4 files changed, 102 insertions, 28 deletions

diff --git a/crates/ra_hir/src/code_model_api.rs b/crates/ra_hir/src/code_model_api.rs
index eca7d0225..0c7f743d4 100644
--- a/crates/ra_hir/src/code_model_api.rs
+++ b/crates/ra_hir/src/code_model_api.rs
@@ -1,6 +1,7 @@
-use ra_db::{CrateId, Cancelable};
+use ra_db::{CrateId, Cancelable, FileId};
+use ra_syntax::{ast, SyntaxNode};
 
-use crate::{Name, db::HirDatabase, DefId, Path, PerNs, module::{ModuleSource, ModuleScope}};
+use crate::{Name, db::HirDatabase, DefId, Path, PerNs, module::{Problem, ModuleScope}};
 
 /// hir::Crate describes a single crate. It's the main inteface with which
 /// crate's dependencies interact. Mostly, it should be just a proxy for the
@@ -33,10 +34,27 @@ pub struct Module {
     pub(crate) def_id: DefId,
 }
 
+/// An owned syntax node for a module. Unlike `ModuleSource`,
+/// this holds onto the AST for the whole file.
+pub enum ModuleSource {
+    SourceFile(ast::SourceFileNode),
+    Module(ast::ModuleNode),
+}
+
 impl Module {
-    // FIXME: what is a module source exactly? It should contain two nodes
-    pub fn source(&self, db: &impl HirDatabase) -> Cancelable<ModuleSource> {
-        Ok(self.source_impl(db))
+    pub fn name(&self, db: &impl HirDatabase) -> Cancelable<Option<Name>> {
+        self.name_impl(db)
+    }
+
+    pub fn defenition_source(&self, db: &impl HirDatabase) -> Cancelable<(FileId, ModuleSource)> {
+        self.defenition_source_impl(db)
+    }
+
+    pub fn declaration_source(
+        &self,
+        db: &impl HirDatabase,
+    ) -> Cancelable<Option<(FileId, ast::ModuleNode)>> {
+        self.declaration_source_impl(db)
     }
 
     /// Returns the crate this module is part of.
@@ -56,6 +74,15 @@ impl Module {
     pub fn parent(&self, db: &impl HirDatabase) -> Cancelable<Option<Module>> {
         self.parent_impl(db)
     }
+    pub fn path_to_root(&self, db: &impl HirDatabase) -> Cancelable<Vec<Module>> {
+        let mut res = vec![self.clone()];
+        let mut curr = self.clone();
+        while let Some(next) = curr.parent(db)? {
+            res.push(next.clone());
+            curr = next
+        }
+        Ok(res)
+    }
     /// Returns a `ModuleScope`: a set of items, visible in this module.
     pub fn scope(&self, db: &impl HirDatabase) -> Cancelable<ModuleScope> {
         self.scope_impl(db)
@@ -63,4 +90,7 @@ impl Module {
     pub fn resolve_path(&self, db: &impl HirDatabase, path: &Path) -> Cancelable<PerNs<DefId>> {
         self.resolve_path_impl(db, path)
     }
+    pub fn problems(&self, db: &impl HirDatabase) -> Cancelable<Vec<(SyntaxNode, Problem)>> {
+        self.problems_impl(db)
+    }
 }
diff --git a/crates/ra_hir/src/code_model_impl.rs b/crates/ra_hir/src/code_model_impl.rs
index 7f5669c8f..4f4b506dd 100644
--- a/crates/ra_hir/src/code_model_impl.rs
+++ b/crates/ra_hir/src/code_model_impl.rs
@@ -1,12 +1,13 @@
-use ra_db::{CrateId, Cancelable, SourceRootId};
+use ra_db::{CrateId, Cancelable, SourceRootId, FileId};
+use ra_syntax::{ast, SyntaxNode, AstNode};
 
 use crate::{
     HirFileId, Crate, CrateDependency, AsName, DefId, DefLoc, DefKind, Name, Path, PathKind, PerNs, Def, ModuleId,
-    module::{ModuleSource, ModuleScope},
+    module::{ModuleScope, Problem},
     db::HirDatabase,
 };
 
-use crate::code_model_api::Module;
+use crate::code_model_api::{Module, ModuleSource};
 
 impl Crate {
     pub(crate) fn new(crate_id: CrateId) -> Crate {
@@ -68,9 +69,44 @@ impl Module {
         Ok(module)
     }
 
-    pub(crate) fn source_impl(&self, db: &impl HirDatabase) -> ModuleSource {
+    pub(crate) fn name_impl(&self, db: &impl HirDatabase) -> Cancelable<Option<Name>> {
         let loc = self.def_id.loc(db);
-        ModuleSource(loc.source_item_id)
+        let module_tree = db.module_tree(loc.source_root_id)?;
+        let link = ctry!(loc.module_id.parent_link(&module_tree));
+        Ok(Some(link.name(&module_tree).clone()))
+    }
+
+    pub fn defenition_source_impl(
+        &self,
+        db: &impl HirDatabase,
+    ) -> Cancelable<(FileId, ModuleSource)> {
+        let loc = self.def_id.loc(db);
+        let file_id = loc.source_item_id.file_id.as_original_file();
+        let syntax_node = db.file_item(loc.source_item_id);
+        let syntax_node = syntax_node.borrowed();
+        let module_source = if let Some(source_file) = ast::SourceFile::cast(syntax_node) {
+            ModuleSource::SourceFile(source_file.owned())
+        } else {
+            let module = ast::Module::cast(syntax_node).unwrap();
+            ModuleSource::Module(module.owned())
+        };
+        Ok((file_id, module_source))
+    }
+
+    pub fn declaration_source_impl(
+        &self,
+        db: &impl HirDatabase,
+    ) -> Cancelable<Option<(FileId, ast::ModuleNode)>> {
+        let loc = self.def_id.loc(db);
+        let module_tree = db.module_tree(loc.source_root_id)?;
+        let link = ctry!(loc.module_id.parent_link(&module_tree));
+        let file_id = link
+            .owner(&module_tree)
+            .source(&module_tree)
+            .file_id()
+            .as_original_file();
+        let src = link.bind_source(&module_tree, db);
+        Ok(Some((file_id, src)))
     }
 
     pub(crate) fn krate_impl(&self, db: &impl HirDatabase) -> Cancelable<Option<Crate>> {
@@ -150,4 +186,9 @@ impl Module {
         }
         Ok(curr_per_ns)
     }
+    pub fn problems_impl(&self, db: &impl HirDatabase) -> Cancelable<Vec<(SyntaxNode, Problem)>> {
+        let loc = self.def_id.loc(db);
+        let module_tree = db.module_tree(loc.source_root_id)?;
+        Ok(loc.module_id.problems(&module_tree, db))
+    }
 }
diff --git a/crates/ra_hir/src/impl_block.rs b/crates/ra_hir/src/impl_block.rs
index 891c93434..0d1b94c42 100644
--- a/crates/ra_hir/src/impl_block.rs
+++ b/crates/ra_hir/src/impl_block.rs
@@ -10,10 +10,10 @@ use crate::{
     Function,
     db::HirDatabase,
     type_ref::TypeRef,
-    module::{ModuleSourceNode, ModuleId},
+    module::ModuleId,
 };
 
-use crate::code_model_api::Module;
+use crate::code_model_api::{Module, ModuleSource};
 
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct ImplBlock {
@@ -150,13 +150,13 @@ impl ModuleImplBlocks {
     }
 
     fn collect(&mut self, db: &impl HirDatabase, module: Module) -> Cancelable<()> {
-        let module_source_node = module.source(db)?.resolve(db);
-        let node = match &module_source_node {
-            ModuleSourceNode::SourceFile(node) => node.borrowed().syntax(),
-            ModuleSourceNode::Module(node) => node.borrowed().syntax(),
+        let (file_id, module_source) = module.defenition_source(db)?;
+        let node = match &module_source {
+            ModuleSource::SourceFile(node) => node.borrowed().syntax(),
+            ModuleSource::Module(node) => node.borrowed().syntax(),
         };
 
-        let source_file_items = db.file_items(module.source(db)?.file_id());
+        let source_file_items = db.file_items(file_id.into());
 
         for impl_block_ast in node.children().filter_map(ast::ImplBlock::cast) {
             let impl_block = ImplData::from_ast(db, &source_file_items, &module, impl_block_ast);
diff --git a/crates/ra_hir/src/module.rs b/crates/ra_hir/src/module.rs
index d1005eab6..ebaf5f47a 100644
--- a/crates/ra_hir/src/module.rs
+++ b/crates/ra_hir/src/module.rs
@@ -1,8 +1,6 @@
 pub(super) mod imp;
 pub(super) mod nameres;
 
-use log;
-
 use ra_syntax::{
     algo::generate,
     ast::{self, AstNode, NameOwner},
@@ -11,10 +9,7 @@ use ra_syntax::{
 use ra_arena::{Arena, RawId, impl_arena_id};
 use relative_path::RelativePathBuf;
 
-use crate::{
-    Name,  HirDatabase, SourceItemId, SourceFileItemId,
-    HirFileId,
-};
+use crate::{Name, HirDatabase, SourceItemId, SourceFileItemId, HirFileId};
 
 pub use self::nameres::{ModuleScope, Resolution, Namespace, PerNs};
 
@@ -78,7 +73,7 @@ impl ModuleId {
     pub(crate) fn source(self, tree: &ModuleTree) -> ModuleSource {
         tree.mods[self].source
     }
-    fn parent_link(self, tree: &ModuleTree) -> Option<LinkId> {
+    pub(crate) fn parent_link(self, tree: &ModuleTree) -> Option<LinkId> {
         tree.mods[self].parent
     }
     pub(crate) fn parent(self, tree: &ModuleTree) -> Option<ModuleId> {
@@ -105,7 +100,11 @@ impl ModuleId {
             Some((link.name.clone(), module))
         })
     }
-    fn problems(self, tree: &ModuleTree, db: &impl HirDatabase) -> Vec<(SyntaxNode, Problem)> {
+    pub(crate) fn problems(
+        self,
+        tree: &ModuleTree,
+        db: &impl HirDatabase,
+    ) -> Vec<(SyntaxNode, Problem)> {
         tree.mods[self]
             .children
             .iter()
@@ -120,13 +119,17 @@ impl ModuleId {
 }
 
 impl LinkId {
-    fn owner(self, tree: &ModuleTree) -> ModuleId {
+    pub(crate) fn owner(self, tree: &ModuleTree) -> ModuleId {
         tree.links[self].owner
     }
-    fn name(self, tree: &ModuleTree) -> &Name {
+    pub(crate) fn name(self, tree: &ModuleTree) -> &Name {
         &tree.links[self].name
     }
-    fn bind_source<'a>(self, tree: &ModuleTree, db: &impl HirDatabase) -> ast::ModuleNode {
+    pub(crate) fn bind_source<'a>(
+        self,
+        tree: &ModuleTree,
+        db: &impl HirDatabase,
+    ) -> ast::ModuleNode {
         let owner = self.owner(tree);
         match owner.source(tree).resolve(db) {
             ModuleSourceNode::SourceFile(root) => {