1 files changed, 193 insertions, 20 deletions

diff --git a/crates/ra_hir/src/nameres/lower.rs b/crates/ra_hir/src/nameres/lower.rs
index 35bdbafbf..6bca14444 100644
--- a/crates/ra_hir/src/nameres/lower.rs
+++ b/crates/ra_hir/src/nameres/lower.rs
@@ -1,10 +1,11 @@
 use std::sync::Arc;
 
 use ra_syntax::{
-    TextRange, SyntaxKind, AstNode,
+    TextRange, SyntaxKind, AstNode, SourceFile, TreeArc,
     ast::{self, ModuleItemOwner},
 };
-use ra_db::{FileId, SourceRootId};
+use ra_db::{SourceRootId, LocalSyntaxPtr};
+use ra_arena::{Arena, RawId, impl_arena_id, map::ArenaMap};
 
 use crate::{
     SourceItemId, SourceFileItemId, Path, ModuleSource, HirDatabase, Name, SourceFileItems,
@@ -139,12 +140,12 @@ impl InputModuleItems {
     fn add_use_item(&mut self, file_items: &SourceFileItems, item: &ast::UseItem) {
         let file_item_id = file_items.id_of_unchecked(item.syntax());
         let start_offset = item.syntax().range().start();
-        Path::expand_use_item(item, |path, range| {
-            let kind = match range {
+        Path::expand_use_item(item, |path, segment| {
+            let kind = match segment {
                 None => ImportKind::Glob,
-                Some(range) => ImportKind::Named(NamedImport {
+                Some(segment) => ImportKind::Named(NamedImport {
                     file_item_id,
-                    relative_range: range - start_offset,
+                    relative_range: segment.syntax().range() - start_offset,
                 }),
             };
             self.imports.push(Import { kind, path })
@@ -199,22 +200,194 @@ pub struct NamedImport {
     pub relative_range: TextRange,
 }
 
-impl NamedImport {
-    // FIXME: this is only here for one use-case in completion. Seems like a
-    // pretty gross special case.
-    pub fn range(&self, db: &impl HirDatabase, file_id: FileId) -> TextRange {
-        let source_item_id = SourceItemId {
-            file_id: file_id.into(),
-            item_id: Some(self.file_item_id),
-        };
-        let syntax = db.file_item(source_item_id);
-        let offset = syntax.range().start();
-        self.relative_range + offset
-    }
-}
-
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub(super) enum ImportKind {
     Glob,
     Named(NamedImport),
 }
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub struct LoweredImport(RawId);
+impl_arena_id!(LoweredImport);
+
+#[derive(Debug, PartialEq, Eq)]
+pub(super) struct ImportData {
+    pub(super) path: Path,
+    pub(super) is_glob: bool,
+}
+
+#[derive(Debug, Default, PartialEq, Eq)]
+pub struct LoweredModule {
+    pub(super) items: Vec<ModuleItem>,
+    pub(super) imports: Arena<LoweredImport, ImportData>,
+}
+
+#[derive(Debug, Default, PartialEq, Eq)]
+pub struct ImportSourceMap {
+    map: ArenaMap<LoweredImport, LocalSyntaxPtr>,
+}
+
+impl ImportSourceMap {
+    fn insert(&mut self, import: LoweredImport, segment: &ast::PathSegment) {
+        self.map
+            .insert(import, LocalSyntaxPtr::new(segment.syntax()))
+    }
+
+    pub fn get(&self, source: &ModuleSource, import: LoweredImport) -> TreeArc<ast::PathSegment> {
+        let file = match source {
+            ModuleSource::SourceFile(file) => &*file,
+            ModuleSource::Module(m) => m.syntax().ancestors().find_map(SourceFile::cast).unwrap(),
+        };
+
+        ast::PathSegment::cast(&self.map[import].resolve(file))
+            .unwrap()
+            .to_owned()
+    }
+}
+
+impl LoweredModule {
+    pub(crate) fn lower_module_module_query(
+        db: &impl HirDatabase,
+        source_root_id: SourceRootId,
+        module_id: ModuleId,
+    ) -> Arc<LoweredModule> {
+        db.lower_module(source_root_id, module_id).0
+    }
+
+    pub(crate) fn lower_module_source_map_query(
+        db: &impl HirDatabase,
+        source_root_id: SourceRootId,
+        module_id: ModuleId,
+    ) -> Arc<ImportSourceMap> {
+        db.lower_module(source_root_id, module_id).1
+    }
+
+    pub(crate) fn lower_module_query(
+        db: &impl HirDatabase,
+        source_root_id: SourceRootId,
+        module_id: ModuleId,
+    ) -> (Arc<LoweredModule>, Arc<ImportSourceMap>) {
+        let module_tree = db.module_tree(source_root_id);
+        let source = module_id.source(&module_tree);
+        let file_id = source.file_id;
+        let source = ModuleSource::from_source_item_id(db, source);
+        let mut source_map = ImportSourceMap::default();
+        let mut res = LoweredModule::default();
+        match source {
+            ModuleSource::SourceFile(it) => res.fill(
+                &mut source_map,
+                db,
+                source_root_id,
+                module_id,
+                file_id,
+                &mut it.items_with_macros(),
+            ),
+            ModuleSource::Module(it) => {
+                if let Some(item_list) = it.item_list() {
+                    res.fill(
+                        &mut source_map,
+                        db,
+                        source_root_id,
+                        module_id,
+                        file_id,
+                        &mut item_list.items_with_macros(),
+                    )
+                }
+            }
+        };
+        (Arc::new(res), Arc::new(source_map))
+    }
+
+    fn fill(
+        &mut self,
+        source_map: &mut ImportSourceMap,
+        db: &impl HirDatabase,
+        source_root_id: SourceRootId,
+        module_id: ModuleId,
+        file_id: HirFileId,
+        items: &mut Iterator<Item = ast::ItemOrMacro>,
+    ) {
+        let file_items = db.file_items(file_id);
+
+        for item in items {
+            match item {
+                ast::ItemOrMacro::Item(it) => {
+                    self.add_item(source_map, file_id, &file_items, it);
+                }
+                ast::ItemOrMacro::Macro(macro_call) => {
+                    let item_id = file_items.id_of_unchecked(macro_call.syntax());
+                    let loc = MacroCallLoc {
+                        source_root_id,
+                        module_id,
+                        source_item_id: SourceItemId {
+                            file_id,
+                            item_id: Some(item_id),
+                        },
+                    };
+                    let id = loc.id(db);
+                    let file_id = HirFileId::from(id);
+                    let file_items = db.file_items(file_id);
+                    //FIXME: expand recursively
+                    for item in db.hir_source_file(file_id).items() {
+                        self.add_item(source_map, file_id, &file_items, item);
+                    }
+                }
+            }
+        }
+    }
+
+    fn add_item(
+        &mut self,
+        source_map: &mut ImportSourceMap,
+        file_id: HirFileId,
+        file_items: &SourceFileItems,
+        item: &ast::ModuleItem,
+    ) -> Option<()> {
+        match item.kind() {
+            ast::ModuleItemKind::StructDef(it) => {
+                self.items.push(ModuleItem::new(file_id, file_items, it)?)
+            }
+            ast::ModuleItemKind::EnumDef(it) => {
+                self.items.push(ModuleItem::new(file_id, file_items, it)?)
+            }
+            ast::ModuleItemKind::FnDef(it) => {
+                self.items.push(ModuleItem::new(file_id, file_items, it)?)
+            }
+            ast::ModuleItemKind::TraitDef(it) => {
+                self.items.push(ModuleItem::new(file_id, file_items, it)?)
+            }
+            ast::ModuleItemKind::TypeDef(it) => {
+                self.items.push(ModuleItem::new(file_id, file_items, it)?)
+            }
+            ast::ModuleItemKind::ImplBlock(_) => {
+                // impls don't define items
+            }
+            ast::ModuleItemKind::UseItem(it) => self.add_use_item(source_map, it),
+            ast::ModuleItemKind::ExternCrateItem(_) => {
+                // TODO
+            }
+            ast::ModuleItemKind::ConstDef(it) => {
+                self.items.push(ModuleItem::new(file_id, file_items, it)?)
+            }
+            ast::ModuleItemKind::StaticDef(it) => {
+                self.items.push(ModuleItem::new(file_id, file_items, it)?)
+            }
+            ast::ModuleItemKind::Module(it) => {
+                self.items.push(ModuleItem::new(file_id, file_items, it)?)
+            }
+        }
+        Some(())
+    }
+
+    fn add_use_item(&mut self, source_map: &mut ImportSourceMap, item: &ast::UseItem) {
+        Path::expand_use_item(item, |path, segment| {
+            let import = self.imports.alloc(ImportData {
+                path,
+                is_glob: segment.is_none(),
+            });
+            if let Some(segment) = segment {
+                source_map.insert(import, segment)
+            }
+        })
+    }
+}