Record macro def site spans

Author: Veykril

crates/hir-def/src/db.rs

@@ -326,7 +326,7 @@ fn macro_def(db: &dyn DefDatabase, id: MacroId) -> MacroDefId {
 
     match id {
         MacroId::Macro2Id(it) => {
-            let loc = it.lookup(db);
+            let loc: Macro2Loc = it.lookup(db);
 
             let item_tree = loc.id.item_tree(db);
             let makro = &item_tree[loc.id.value];
@@ -335,10 +335,13 @@ fn macro_def(db: &dyn DefDatabase, id: MacroId) -> MacroDefId {
                 kind: kind(loc.expander, loc.id.file_id(), makro.ast_id.upcast()),
                 local_inner: false,
                 allow_internal_unsafe: loc.allow_internal_unsafe,
+                def_site: db
+                    .span_map(loc.id.file_id())
+                    .span_for_range(db.ast_id_map(loc.id.file_id()).get(makro.ast_id).text_range()),
             }
         }
         MacroId::MacroRulesId(it) => {
-            let loc = it.lookup(db);
+            let loc: MacroRulesLoc = it.lookup(db);
 
             let item_tree = loc.id.item_tree(db);
             let makro = &item_tree[loc.id.value];
@@ -347,6 +350,9 @@ fn macro_def(db: &dyn DefDatabase, id: MacroId) -> MacroDefId {
                 kind: kind(loc.expander, loc.id.file_id(), makro.ast_id.upcast()),
                 local_inner: loc.local_inner,
                 allow_internal_unsafe: loc.allow_internal_unsafe,
+                def_site: db
+                    .span_map(loc.id.file_id())
+                    .span_for_range(db.ast_id_map(loc.id.file_id()).get(makro.ast_id).text_range()),
             }
         }
         MacroId::ProcMacroId(it) => {
@@ -363,6 +369,9 @@ fn macro_def(db: &dyn DefDatabase, id: MacroId) -> MacroDefId {
                 ),
                 local_inner: false,
                 allow_internal_unsafe: false,
+                def_site: db
+                    .span_map(loc.id.file_id())
+                    .span_for_range(db.ast_id_map(loc.id.file_id()).get(makro.ast_id).text_range()),
             }
         }
     }

crates/hir-expand/src/lib.rs

@@ -179,7 +179,7 @@ pub struct MacroDefId {
     pub kind: MacroDefKind,
     pub local_inner: bool,
     pub allow_internal_unsafe: bool,
-    // pub def_site: Span,
+    pub def_site: Span,
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]

crates/hir-expand/src/span_map.rs

@@ -38,6 +38,10 @@ impl mbe::SpanMapper<Span> for SpanMapRef<'_> {
 impl SpanMap {
     pub fn span_for_range(&self, range: TextRange) -> Span {
         match self {
+            // FIXME: Is it correct for us to only take the span at the start? This feels somewhat
+            // wrong. The context will be right, but the range could be considered wrong. See
+            // https://github.com/rust-lang/rust/issues/23480, we probably want to fetch the span at
+            // the start and end, then merge them like rustc does in `Span::to
             Self::ExpansionSpanMap(span_map) => span_map.span_at(range.start()),
             Self::RealSpanMap(span_map) => span_map.span_for_range(range),
         }