5 files changed, 294 insertions, 126 deletions

diff --git a/crates/hir_def/src/nameres/collector.rs b/crates/hir_def/src/nameres/collector.rs
index 0cd61698c..e51d89b43 100644
--- a/crates/hir_def/src/nameres/collector.rs
+++ b/crates/hir_def/src/nameres/collector.rs
@@ -13,7 +13,7 @@ use hir_expand::{
     builtin_macro::find_builtin_macro,
     name::{AsName, Name},
     proc_macro::ProcMacroExpander,
-    HirFileId, MacroCallId, MacroCallKind, MacroDefId, MacroDefKind,
+    HirFileId, MacroCallId, MacroDefId, MacroDefKind,
 };
 use hir_expand::{InFile, MacroCallLoc};
 use rustc_hash::{FxHashMap, FxHashSet};
@@ -24,38 +24,43 @@ use tt::{Leaf, TokenTree};
 use crate::{
     attr::Attrs,
     db::DefDatabase,
+    item_attr_as_call_id,
     item_scope::{ImportType, PerNsGlobImports},
     item_tree::{
         self, FileItemTreeId, ItemTree, ItemTreeId, MacroCall, MacroRules, Mod, ModItem, ModKind,
         StructDefKind,
     },
+    macro_call_as_call_id,
     nameres::{
         diagnostics::DefDiagnostic, mod_resolution::ModDir, path_resolution::ReachedFixedPoint,
-        BuiltinShadowMode, CrateDefMap, ModuleData, ModuleOrigin, ResolveMode,
+        BuiltinShadowMode, DefMap, ModuleData, ModuleOrigin, ResolveMode,
     },
     path::{ImportAlias, ModPath, PathKind},
     per_ns::PerNs,
     visibility::{RawVisibility, Visibility},
-    AdtId, AsMacroCall, AstId, AstIdWithPath, ConstLoc, ContainerId, EnumLoc, EnumVariantId,
-    FunctionLoc, ImplLoc, Intern, LocalModuleId, ModuleDefId, ModuleId, StaticLoc, StructLoc,
-    TraitLoc, TypeAliasLoc, UnionLoc,
+    AdtId, AstId, AstIdWithPath, ConstLoc, ContainerId, EnumLoc, EnumVariantId, FunctionLoc,
+    ImplLoc, Intern, LocalModuleId, ModuleDefId, StaticLoc, StructLoc, TraitLoc, TypeAliasLoc,
+    UnionLoc, UnresolvedMacro,
 };
 
 const GLOB_RECURSION_LIMIT: usize = 100;
 const EXPANSION_DEPTH_LIMIT: usize = 128;
 const FIXED_POINT_LIMIT: usize = 8192;
 
-pub(super) fn collect_defs(db: &dyn DefDatabase, mut def_map: CrateDefMap) -> CrateDefMap {
+pub(super) fn collect_defs(
+    db: &dyn DefDatabase,
+    mut def_map: DefMap,
+    block: Option<AstId<ast::BlockExpr>>,
+) -> DefMap {
     let crate_graph = db.crate_graph();
 
     // populate external prelude
     for dep in &crate_graph[def_map.krate].dependencies {
         log::debug!("crate dep {:?} -> {:?}", dep.name, dep.crate_id);
         let dep_def_map = db.crate_def_map(dep.crate_id);
-        def_map.extern_prelude.insert(
-            dep.as_name(),
-            ModuleId { krate: dep.crate_id, local_id: dep_def_map.root }.into(),
-        );
+        def_map
+            .extern_prelude
+            .insert(dep.as_name(), dep_def_map.module_id(dep_def_map.root).into());
 
         // look for the prelude
         // If the dependency defines a prelude, we overwrite an already defined
@@ -93,6 +98,14 @@ pub(super) fn collect_defs(db: &dyn DefDatabase, mut def_map: CrateDefMap) -> Cr
         exports_proc_macros: false,
         from_glob_import: Default::default(),
     };
+    match block {
+        Some(block) => {
+            collector.seed_with_inner(block);
+        }
+        None => {
+            collector.seed_with_top_level();
+        }
+    }
     collector.collect();
     collector.finish()
 }
@@ -210,7 +223,7 @@ struct DefData<'a> {
 /// Walks the tree of module recursively
 struct DefCollector<'a> {
     db: &'a dyn DefDatabase,
-    def_map: CrateDefMap,
+    def_map: DefMap,
     glob_imports: FxHashMap<LocalModuleId, Vec<(LocalModuleId, Visibility)>>,
     unresolved_imports: Vec<ImportDirective>,
     resolved_imports: Vec<ImportDirective>,
@@ -228,7 +241,7 @@ struct DefCollector<'a> {
 }
 
 impl DefCollector<'_> {
-    fn collect(&mut self) {
+    fn seed_with_top_level(&mut self) {
         let file_id = self.db.crate_graph()[self.def_map.krate].root_file_id;
         let item_tree = self.db.item_tree(file_id.into());
         let module_id = self.def_map.root;
@@ -248,7 +261,30 @@ impl DefCollector<'_> {
             }
             .collect(item_tree.top_level_items());
         }
+    }
 
+    fn seed_with_inner(&mut self, block: AstId<ast::BlockExpr>) {
+        let item_tree = self.db.item_tree(block.file_id);
+        let module_id = self.def_map.root;
+        self.def_map.modules[module_id].origin = ModuleOrigin::BlockExpr { block };
+        if item_tree
+            .top_level_attrs(self.db, self.def_map.krate)
+            .cfg()
+            .map_or(true, |cfg| self.cfg_options.check(&cfg) != Some(false))
+        {
+            ModCollector {
+                def_collector: &mut *self,
+                macro_depth: 0,
+                module_id,
+                file_id: block.file_id,
+                item_tree: &item_tree,
+                mod_dir: ModDir::root(),
+            }
+            .collect(item_tree.inner_items_of_block(block.value));
+        }
+    }
+
+    fn collect(&mut self) {
         // main name resolution fixed-point loop.
         let mut i = 0;
         loop {
@@ -296,11 +332,9 @@ impl DefCollector<'_> {
             // exported in type/value namespace. This function reduces the visibility of all items
             // in the crate root that aren't proc macros.
             let root = self.def_map.root;
+            let module_id = self.def_map.module_id(root);
             let root = &mut self.def_map.modules[root];
-            root.scope.censor_non_proc_macros(ModuleId {
-                krate: self.def_map.krate,
-                local_id: self.def_map.root,
-            });
+            root.scope.censor_non_proc_macros(module_id);
         }
     }
 
@@ -542,7 +576,7 @@ impl DefCollector<'_> {
                     } else if m.krate != self.def_map.krate {
                         mark::hit!(glob_across_crates);
                         // glob import from other crate => we can just import everything once
-                        let item_map = self.db.crate_def_map(m.krate);
+                        let item_map = m.def_map(self.db);
                         let scope = &item_map[m.local_id].scope;
 
                         // Module scoped macros is included
@@ -560,7 +594,13 @@ impl DefCollector<'_> {
                         // glob import from same crate => we do an initial
                         // import, and then need to propagate any further
                         // additions
-                        let scope = &self.def_map[m.local_id].scope;
+                        let def_map;
+                        let scope = if m.block == self.def_map.block_id() {
+                            &self.def_map[m.local_id].scope
+                        } else {
+                            def_map = m.def_map(self.db);
+                            &def_map[m.local_id].scope
+                        };
 
                         // Module scoped macros is included
                         let items = scope
@@ -570,7 +610,7 @@ impl DefCollector<'_> {
                                 (
                                     n,
                                     res.filter_visibility(|v| {
-                                        v.is_visible_from_def_map(&self.def_map, module_id)
+                                        v.is_visible_from_def_map(self.db, &self.def_map, module_id)
                                     }),
                                 )
                             })
@@ -617,7 +657,7 @@ impl DefCollector<'_> {
                 }
             }
         } else {
-            match import.path.segments.last() {
+            match import.path.segments().last() {
                 Some(last_segment) => {
                     let name = match &import.alias {
                         Some(ImportAlias::Alias(name)) => Some(name.clone()),
@@ -723,7 +763,7 @@ impl DefCollector<'_> {
             .filter(|(glob_importing_module, _)| {
                 // we know all resolutions have the same visibility (`vis`), so we
                 // just need to check that once
-                vis.is_visible_from_def_map(&self.def_map, *glob_importing_module)
+                vis.is_visible_from_def_map(self.db, &self.def_map, *glob_importing_module)
             })
             .cloned()
             .collect::<Vec<_>>();
@@ -752,8 +792,11 @@ impl DefCollector<'_> {
                 return false;
             }
 
-            if let Some(call_id) =
-                directive.ast_id.as_call_id(self.db, self.def_map.krate, |path| {
+            match macro_call_as_call_id(
+                &directive.ast_id,
+                self.db,
+                self.def_map.krate,
+                |path| {
                     let resolved_res = self.def_map.resolve_path_fp_with_macro(
                         self.db,
                         ResolveMode::Other,
@@ -762,24 +805,29 @@ impl DefCollector<'_> {
                         BuiltinShadowMode::Module,
                     );
                     resolved_res.resolved_def.take_macros()
-                })
-            {
-                resolved.push((directive.module_id, call_id, directive.depth));
-                res = ReachedFixedPoint::No;
-                return false;
+                },
+                &mut |_err| (),
+            ) {
+                Ok(Ok(call_id)) => {
+                    resolved.push((directive.module_id, call_id, directive.depth));
+                    res = ReachedFixedPoint::No;
+                    return false;
+                }
+                Err(UnresolvedMacro) | Ok(Err(_)) => {}
             }
 
             true
         });
         attribute_macros.retain(|directive| {
-            if let Some(call_id) =
-                directive.ast_id.as_call_id(self.db, self.def_map.krate, |path| {
-                    self.resolve_attribute_macro(&directive, &path)
-                })
-            {
-                resolved.push((directive.module_id, call_id, 0));
-                res = ReachedFixedPoint::No;
-                return false;
+            match item_attr_as_call_id(&directive.ast_id, self.db, self.def_map.krate, |path| {
+                self.resolve_attribute_macro(&directive, &path)
+            }) {
+                Ok(call_id) => {
+                    resolved.push((directive.module_id, call_id, 0));
+                    res = ReachedFixedPoint::No;
+                    return false;
+                }
+                Err(UnresolvedMacro) => (),
             }
 
             true
@@ -859,12 +907,13 @@ impl DefCollector<'_> {
         .collect(item_tree.top_level_items());
     }
 
-    fn finish(mut self) -> CrateDefMap {
+    fn finish(mut self) -> DefMap {
         // Emit diagnostics for all remaining unexpanded macros.
 
         for directive in &self.unexpanded_macros {
             let mut error = None;
-            directive.ast_id.as_call_id_with_errors(
+            match macro_call_as_call_id(
+                &directive.ast_id,
                 self.db,
                 self.def_map.krate,
                 |path| {
@@ -880,15 +929,15 @@ impl DefCollector<'_> {
                 &mut |e| {
                     error.get_or_insert(e);
                 },
-            );
-
-            if let Some(err) = error {
-                self.def_map.diagnostics.push(DefDiagnostic::macro_error(
-                    directive.module_id,
-                    MacroCallKind::FnLike(directive.ast_id.ast_id),
-                    err.to_string(),
-                ));
-            }
+            ) {
+                Ok(_) => (),
+                Err(UnresolvedMacro) => {
+                    self.def_map.diagnostics.push(DefDiagnostic::unresolved_macro_call(
+                        directive.module_id,
+                        directive.ast_id.ast_id,
+                    ));
+                }
+            };
         }
 
         // Emit diagnostics for all remaining unresolved imports.
@@ -918,7 +967,7 @@ impl DefCollector<'_> {
                 let item_tree = self.db.item_tree(import.file_id);
                 let import_data = &item_tree[import.value];
 
-                match (import_data.path.segments.first(), &import_data.path.kind) {
+                match (import_data.path.segments().first(), &import_data.path.kind) {
                     (Some(krate), PathKind::Plain) | (Some(krate), PathKind::Abs) => {
                         if diagnosed_extern_crates.contains(krate) {
                             continue;
@@ -993,8 +1042,7 @@ impl ModCollector<'_, '_> {
                     continue;
                 }
             }
-            let module =
-                ModuleId { krate: self.def_collector.def_map.krate, local_id: self.module_id };
+            let module = self.def_collector.def_map.module_id(self.module_id);
             let container = ContainerId::ModuleId(module);
 
             let mut def = None;
@@ -1061,10 +1109,7 @@ impl ModCollector<'_, '_> {
                     }
                 }
                 ModItem::Impl(imp) => {
-                    let module = ModuleId {
-                        krate: self.def_collector.def_map.krate,
-                        local_id: self.module_id,
-                    };
+                    let module = self.def_collector.def_map.module_id(self.module_id);
                     let container = ContainerId::ModuleId(module);
                     let impl_id = ImplLoc { container, id: ItemTreeId::new(self.file_id, imp) }
                         .intern(self.def_collector.db);
@@ -1245,12 +1290,8 @@ impl ModCollector<'_, '_> {
             // out of line module, resolve, parse and recurse
             ModKind::Outline {} => {
                 let ast_id = AstId::new(self.file_id, module.ast_id);
-                match self.mod_dir.resolve_declaration(
-                    self.def_collector.db,
-                    self.file_id,
-                    &module.name,
-                    path_attr,
-                ) {
+                let db = self.def_collector.db;
+                match self.mod_dir.resolve_declaration(db, self.file_id, &module.name, path_attr) {
                     Ok((file_id, is_mod_rs, mod_dir)) => {
                         let module_id = self.push_child_module(
                             module.name.clone(),
@@ -1258,7 +1299,7 @@ impl ModCollector<'_, '_> {
                             Some((file_id, is_mod_rs)),
                             &self.item_tree[module.visibility],
                         );
-                        let item_tree = self.def_collector.db.item_tree(file_id.into());
+                        let item_tree = db.item_tree(file_id.into());
                         ModCollector {
                             def_collector: &mut *self.def_collector,
                             macro_depth: self.macro_depth,
@@ -1268,7 +1309,12 @@ impl ModCollector<'_, '_> {
                             mod_dir,
                         }
                         .collect(item_tree.top_level_items());
-                        if is_macro_use {
+                        if is_macro_use
+                            || item_tree
+                                .top_level_attrs(db, self.def_collector.def_map.krate)
+                                .by_key("macro_use")
+                                .exists()
+                        {
                             self.import_all_legacy_macros(module_id);
                         }
                     }
@@ -1307,7 +1353,7 @@ impl ModCollector<'_, '_> {
             modules[res].scope.define_legacy_macro(name, mac)
         }
         modules[self.module_id].children.insert(name.clone(), res);
-        let module = ModuleId { krate: self.def_collector.def_map.krate, local_id: res };
+        let module = self.def_collector.def_map.module_id(res);
         let def: ModuleDefId = module.into();
         self.def_collector.def_map.modules[self.module_id].scope.define_def(def);
         self.def_collector.update(
@@ -1411,13 +1457,21 @@ impl ModCollector<'_, '_> {
         let mut ast_id = AstIdWithPath::new(self.file_id, mac.ast_id, mac.path.clone());
 
         // Case 1: try to resolve in legacy scope and expand macro_rules
-        if let Some(macro_call_id) =
-            ast_id.as_call_id(self.def_collector.db, self.def_collector.def_map.krate, |path| {
+        if let Ok(Ok(macro_call_id)) = macro_call_as_call_id(
+            &ast_id,
+            self.def_collector.db,
+            self.def_collector.def_map.krate,
+            |path| {
                 path.as_ident().and_then(|name| {
-                    self.def_collector.def_map[self.module_id].scope.get_legacy_macro(&name)
+                    self.def_collector.def_map.with_ancestor_maps(
+                        self.def_collector.db,
+                        self.module_id,
+                        &mut |map, module| map[module].scope.get_legacy_macro(&name),
+                    )
                 })
-            })
-        {
+            },
+            &mut |_err| (),
+        ) {
             self.def_collector.unexpanded_macros.push(MacroDirective {
                 module_id: self.module_id,
                 ast_id,
@@ -1470,11 +1524,10 @@ impl ModCollector<'_, '_> {
 mod tests {
     use crate::{db::DefDatabase, test_db::TestDB};
     use base_db::{fixture::WithFixture, SourceDatabase};
-    use la_arena::Arena;
 
     use super::*;
 
-    fn do_collect_defs(db: &dyn DefDatabase, def_map: CrateDefMap) -> CrateDefMap {
+    fn do_collect_defs(db: &dyn DefDatabase, def_map: DefMap) -> DefMap {
         let mut collector = DefCollector {
             db,
             def_map,
@@ -1489,28 +1542,17 @@ mod tests {
             exports_proc_macros: false,
             from_glob_import: Default::default(),
         };
+        collector.seed_with_top_level();
         collector.collect();
         collector.def_map
     }
 
-    fn do_resolve(code: &str) -> CrateDefMap {
+    fn do_resolve(code: &str) -> DefMap {
         let (db, _file_id) = TestDB::with_single_file(&code);
         let krate = db.test_crate();
 
-        let def_map = {
-            let edition = db.crate_graph()[krate].edition;
-            let mut modules: Arena<ModuleData> = Arena::default();
-            let root = modules.alloc(ModuleData::default());
-            CrateDefMap {
-                krate,
-                edition,
-                extern_prelude: FxHashMap::default(),
-                prelude: None,
-                root,
-                modules,
-                diagnostics: Vec::new(),
-            }
-        };
+        let edition = db.crate_graph()[krate].edition;
+        let def_map = DefMap::empty(krate, edition);
         do_collect_defs(&db, def_map)
     }
 
diff --git a/crates/hir_def/src/nameres/path_resolution.rs b/crates/hir_def/src/nameres/path_resolution.rs
index 88e10574e..dd1db0094 100644
--- a/crates/hir_def/src/nameres/path_resolution.rs
+++ b/crates/hir_def/src/nameres/path_resolution.rs
@@ -10,20 +10,19 @@
 //!
 //! `ReachedFixedPoint` signals about this.
 
-use std::iter::successors;
-
 use base_db::Edition;
+use hir_expand::name;
 use hir_expand::name::Name;
 use test_utils::mark;
 
 use crate::{
     db::DefDatabase,
     item_scope::BUILTIN_SCOPE,
-    nameres::{BuiltinShadowMode, CrateDefMap},
+    nameres::{BuiltinShadowMode, DefMap},
     path::{ModPath, PathKind},
     per_ns::PerNs,
     visibility::{RawVisibility, Visibility},
-    AdtId, CrateId, EnumVariantId, LocalModuleId, ModuleDefId, ModuleId,
+    AdtId, CrateId, EnumVariantId, LocalModuleId, ModuleDefId,
 };
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
@@ -61,8 +60,12 @@ impl ResolvePathResult {
     }
 }
 
-impl CrateDefMap {
+impl DefMap {
     pub(super) fn resolve_name_in_extern_prelude(&self, name: &Name) -> PerNs {
+        if name == &name!(self) {
+            mark::hit!(extern_crate_self_as);
+            return PerNs::types(self.module_id(self.root).into(), Visibility::Public);
+        }
         self.extern_prelude
             .get(name)
             .map_or(PerNs::none(), |&it| PerNs::types(it, Visibility::Public))
@@ -74,7 +77,7 @@ impl CrateDefMap {
         original_module: LocalModuleId,
         visibility: &RawVisibility,
     ) -> Option<Visibility> {
-        match visibility {
+        let mut vis = match visibility {
             RawVisibility::Module(path) => {
                 let (result, remaining) =
                     self.resolve_path(db, original_module, &path, BuiltinShadowMode::Module);
@@ -83,15 +86,28 @@ impl CrateDefMap {
                 }
                 let types = result.take_types()?;
                 match types {
-                    ModuleDefId::ModuleId(m) => Some(Visibility::Module(m)),
+                    ModuleDefId::ModuleId(m) => Visibility::Module(m),
                     _ => {
                         // error: visibility needs to refer to module
-                        None
+                        return None;
                     }
                 }
             }
-            RawVisibility::Public => Some(Visibility::Public),
+            RawVisibility::Public => Visibility::Public,
+        };
+
+        // In block expressions, `self` normally refers to the containing non-block module, and
+        // `super` to its parent (etc.). However, visibilities must only refer to a module in the
+        // DefMap they're written in, so we restrict them when that happens.
+        if let Visibility::Module(m) = vis {
+            if self.block_id() != m.block {
+                mark::hit!(adjust_vis_in_block_def_map);
+                vis = Visibility::Module(self.module_id(self.root()));
+                log::debug!("visibility {:?} points outside DefMap, adjusting to {:?}", m, vis);
+            }
         }
+
+        Some(vis)
     }
 
     // Returns Yes if we are sure that additions to `ItemMap` wouldn't change
@@ -100,30 +116,69 @@ impl CrateDefMap {
         &self,
         db: &dyn DefDatabase,
         mode: ResolveMode,
+        mut original_module: LocalModuleId,
+        path: &ModPath,
+        shadow: BuiltinShadowMode,
+    ) -> ResolvePathResult {
+        let mut result = ResolvePathResult::empty(ReachedFixedPoint::No);
+
+        let mut arc;
+        let mut current_map = self;
+        loop {
+            let new = current_map.resolve_path_fp_with_macro_single(
+                db,
+                mode,
+                original_module,
+                path,
+                shadow,
+            );
+
+            // Merge `new` into `result`.
+            result.resolved_def = result.resolved_def.or(new.resolved_def);
+            if result.reached_fixedpoint == ReachedFixedPoint::No {
+                result.reached_fixedpoint = new.reached_fixedpoint;
+            }
+            // FIXME: this doesn't seem right; what if the different namespace resolutions come from different crates?
+            result.krate = result.krate.or(new.krate);
+            result.segment_index = match (result.segment_index, new.segment_index) {
+                (Some(idx), None) => Some(idx),
+                (Some(old), Some(new)) => Some(old.max(new)),
+                (None, new) => new,
+            };
+
+            match &current_map.block {
+                Some(block) => {
+                    original_module = block.parent.local_id;
+                    arc = block.parent.def_map(db);
+                    current_map = &*arc;
+                }
+                None => return result,
+            }
+        }
+    }
+
+    pub(super) fn resolve_path_fp_with_macro_single(
+        &self,
+        db: &dyn DefDatabase,
+        mode: ResolveMode,
         original_module: LocalModuleId,
         path: &ModPath,
         shadow: BuiltinShadowMode,
     ) -> ResolvePathResult {
-        let mut segments = path.segments.iter().enumerate();
+        let mut segments = path.segments().iter().enumerate();
         let mut curr_per_ns: PerNs = match path.kind {
             PathKind::DollarCrate(krate) => {
                 if krate == self.krate {
                     mark::hit!(macro_dollar_crate_self);
-                    PerNs::types(
-                        ModuleId { krate: self.krate, local_id: self.root }.into(),
-                        Visibility::Public,
-                    )
+                    PerNs::types(self.crate_root(db).into(), Visibility::Public)
                 } else {
                     let def_map = db.crate_def_map(krate);
-                    let module = ModuleId { krate, local_id: def_map.root };
+                    let module = def_map.module_id(def_map.root);
                     mark::hit!(macro_dollar_crate_other);
                     PerNs::types(module.into(), Visibility::Public)
                 }
             }
-            PathKind::Crate => PerNs::types(
-                ModuleId { krate: self.krate, local_id: self.root }.into(),
-                Visibility::Public,
-            ),
+            PathKind::Crate => PerNs::types(self.crate_root(db).into(), Visibility::Public),
             // plain import or absolute path in 2015: crate-relative with
             // fallback to extern prelude (with the simplification in
             // rust-lang/rust#57745)
@@ -151,23 +206,49 @@ impl CrateDefMap {
                 // BuiltinShadowMode wasn't Module, then we need to try
                 // resolving it as a builtin.
                 let prefer_module =
-                    if path.segments.len() == 1 { shadow } else { BuiltinShadowMode::Module };
+                    if path.segments().len() == 1 { shadow } else { BuiltinShadowMode::Module };
 
                 log::debug!("resolving {:?} in module", segment);
                 self.resolve_name_in_module(db, original_module, &segment, prefer_module)
             }
             PathKind::Super(lvl) => {
-                let m = successors(Some(original_module), |m| self.modules[*m].parent)
-                    .nth(lvl as usize);
-                if let Some(local_id) = m {
-                    PerNs::types(
-                        ModuleId { krate: self.krate, local_id }.into(),
-                        Visibility::Public,
-                    )
-                } else {
-                    log::debug!("super path in root module");
-                    return ResolvePathResult::empty(ReachedFixedPoint::Yes);
+                let mut module = original_module;
+                for i in 0..lvl {
+                    match self.modules[module].parent {
+                        Some(it) => module = it,
+                        None => match &self.block {
+                            Some(block) => {
+                                // Look up remaining path in parent `DefMap`
+                                let new_path = ModPath::from_segments(
+                                    PathKind::Super(lvl - i),
+                                    path.segments().to_vec(),
+                                );
+                                log::debug!("`super` path: {} -> {} in parent map", path, new_path);
+                                return block.parent.def_map(db).resolve_path_fp_with_macro(
+                                    db,
+                                    mode,
+                                    block.parent.local_id,
+                                    &new_path,
+                                    shadow,
+                                );
+                            }
+                            None => {
+                                log::debug!("super path in root module");
+                                return ResolvePathResult::empty(ReachedFixedPoint::Yes);
+                            }
+                        },
+                    }
                 }
+
+                // Resolve `self` to the containing crate-rooted module if we're a block
+                self.with_ancestor_maps(db, module, &mut |def_map, module| {
+                    if def_map.block.is_some() {
+                        None // keep ascending
+                    } else {
+                        Some(PerNs::types(def_map.module_id(module).into(), Visibility::Public))
+                    }
+                })
+                .expect("block DefMap not rooted in crate DefMap")
             }
             PathKind::Abs => {
                 // 2018-style absolute path -- only extern prelude
@@ -201,12 +282,12 @@ impl CrateDefMap {
             curr_per_ns = match curr {
                 ModuleDefId::ModuleId(module) => {
                     if module.krate != self.krate {
-                        let path = ModPath {
-                            segments: path.segments[i..].to_vec(),
-                            kind: PathKind::Super(0),
-                        };
+                        let path = ModPath::from_segments(
+                            PathKind::Super(0),
+                            path.segments()[i..].iter().cloned(),
+                        );
                         log::debug!("resolving {:?} in other crate", path);
-                        let defp_map = db.crate_def_map(module.krate);
+                        let defp_map = module.def_map(db);
                         let (def, s) = defp_map.resolve_path(db, module.local_id, &path, shadow);
                         return ResolvePathResult::with(
                             def,
@@ -216,8 +297,16 @@ impl CrateDefMap {
                         );
                     }
 
+                    let def_map;
+                    let module_data = if module.block == self.block_id() {
+                        &self[module.local_id]
+                    } else {
+                        def_map = module.def_map(db);
+                        &def_map[module.local_id]
+                    };
+
                     // Since it is a qualified path here, it should not contains legacy macros
-                    self[module.local_id].scope.get(&segment)
+                    module_data.scope.get(&segment)
                 }
                 ModuleDefId::AdtId(AdtId::EnumId(e)) => {
                     // enum variant
@@ -319,7 +408,7 @@ impl CrateDefMap {
                 self
             } else {
                 // Extend lifetime
-                keep = db.crate_def_map(prelude.krate);
+                keep = prelude.def_map(db);
                 &keep
             };
             def_map[prelude.local_id].scope.get(name)
diff --git a/crates/hir_def/src/nameres/tests.rs b/crates/hir_def/src/nameres/tests.rs
index c459fa66d..bd3e2701b 100644
--- a/crates/hir_def/src/nameres/tests.rs
+++ b/crates/hir_def/src/nameres/tests.rs
@@ -11,17 +11,24 @@ use base_db::{fixture::WithFixture, SourceDatabase};
 use expect_test::{expect, Expect};
 use test_utils::mark;
 
-use crate::{db::DefDatabase, nameres::*, test_db::TestDB};
+use crate::{db::DefDatabase, test_db::TestDB};
 
-fn compute_crate_def_map(ra_fixture: &str) -> Arc<CrateDefMap> {
+use super::DefMap;
+
+fn compute_crate_def_map(ra_fixture: &str) -> Arc<DefMap> {
     let db = TestDB::with_files(ra_fixture);
     let krate = db.crate_graph().iter().next().unwrap();
     db.crate_def_map(krate)
 }
 
+fn render_crate_def_map(ra_fixture: &str) -> String {
+    let db = TestDB::with_files(ra_fixture);
+    let krate = db.crate_graph().iter().next().unwrap();
+    db.crate_def_map(krate).dump(&db)
+}
+
 fn check(ra_fixture: &str, expect: Expect) {
-    let def_map = compute_crate_def_map(ra_fixture);
-    let actual = def_map.dump();
+    let actual = render_crate_def_map(ra_fixture);
     expect.assert_eq(&actual);
 }
 
diff --git a/crates/hir_def/src/nameres/tests/diagnostics.rs b/crates/hir_def/src/nameres/tests/diagnostics.rs
index 58d69d3c6..e8e72e5ef 100644
--- a/crates/hir_def/src/nameres/tests/diagnostics.rs
+++ b/crates/hir_def/src/nameres/tests/diagnostics.rs
@@ -62,6 +62,22 @@ fn unresolved_extern_crate() {
 }
 
 #[test]
+fn extern_crate_self_as() {
+    mark::check!(extern_crate_self_as);
+    check_diagnostics(
+        r"
+        //- /lib.rs
+          extern crate doesnotexist;
+        //^^^^^^^^^^^^^^^^^^^^^^^^^^ unresolved extern crate
+        // Should not error.
+        extern crate self as foo;
+        struct Foo;
+        use foo::Foo as Bar;
+        ",
+    );
+}
+
+#[test]
 fn dedup_unresolved_import_from_unresolved_crate() {
     check_diagnostics(
         r"
diff --git a/crates/hir_def/src/nameres/tests/macros.rs b/crates/hir_def/src/nameres/tests/macros.rs
index e5e9e8ca1..36ed5e8ce 100644
--- a/crates/hir_def/src/nameres/tests/macros.rs
+++ b/crates/hir_def/src/nameres/tests/macros.rs
@@ -391,11 +391,21 @@ foo!(ok_shadow);
 mod m4;
 bar!(OkMacroUse);
 
+mod m5;
+baz!(OkMacroUseInner);
+
 //- /m3/m4.rs
 foo!(ok_shadow_deep);
 macro_rules! bar {
     ($x:ident) => { struct $x; }
 }
+//- /m3/m5.rs
+#![macro_use]
+macro_rules! baz {
+    ($x:ident) => { struct $x; }
+}
+
+
 "#,
         expect![[r#"
             crate
@@ -423,11 +433,15 @@ macro_rules! bar {
             crate::m3
             OkAfterInside: t v
             OkMacroUse: t v
+            OkMacroUseInner: t v
             m4: t
+            m5: t
             ok_shadow: v
 
             crate::m3::m4
             ok_shadow_deep: v
+
+            crate::m3::m5
         "#]],
     );
 }