3 files changed, 112 insertions, 29 deletions

diff --git a/crates/hir_def/src/body/lower.rs b/crates/hir_def/src/body/lower.rs
index 63e89a1f4..c11da30d2 100644
--- a/crates/hir_def/src/body/lower.rs
+++ b/crates/hir_def/src/body/lower.rs
@@ -1,10 +1,11 @@
 //! Transforms `ast::Expr` into an equivalent `hir_def::expr::Expr`
 //! representation.
 
-use std::mem;
+use std::{mem, sync::Arc};
 
 use either::Either;
 use hir_expand::{
+    ast_id_map::{AstIdMap, FileAstId},
     hygiene::Hygiene,
     name::{name, AsName, Name},
     ExpandError, HirFileId,
@@ -30,6 +31,7 @@ use crate::{
         LabelId, Literal, LogicOp, MatchArm, Ordering, Pat, PatId, RecordFieldPat, RecordLitField,
         Statement,
     },
+    intern::Interned,
     item_scope::BuiltinShadowMode,
     path::{GenericArgs, Path},
     type_ref::{Mutability, Rawness, TypeRef},
@@ -38,20 +40,39 @@ use crate::{
 
 use super::{diagnostics::BodyDiagnostic, ExprSource, PatSource};
 
-pub(crate) struct LowerCtx {
+pub struct LowerCtx {
     hygiene: Hygiene,
+    file_id: Option<HirFileId>,
+    source_ast_id_map: Option<Arc<AstIdMap>>,
 }
 
 impl LowerCtx {
-    pub(crate) fn new(db: &dyn DefDatabase, file_id: HirFileId) -> Self {
-        LowerCtx { hygiene: Hygiene::new(db.upcast(), file_id) }
+    pub fn new(db: &dyn DefDatabase, file_id: HirFileId) -> Self {
+        LowerCtx {
+            hygiene: Hygiene::new(db.upcast(), file_id),
+            file_id: Some(file_id),
+            source_ast_id_map: Some(db.ast_id_map(file_id)),
+        }
     }
-    pub(crate) fn with_hygiene(hygiene: &Hygiene) -> Self {
-        LowerCtx { hygiene: hygiene.clone() }
+
+    pub fn with_hygiene(hygiene: &Hygiene) -> Self {
+        LowerCtx { hygiene: hygiene.clone(), file_id: None, source_ast_id_map: None }
+    }
+
+    pub(crate) fn hygiene(&self) -> &Hygiene {
+        &self.hygiene
+    }
+
+    pub(crate) fn file_id(&self) -> HirFileId {
+        self.file_id.unwrap()
     }
 
     pub(crate) fn lower_path(&self, ast: ast::Path) -> Option<Path> {
-        Path::from_src(ast, &self.hygiene)
+        Path::from_src(ast, self)
+    }
+
+    pub(crate) fn ast_id<N: AstNode>(&self, item: &N) -> Option<FileAstId<N>> {
+        self.source_ast_id_map.as_ref().map(|ast_id_map| ast_id_map.ast_id(item))
     }
 }
 
@@ -322,8 +343,10 @@ impl ExprCollector<'_> {
                     Vec::new()
                 };
                 let method_name = e.name_ref().map(|nr| nr.as_name()).unwrap_or_else(Name::missing);
-                let generic_args =
-                    e.generic_arg_list().and_then(|it| GenericArgs::from_ast(&self.ctx(), it));
+                let generic_args = e
+                    .generic_arg_list()
+                    .and_then(|it| GenericArgs::from_ast(&self.ctx(), it))
+                    .map(Box::new);
                 self.alloc_expr(
                     Expr::MethodCall { receiver, method_name, args, generic_args },
                     syntax_ptr,
@@ -385,7 +408,7 @@ impl ExprCollector<'_> {
                 self.alloc_expr(Expr::Yield { expr }, syntax_ptr)
             }
             ast::Expr::RecordExpr(e) => {
-                let path = e.path().and_then(|path| self.expander.parse_path(path));
+                let path = e.path().and_then(|path| self.expander.parse_path(path)).map(Box::new);
                 let record_lit = if let Some(nfl) = e.record_expr_field_list() {
                     let fields = nfl
                         .fields()
@@ -430,7 +453,7 @@ impl ExprCollector<'_> {
             }
             ast::Expr::CastExpr(e) => {
                 let expr = self.collect_expr_opt(e.expr());
-                let type_ref = TypeRef::from_ast_opt(&self.ctx(), e.ty());
+                let type_ref = Interned::new(TypeRef::from_ast_opt(&self.ctx(), e.ty()));
                 self.alloc_expr(Expr::Cast { expr, type_ref }, syntax_ptr)
             }
             ast::Expr::RefExpr(e) => {
@@ -464,13 +487,16 @@ impl ExprCollector<'_> {
                 if let Some(pl) = e.param_list() {
                     for param in pl.params() {
                         let pat = self.collect_pat_opt(param.pat());
-                        let type_ref = param.ty().map(|it| TypeRef::from_ast(&self.ctx(), it));
+                        let type_ref =
+                            param.ty().map(|it| Interned::new(TypeRef::from_ast(&self.ctx(), it)));
                         args.push(pat);
                         arg_types.push(type_ref);
                     }
                 }
-                let ret_type =
-                    e.ret_type().and_then(|r| r.ty()).map(|it| TypeRef::from_ast(&self.ctx(), it));
+                let ret_type = e
+                    .ret_type()
+                    .and_then(|r| r.ty())
+                    .map(|it| Interned::new(TypeRef::from_ast(&self.ctx(), it)));
                 let body = self.collect_expr_opt(e.body());
                 self.alloc_expr(Expr::Lambda { args, arg_types, ret_type, body }, syntax_ptr)
             }
@@ -525,8 +551,9 @@ impl ExprCollector<'_> {
                 }
             }
             ast::Expr::MacroCall(e) => {
+                let macro_ptr = AstPtr::new(&e);
                 let mut ids = vec![];
-                self.collect_macro_call(e, syntax_ptr.clone(), true, |this, expansion| {
+                self.collect_macro_call(e, macro_ptr, true, |this, expansion| {
                     ids.push(match expansion {
                         Some(it) => this.collect_expr(it),
                         None => this.alloc_expr(Expr::Missing, syntax_ptr.clone()),
@@ -549,7 +576,7 @@ impl ExprCollector<'_> {
     fn collect_macro_call<F: FnMut(&mut Self, Option<T>), T: ast::AstNode>(
         &mut self,
         e: ast::MacroCall,
-        syntax_ptr: AstPtr<ast::Expr>,
+        syntax_ptr: AstPtr<ast::MacroCall>,
         is_error_recoverable: bool,
         mut collector: F,
     ) {
@@ -561,9 +588,13 @@ impl ExprCollector<'_> {
 
         let res = match res {
             Ok(res) => res,
-            Err(UnresolvedMacro) => {
+            Err(UnresolvedMacro { path }) => {
                 self.source_map.diagnostics.push(BodyDiagnostic::UnresolvedMacroCall(
-                    UnresolvedMacroCall { file: outer_file, node: syntax_ptr.cast().unwrap() },
+                    UnresolvedMacroCall {
+                        file: outer_file,
+                        node: syntax_ptr.cast().unwrap(),
+                        path,
+                    },
                 ));
                 collector(self, None);
                 return;
@@ -625,7 +656,8 @@ impl ExprCollector<'_> {
                     return;
                 }
                 let pat = self.collect_pat_opt(stmt.pat());
-                let type_ref = stmt.ty().map(|it| TypeRef::from_ast(&self.ctx(), it));
+                let type_ref =
+                    stmt.ty().map(|it| Interned::new(TypeRef::from_ast(&self.ctx(), it)));
                 let initializer = stmt.initializer().map(|e| self.collect_expr(e));
                 self.statements_in_scope.push(Statement::Let { pat, type_ref, initializer });
             }
@@ -636,10 +668,14 @@ impl ExprCollector<'_> {
 
                 // Note that macro could be expended to multiple statements
                 if let Some(ast::Expr::MacroCall(m)) = stmt.expr() {
+                    let macro_ptr = AstPtr::new(&m);
                     let syntax_ptr = AstPtr::new(&stmt.expr().unwrap());
 
-                    self.collect_macro_call(m, syntax_ptr.clone(), false, |this, expansion| {
-                        match expansion {
+                    self.collect_macro_call(
+                        m,
+                        macro_ptr,
+                        false,
+                        |this, expansion| match expansion {
                             Some(expansion) => {
                                 let statements: ast::MacroStmts = expansion;
 
@@ -653,8 +689,8 @@ impl ExprCollector<'_> {
                                 let expr = this.alloc_expr(Expr::Missing, syntax_ptr.clone());
                                 this.statements_in_scope.push(Statement::Expr(expr));
                             }
-                        }
-                    });
+                        },
+                    );
                 } else {
                     let expr = self.collect_expr_opt(stmt.expr());
                     self.statements_in_scope.push(Statement::Expr(expr));
@@ -755,7 +791,7 @@ impl ExprCollector<'_> {
                 }
             }
             ast::Pat::TupleStructPat(p) => {
-                let path = p.path().and_then(|path| self.expander.parse_path(path));
+                let path = p.path().and_then(|path| self.expander.parse_path(path)).map(Box::new);
                 let (args, ellipsis) = self.collect_tuple_pat(p.fields());
                 Pat::TupleStruct { path, args, ellipsis }
             }
@@ -765,7 +801,7 @@ impl ExprCollector<'_> {
                 Pat::Ref { pat, mutability }
             }
             ast::Pat::PathPat(p) => {
-                let path = p.path().and_then(|path| self.expander.parse_path(path));
+                let path = p.path().and_then(|path| self.expander.parse_path(path)).map(Box::new);
                 path.map(Pat::Path).unwrap_or(Pat::Missing)
             }
             ast::Pat::OrPat(p) => {
@@ -779,7 +815,7 @@ impl ExprCollector<'_> {
             }
             ast::Pat::WildcardPat(_) => Pat::Wild,
             ast::Pat::RecordPat(p) => {
-                let path = p.path().and_then(|path| self.expander.parse_path(path));
+                let path = p.path().and_then(|path| self.expander.parse_path(path)).map(Box::new);
                 let args: Vec<_> = p
                     .record_pat_field_list()
                     .expect("every struct should have a field list")
@@ -841,8 +877,23 @@ impl ExprCollector<'_> {
                     Pat::Missing
                 }
             }
+            ast::Pat::MacroPat(mac) => match mac.macro_call() {
+                Some(call) => {
+                    let macro_ptr = AstPtr::new(&call);
+                    let mut pat = None;
+                    self.collect_macro_call(call, macro_ptr, true, |this, expanded_pat| {
+                        pat = Some(this.collect_pat_opt(expanded_pat));
+                    });
+
+                    match pat {
+                        Some(pat) => return pat,
+                        None => Pat::Missing,
+                    }
+                }
+                None => Pat::Missing,
+            },
             // FIXME: implement
-            ast::Pat::RangePat(_) | ast::Pat::MacroPat(_) => Pat::Missing,
+            ast::Pat::RangePat(_) => Pat::Missing,
         };
         let ptr = AstPtr::new(&pat);
         self.alloc_pat(pattern, Either::Left(ptr))
diff --git a/crates/hir_def/src/body/tests.rs b/crates/hir_def/src/body/tests.rs
index faa133297..3e8f16306 100644
--- a/crates/hir_def/src/body/tests.rs
+++ b/crates/hir_def/src/body/tests.rs
@@ -40,6 +40,14 @@ fn block_def_map_at(ra_fixture: &str) -> String {
     module.def_map(&db).dump(&db)
 }
 
+fn check_block_scopes_at(ra_fixture: &str, expect: Expect) {
+    let (db, position) = crate::test_db::TestDB::with_position(ra_fixture);
+
+    let module = db.module_at_position(position);
+    let actual = module.def_map(&db).dump_block_scopes(&db);
+    expect.assert_eq(&actual);
+}
+
 fn check_at(ra_fixture: &str, expect: Expect) {
     let actual = block_def_map_at(ra_fixture);
     expect.assert_eq(&actual);
@@ -143,7 +151,7 @@ fn f() {
   //^^^^^^^^^^^^^ could not convert tokens
 
     env!("OUT_DIR");
-  //^^^^^^^^^^^^^^^ `OUT_DIR` not set, enable "load out dirs from check" to fix
+  //^^^^^^^^^^^^^^^ `OUT_DIR` not set, enable "run build scripts" to fix
 
     compile_error!("compile_error works");
   //^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ compile_error works
@@ -180,7 +188,7 @@ fn unresolved_macro_diag() {
         r#"
 fn f() {
     m!();
-  //^^^^ unresolved macro call
+  //^^^^ unresolved macro `m!`
 }
       "#,
     );
diff --git a/crates/hir_def/src/body/tests/block.rs b/crates/hir_def/src/body/tests/block.rs
index 3b6ba4cde..bc3d0f138 100644
--- a/crates/hir_def/src/body/tests/block.rs
+++ b/crates/hir_def/src/body/tests/block.rs
@@ -134,6 +134,30 @@ struct Struct {}
 }
 
 #[test]
+fn nested_module_scoping() {
+    check_block_scopes_at(
+        r#"
+fn f() {
+    mod module {
+        struct Struct {}
+        fn f() {
+            use self::Struct;
+            $0
+        }
+    }
+}
+    "#,
+        expect![[r#"
+            BlockId(1) in ModuleId { krate: CrateId(0), block: Some(BlockId(0)), local_id: Idx::<ModuleData>(0) }
+            BlockId(0) in ModuleId { krate: CrateId(0), block: None, local_id: Idx::<ModuleData>(0) }
+            crate scope
+        "#]],
+    );
+    // FIXME: The module nesting here is wrong!
+    // The first block map should be located in module #1 (`mod module`), not #0 (BlockId(0) root module)
+}
+
+#[test]
 fn legacy_macro_items() {
     // Checks that legacy-scoped `macro_rules!` from parent namespaces are resolved and expanded
     // correctly.