {
             if file_id != position.file_id.into() {
                 continue;
             }
-            let root = self.parse_or_expand(file_id).unwrap();
-            let ast_map = self.ast_id_map(file_id);
-            let item_tree = self.item_tree(file_id);
             for decl in module.scope.declarations() {
                 if let ModuleDefId::FunctionId(it) = decl {
-                    let ast =
-                        ast_map.get(item_tree[it.lookup(self).id.value].ast_id).to_node(&root);
-                    let range = ast.syntax().text_range();
+                    let range = it.lookup(self).source(self).value.syntax().text_range();
 
                     if !range.contains(position.offset) {
                         continue;