79 files changed, 2024 insertions, 1618 deletions

diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 8ab47106d..974d18584 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -8,6 +8,16 @@ on:
       - trying
 
 jobs:
+  rust-audit:
+    name: Audit Rust vulnerabilities
+    runs-on: ubuntu-latest
+    steps:
+        - name: Checkout repository
+          uses: actions/checkout@v1
+
+        - run: cargo install cargo-audit
+        - run: cargo audit
+
   rust:
     name: Rust
     runs-on: ${{ matrix.os }}
@@ -79,7 +89,7 @@ jobs:
         if: matrix.os == 'windows-latest'
         run: Remove-Item ./target/debug/xtask.exe
 
-  type-script:
+  typescript:
     name: TypeScript
     runs-on: ubuntu-latest
     env:
@@ -96,7 +106,12 @@ jobs:
 
       - run: npm ci
         working-directory: ./editors/code
+
+      - run: npm audit
+        working-directory: ./editors/code
+
       - run: npm run fmt
         working-directory: ./editors/code
+
       - run: npm run package --scripts-prepend-node-path
         working-directory: ./editors/code
diff --git a/Cargo.lock b/Cargo.lock
index e5400f5eb..49fddef4b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -662,9 +662,9 @@ dependencies = [
 
 [[package]]
 name = "lsp-types"
-version = "0.70.2"
+version = "0.71.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6743fb3902ab3dfa6ce030daeac6ff492e20bb0fee840739d16f6bfb0efaf91c"
+checksum = "efa6b75633b0c3412ee36fc416e6d9c1e4ff576b536217f4ac3f34ac83d9e564"
 dependencies = [
  "base64",
  "bitflags",
@@ -882,9 +882,9 @@ dependencies = [
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.8"
+version = "1.0.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3acb317c6ff86a4e579dfa00fc5e6cca91ecbb4e7eb2df0468805b674eb88548"
+checksum = "6c09721c6781493a2a492a96b5a5bf19b65917fe6728884e7c44dd0c60ca3435"
 dependencies = [
  "unicode-xid",
 ]
@@ -906,7 +906,6 @@ version = "0.1.0"
 name = "ra_assists"
 version = "0.1.0"
 dependencies = [
- "either",
  "format-buf",
  "join_to_string",
  "ra_db",
@@ -927,10 +926,8 @@ dependencies = [
  "cargo_metadata",
  "crossbeam-channel",
  "insta",
- "jod-thread",
  "log",
  "lsp-types",
- "parking_lot",
  "serde_json",
 ]
 
@@ -988,7 +985,6 @@ dependencies = [
  "drop_bomb",
  "either",
  "insta",
- "itertools",
  "log",
  "once_cell",
  "ra_arena",
@@ -1046,7 +1042,6 @@ version = "0.1.0"
 dependencies = [
  "either",
  "format-buf",
- "fst",
  "indexmap",
  "insta",
  "itertools",
@@ -1063,29 +1058,17 @@ dependencies = [
  "ra_syntax",
  "ra_text_edit",
  "rand",
- "rayon",
  "rustc-hash",
- "superslice",
  "test_utils",
- "unicase",
 ]
 
 [[package]]
 name = "ra_ide_db"
 version = "0.1.0"
 dependencies = [
- "either",
- "format-buf",
  "fst",
- "indexmap",
- "insta",
- "itertools",
- "join_to_string",
  "log",
- "once_cell",
- "ra_cfg",
  "ra_db",
- "ra_fmt",
  "ra_hir",
  "ra_prof",
  "ra_syntax",
@@ -1093,8 +1076,6 @@ dependencies = [
  "rayon",
  "rustc-hash",
  "superslice",
- "test_utils",
- "unicase",
 ]
 
 [[package]]
@@ -1122,7 +1103,6 @@ name = "ra_prof"
 version = "0.1.0"
 dependencies = [
  "backtrace",
- "itertools",
  "jemalloc-ctl",
  "jemallocator",
  "once_cell",
@@ -1165,7 +1145,6 @@ dependencies = [
 name = "ra_text_edit"
 version = "0.1.0"
 dependencies = [
- "test_utils",
  "text_unit",
 ]
 
@@ -1324,7 +1303,6 @@ version = "0.1.0"
 dependencies = [
  "anyhow",
  "crossbeam-channel",
- "either",
  "env_logger",
  "globset",
  "itertools",
@@ -1534,9 +1512,9 @@ checksum = "ab16ced94dbd8a46c82fd81e3ed9a8727dac2977ea869d217bcc4ea1f122e81f"
 
 [[package]]
 name = "syn"
-version = "1.0.15"
+version = "1.0.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7a0294dc449adc58bb6592fff1a23d3e5e6e235afc6a0ffca2657d19e7bbffe5"
+checksum = "123bd9499cfb380418d509322d7a6d52e5315f064fe4b3ad18a53d6b92c07859"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -1577,9 +1555,9 @@ dependencies = [
 
 [[package]]
 name = "text_unit"
-version = "0.1.9"
+version = "0.1.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e08bbcb7a3adbda0eb23431206b653bdad3d8dea311e72d36bf2215e27a42579"
+checksum = "20431e104bfecc1a40872578dbc390e10290a0e9c35fffe3ce6f73c15a9dbfc2"
 
 [[package]]
 name = "thin-dst"
@@ -1606,15 +1584,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "unicase"
-version = "2.6.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "50f37be617794602aabbeee0be4f259dc1778fabe05e2d67ee8f79326d5cb4f6"
-dependencies = [
- "version_check",
-]
-
-[[package]]
 name = "unicode-bidi"
 version = "0.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1657,12 +1626,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "version_check"
-version = "0.9.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "078775d0255232fb988e6fccf26ddc9d1ac274299aaedcedce21c6f72cc533ce"
-
-[[package]]
 name = "walkdir"
 version = "2.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/crates/ra_assists/Cargo.toml b/crates/ra_assists/Cargo.toml
index 12a933645..d314dc8e6 100644
--- a/crates/ra_assists/Cargo.toml
+++ b/crates/ra_assists/Cargo.toml
@@ -11,7 +11,6 @@ doctest = false
 format-buf = "1.0.0"
 join_to_string = "0.1.3"
 rustc-hash = "1.1.0"
-either = "1.5.3"
 
 ra_syntax = { path = "../ra_syntax" }
 ra_text_edit = { path = "../ra_text_edit" }
diff --git a/crates/ra_assists/src/assist_ctx.rs b/crates/ra_assists/src/assist_ctx.rs
index 5aab5fb8b..c25d2e323 100644
--- a/crates/ra_assists/src/assist_ctx.rs
+++ b/crates/ra_assists/src/assist_ctx.rs
@@ -1,6 +1,6 @@
 //! This module defines `AssistCtx` -- the API surface that is exposed to assists.
-use hir::{InFile, SourceAnalyzer, SourceBinder};
-use ra_db::{FileRange, SourceDatabase};
+use hir::Semantics;
+use ra_db::FileRange;
 use ra_fmt::{leading_indent, reindent};
 use ra_ide_db::RootDatabase;
 use ra_syntax::{
@@ -74,29 +74,23 @@ pub(crate) type AssistHandler = fn(AssistCtx) -> Option<Assist>;
 /// Note, however, that we don't actually use such two-phase logic at the
 /// moment, because the LSP API is pretty awkward in this place, and it's much
 /// easier to just compute the edit eagerly :-)
-#[derive(Debug)]
+#[derive(Clone)]
 pub(crate) struct AssistCtx<'a> {
+    pub(crate) sema: &'a Semantics<'a, RootDatabase>,
     pub(crate) db: &'a RootDatabase,
     pub(crate) frange: FileRange,
     source_file: SourceFile,
     should_compute_edit: bool,
 }
 
-impl Clone for AssistCtx<'_> {
-    fn clone(&self) -> Self {
-        AssistCtx {
-            db: self.db,
-            frange: self.frange,
-            source_file: self.source_file.clone(),
-            should_compute_edit: self.should_compute_edit,
-        }
-    }
-}
-
 impl<'a> AssistCtx<'a> {
-    pub fn new(db: &RootDatabase, frange: FileRange, should_compute_edit: bool) -> AssistCtx {
-        let parse = db.parse(frange.file_id);
-        AssistCtx { db, frange, source_file: parse.tree(), should_compute_edit }
+    pub fn new(
+        sema: &'a Semantics<'a, RootDatabase>,
+        frange: FileRange,
+        should_compute_edit: bool,
+    ) -> AssistCtx<'a> {
+        let source_file = sema.parse(frange.file_id);
+        AssistCtx { sema, db: sema.db, frange, source_file, should_compute_edit }
     }
 
     pub(crate) fn add_assist(
@@ -138,18 +132,6 @@ impl<'a> AssistCtx<'a> {
     pub(crate) fn covering_element(&self) -> SyntaxElement {
         find_covering_element(self.source_file.syntax(), self.frange.range)
     }
-    pub(crate) fn source_binder(&self) -> SourceBinder<'a, RootDatabase> {
-        SourceBinder::new(self.db)
-    }
-    pub(crate) fn source_analyzer(
-        &self,
-        node: &SyntaxNode,
-        offset: Option<TextUnit>,
-    ) -> SourceAnalyzer {
-        let src = InFile::new(self.frange.file_id.into(), node);
-        self.source_binder().analyze(src, offset)
-    }
-
     pub(crate) fn covering_node_for_range(&self, range: TextRange) -> SyntaxElement {
         find_covering_element(self.source_file.syntax(), range)
     }
diff --git a/crates/ra_assists/src/ast_transform.rs b/crates/ra_assists/src/ast_transform.rs
index c6d15af5f..7846e9798 100644
--- a/crates/ra_assists/src/ast_transform.rs
+++ b/crates/ra_assists/src/ast_transform.rs
@@ -1,15 +1,12 @@
 //! `AstTransformer`s are functions that replace nodes in an AST and can be easily combined.
 use rustc_hash::FxHashMap;
 
-use hir::{InFile, PathResolution};
+use hir::{PathResolution, SemanticsScope};
 use ra_ide_db::RootDatabase;
 use ra_syntax::ast::{self, AstNode};
 
 pub trait AstTransform<'a> {
-    fn get_substitution(
-        &self,
-        node: InFile<&ra_syntax::SyntaxNode>,
-    ) -> Option<ra_syntax::SyntaxNode>;
+    fn get_substitution(&self, node: &ra_syntax::SyntaxNode) -> Option<ra_syntax::SyntaxNode>;
 
     fn chain_before(self, other: Box<dyn AstTransform<'a> + 'a>) -> Box<dyn AstTransform<'a> + 'a>;
     fn or<T: AstTransform<'a> + 'a>(self, other: T) -> Box<dyn AstTransform<'a> + 'a>
@@ -23,10 +20,7 @@ pub trait AstTransform<'a> {
 struct NullTransformer;
 
 impl<'a> AstTransform<'a> for NullTransformer {
-    fn get_substitution(
-        &self,
-        _node: InFile<&ra_syntax::SyntaxNode>,
-    ) -> Option<ra_syntax::SyntaxNode> {
+    fn get_substitution(&self, _node: &ra_syntax::SyntaxNode) -> Option<ra_syntax::SyntaxNode> {
         None
     }
     fn chain_before(self, other: Box<dyn AstTransform<'a> + 'a>) -> Box<dyn AstTransform<'a> + 'a> {
@@ -35,14 +29,16 @@ impl<'a> AstTransform<'a> for NullTransformer {
 }
 
 pub struct SubstituteTypeParams<'a> {
-    db: &'a RootDatabase,
+    source_scope: &'a SemanticsScope<'a, RootDatabase>,
     substs: FxHashMap<hir::TypeParam, ast::TypeRef>,
     previous: Box<dyn AstTransform<'a> + 'a>,
 }
 
 impl<'a> SubstituteTypeParams<'a> {
     pub fn for_trait_impl(
+        source_scope: &'a SemanticsScope<'a, RootDatabase>,
         db: &'a RootDatabase,
+        // FIXME: there's implicit invariant that `trait_` and  `source_scope` match...
         trait_: hir::Trait,
         impl_block: ast::ImplBlock,
     ) -> SubstituteTypeParams<'a> {
@@ -56,7 +52,7 @@ impl<'a> SubstituteTypeParams<'a> {
             .zip(substs.into_iter())
             .collect();
         return SubstituteTypeParams {
-            db,
+            source_scope,
             substs: substs_by_param,
             previous: Box::new(NullTransformer),
         };
@@ -80,15 +76,15 @@ impl<'a> SubstituteTypeParams<'a> {
     }
     fn get_substitution_inner(
         &self,
-        node: InFile<&ra_syntax::SyntaxNode>,
+        node: &ra_syntax::SyntaxNode,
     ) -> Option<ra_syntax::SyntaxNode> {
-        let type_ref = ast::TypeRef::cast(node.value.clone())?;
+        let type_ref = ast::TypeRef::cast(node.clone())?;
         let path = match &type_ref {
             ast::TypeRef::PathType(path_type) => path_type.path()?,
             _ => return None,
         };
-        let analyzer = hir::SourceAnalyzer::new(self.db, node, None);
-        let resolution = analyzer.resolve_path(self.db, &path)?;
+        let path = hir::Path::from_ast(path)?;
+        let resolution = self.source_scope.resolve_hir_path(&path)?;
         match resolution {
             hir::PathResolution::TypeParam(tp) => Some(self.substs.get(&tp)?.syntax().clone()),
             _ => None,
@@ -97,10 +93,7 @@ impl<'a> SubstituteTypeParams<'a> {
 }
 
 impl<'a> AstTransform<'a> for SubstituteTypeParams<'a> {
-    fn get_substitution(
-        &self,
-        node: InFile<&ra_syntax::SyntaxNode>,
-    ) -> Option<ra_syntax::SyntaxNode> {
+    fn get_substitution(&self, node: &ra_syntax::SyntaxNode) -> Option<ra_syntax::SyntaxNode> {
         self.get_substitution_inner(node).or_else(|| self.previous.get_substitution(node))
     }
     fn chain_before(self, other: Box<dyn AstTransform<'a> + 'a>) -> Box<dyn AstTransform<'a> + 'a> {
@@ -109,29 +102,34 @@ impl<'a> AstTransform<'a> for SubstituteTypeParams<'a> {
 }
 
 pub struct QualifyPaths<'a> {
+    target_scope: &'a SemanticsScope<'a, RootDatabase>,
+    source_scope: &'a SemanticsScope<'a, RootDatabase>,
     db: &'a RootDatabase,
-    from: Option<hir::Module>,
     previous: Box<dyn AstTransform<'a> + 'a>,
 }
 
 impl<'a> QualifyPaths<'a> {
-    pub fn new(db: &'a RootDatabase, from: Option<hir::Module>) -> Self {
-        Self { db, from, previous: Box::new(NullTransformer) }
+    pub fn new(
+        target_scope: &'a SemanticsScope<'a, RootDatabase>,
+        source_scope: &'a SemanticsScope<'a, RootDatabase>,
+        db: &'a RootDatabase,
+    ) -> Self {
+        Self { target_scope, source_scope, db, previous: Box::new(NullTransformer) }
     }
 
     fn get_substitution_inner(
         &self,
-        node: InFile<&ra_syntax::SyntaxNode>,
+        node: &ra_syntax::SyntaxNode,
     ) -> Option<ra_syntax::SyntaxNode> {
         // FIXME handle value ns?
-        let from = self.from?;
-        let p = ast::Path::cast(node.value.clone())?;
+        let from = self.target_scope.module()?;
+        let p = ast::Path::cast(node.clone())?;
         if p.segment().and_then(|s| s.param_list()).is_some() {
             // don't try to qualify `Fn(Foo) -> Bar` paths, they are in prelude anyway
             return None;
         }
-        let analyzer = hir::SourceAnalyzer::new(self.db, node, None);
-        let resolution = analyzer.resolve_path(self.db, &p)?;
+        let hir_path = hir::Path::from_ast(p.clone());
+        let resolution = self.source_scope.resolve_hir_path(&hir_path?)?;
         match resolution {
             PathResolution::Def(def) => {
                 let found_path = from.find_use_path(self.db, def)?;
@@ -140,7 +138,7 @@ impl<'a> QualifyPaths<'a> {
                 let type_args = p
                     .segment()
                     .and_then(|s| s.type_arg_list())
-                    .map(|arg_list| apply(self, node.with_value(arg_list)));
+                    .map(|arg_list| apply(self, arg_list));
                 if let Some(type_args) = type_args {
                     let last_segment = path.segment().unwrap();
                     path = path.with_segment(last_segment.with_type_args(type_args))
@@ -157,11 +155,11 @@ impl<'a> QualifyPaths<'a> {
     }
 }
 
-pub fn apply<'a, N: AstNode>(transformer: &dyn AstTransform<'a>, node: InFile<N>) -> N {
-    let syntax = node.value.syntax();
+pub fn apply<'a, N: AstNode>(transformer: &dyn AstTransform<'a>, node: N) -> N {
+    let syntax = node.syntax();
     let result = ra_syntax::algo::replace_descendants(syntax, &|element| match element {
         ra_syntax::SyntaxElement::Node(n) => {
-            let replacement = transformer.get_substitution(node.with_value(&n))?;
+            let replacement = transformer.get_substitution(&n)?;
             Some(replacement.into())
         }
         _ => None,
@@ -170,10 +168,7 @@ pub fn apply<'a, N: AstNode>(transformer: &dyn AstTransform<'a>, node: InFile<N>
 }
 
 impl<'a> AstTransform<'a> for QualifyPaths<'a> {
-    fn get_substitution(
-        &self,
-        node: InFile<&ra_syntax::SyntaxNode>,
-    ) -> Option<ra_syntax::SyntaxNode> {
+    fn get_substitution(&self, node: &ra_syntax::SyntaxNode) -> Option<ra_syntax::SyntaxNode> {
         self.get_substitution_inner(node).or_else(|| self.previous.get_substitution(node))
     }
     fn chain_before(self, other: Box<dyn AstTransform<'a> + 'a>) -> Box<dyn AstTransform<'a> + 'a> {
diff --git a/crates/ra_assists/src/handlers/add_explicit_type.rs b/crates/ra_assists/src/handlers/add_explicit_type.rs
index 2cb9d2f48..a63ef48b1 100644
--- a/crates/ra_assists/src/handlers/add_explicit_type.rs
+++ b/crates/ra_assists/src/handlers/add_explicit_type.rs
@@ -51,14 +51,13 @@ pub(crate) fn add_explicit_type(ctx: AssistCtx) -> Option<Assist> {
         }
     }
     // Infer type
-    let db = ctx.db;
-    let analyzer = ctx.source_analyzer(stmt.syntax(), None);
-    let ty = analyzer.type_of(db, &expr)?;
+    let ty = ctx.sema.type_of_expr(&expr)?;
     // Assist not applicable if the type is unknown
     if ty.contains_unknown() {
         return None;
     }
 
+    let db = ctx.db;
     ctx.add_assist(
         AssistId("add_explicit_type"),
         format!("Insert explicit type '{}'", ty.display(db)),
diff --git a/crates/ra_assists/src/handlers/add_missing_impl_members.rs b/crates/ra_assists/src/handlers/add_missing_impl_members.rs
index ab21388c8..4005014bd 100644
--- a/crates/ra_assists/src/handlers/add_missing_impl_members.rs
+++ b/crates/ra_assists/src/handlers/add_missing_impl_members.rs
@@ -1,4 +1,4 @@
-use hir::{HasSource, InFile};
+use hir::HasSource;
 use ra_syntax::{
     ast::{self, edit, make, AstNode, NameOwner},
     SmolStr,
@@ -104,9 +104,7 @@ fn add_missing_impl_members_inner(
     let impl_node = ctx.find_node_at_offset::<ast::ImplBlock>()?;
     let impl_item_list = impl_node.item_list()?;
 
-    let analyzer = ctx.source_analyzer(impl_node.syntax(), None);
-
-    let trait_ = resolve_target_trait(ctx.db, &analyzer, &impl_node)?;
+    let trait_ = resolve_target_trait(&ctx.sema, &impl_node)?;
 
     let def_name = |item: &ast::ImplItem| -> Option<SmolStr> {
         match item {
@@ -117,7 +115,7 @@ fn add_missing_impl_members_inner(
         .map(|it| it.text().clone())
     };
 
-    let missing_items = get_missing_impl_items(ctx.db, &analyzer, &impl_node)
+    let missing_items = get_missing_impl_items(&ctx.sema, &impl_node)
         .iter()
         .map(|i| match i {
             hir::AssocItem::Function(i) => ast::ImplItem::FnDef(i.source(ctx.db).value),
@@ -138,23 +136,17 @@ fn add_missing_impl_members_inner(
         return None;
     }
 
-    let db = ctx.db;
-    let file_id = ctx.frange.file_id;
-    let trait_file_id = trait_.source(db).file_id;
+    let sema = ctx.sema;
 
     ctx.add_assist(AssistId(assist_id), label, |edit| {
         let n_existing_items = impl_item_list.impl_items().count();
-        let module = hir::SourceAnalyzer::new(
-            db,
-            hir::InFile::new(file_id.into(), impl_node.syntax()),
-            None,
-        )
-        .module();
-        let ast_transform = QualifyPaths::new(db, module)
-            .or(SubstituteTypeParams::for_trait_impl(db, trait_, impl_node));
+        let source_scope = sema.scope_for_def(trait_);
+        let target_scope = sema.scope(impl_item_list.syntax());
+        let ast_transform = QualifyPaths::new(&target_scope, &source_scope, sema.db)
+            .or(SubstituteTypeParams::for_trait_impl(&source_scope, sema.db, trait_, impl_node));
         let items = missing_items
             .into_iter()
-            .map(|it| ast_transform::apply(&*ast_transform, InFile::new(trait_file_id, it)))
+            .map(|it| ast_transform::apply(&*ast_transform, it))
             .map(|it| match it {
                 ast::ImplItem::FnDef(def) => ast::ImplItem::FnDef(add_body(def)),
                 _ => it,
@@ -181,9 +173,10 @@ fn add_body(fn_def: ast::FnDef) -> ast::FnDef {
 
 #[cfg(test)]
 mod tests {
-    use super::*;
     use crate::helpers::{check_assist, check_assist_not_applicable};
 
+    use super::*;
+
     #[test]
     fn test_add_missing_impl_members() {
         check_assist(
diff --git a/crates/ra_assists/src/handlers/add_new.rs b/crates/ra_assists/src/handlers/add_new.rs
index dd070e8ec..166e907fb 100644
--- a/crates/ra_assists/src/handlers/add_new.rs
+++ b/crates/ra_assists/src/handlers/add_new.rs
@@ -1,5 +1,5 @@
 use format_buf::format;
-use hir::{Adt, InFile};
+use hir::Adt;
 use join_to_string::join;
 use ra_syntax::{
     ast::{
@@ -133,16 +133,11 @@ fn find_struct_impl(ctx: &AssistCtx, strukt: &ast::StructDef) -> Option<Option<a
     let module = strukt.syntax().ancestors().find(|node| {
         ast::Module::can_cast(node.kind()) || ast::SourceFile::can_cast(node.kind())
     })?;
-    let mut sb = ctx.source_binder();
 
-    let struct_def = {
-        let src = InFile { file_id: ctx.frange.file_id.into(), value: strukt.clone() };
-        sb.to_def(src)?
-    };
+    let struct_def = ctx.sema.to_def(strukt)?;
 
     let block = module.descendants().filter_map(ast::ImplBlock::cast).find_map(|impl_blk| {
-        let src = InFile { file_id: ctx.frange.file_id.into(), value: impl_blk.clone() };
-        let blk = sb.to_def(src)?;
+        let blk = ctx.sema.to_def(&impl_blk)?;
 
         // FIXME: handle e.g. `struct S<T>; impl<U> S<U> {}`
         // (we currently use the wrong type parameter)
diff --git a/crates/ra_assists/src/handlers/auto_import.rs b/crates/ra_assists/src/handlers/auto_import.rs
index c4aea2a06..edf0cf6d0 100644
--- a/crates/ra_assists/src/handlers/auto_import.rs
+++ b/crates/ra_assists/src/handlers/auto_import.rs
@@ -3,8 +3,8 @@ use crate::{
     insert_use_statement, AssistId,
 };
 use hir::{
-    db::HirDatabase, AsAssocItem, AssocItemContainer, ModPath, Module, ModuleDef, PathResolution,
-    SourceAnalyzer, Trait, Type,
+    AsAssocItem, AssocItemContainer, ModPath, Module, ModuleDef, PathResolution, Semantics, Trait,
+    Type,
 };
 use ra_ide_db::{imports_locator::ImportsLocator, RootDatabase};
 use ra_prof::profile;
@@ -78,14 +78,9 @@ impl AutoImportAssets {
 
     fn for_method_call(method_call: ast::MethodCallExpr, ctx: &AssistCtx) -> Option<Self> {
         let syntax_under_caret = method_call.syntax().to_owned();
-        let source_analyzer = ctx.source_analyzer(&syntax_under_caret, None);
-        let module_with_name_to_import = source_analyzer.module()?;
+        let module_with_name_to_import = ctx.sema.scope(&syntax_under_caret).module()?;
         Some(Self {
-            import_candidate: ImportCandidate::for_method_call(
-                &method_call,
-                &source_analyzer,
-                ctx.db,
-            )?,
+            import_candidate: ImportCandidate::for_method_call(&ctx.sema, &method_call)?,
             module_with_name_to_import,
             syntax_under_caret,
         })
@@ -97,14 +92,9 @@ impl AutoImportAssets {
             return None;
         }
 
-        let source_analyzer = ctx.source_analyzer(&syntax_under_caret, None);
-        let module_with_name_to_import = source_analyzer.module()?;
+        let module_with_name_to_import = ctx.sema.scope(&syntax_under_caret).module()?;
         Some(Self {
-            import_candidate: ImportCandidate::for_regular_path(
-                &path_under_caret,
-                &source_analyzer,
-                ctx.db,
-            )?,
+            import_candidate: ImportCandidate::for_regular_path(&ctx.sema, &path_under_caret)?,
             module_with_name_to_import,
             syntax_under_caret,
         })
@@ -229,25 +219,23 @@ enum ImportCandidate {
 
 impl ImportCandidate {
     fn for_method_call(
+        sema: &Semantics<RootDatabase>,
         method_call: &ast::MethodCallExpr,
-        source_analyzer: &SourceAnalyzer,
-        db: &impl HirDatabase,
     ) -> Option<Self> {
-        if source_analyzer.resolve_method_call(method_call).is_some() {
+        if sema.resolve_method_call(method_call).is_some() {
             return None;
         }
         Some(Self::TraitMethod(
-            source_analyzer.type_of(db, &method_call.expr()?)?,
+            sema.type_of_expr(&method_call.expr()?)?,
             method_call.name_ref()?.syntax().to_string(),
         ))
     }
 
     fn for_regular_path(
+        sema: &Semantics<RootDatabase>,
         path_under_caret: &ast::Path,
-        source_analyzer: &SourceAnalyzer,
-        db: &impl HirDatabase,
     ) -> Option<Self> {
-        if source_analyzer.resolve_path(db, path_under_caret).is_some() {
+        if sema.resolve_path(path_under_caret).is_some() {
             return None;
         }
 
@@ -256,17 +244,15 @@ impl ImportCandidate {
             let qualifier_start = qualifier.syntax().descendants().find_map(ast::NameRef::cast)?;
             let qualifier_start_path =
                 qualifier_start.syntax().ancestors().find_map(ast::Path::cast)?;
-            if let Some(qualifier_start_resolution) =
-                source_analyzer.resolve_path(db, &qualifier_start_path)
-            {
+            if let Some(qualifier_start_resolution) = sema.resolve_path(&qualifier_start_path) {
                 let qualifier_resolution = if qualifier_start_path == qualifier {
                     qualifier_start_resolution
                 } else {
-                    source_analyzer.resolve_path(db, &qualifier)?
+                    sema.resolve_path(&qualifier)?
                 };
                 if let PathResolution::Def(ModuleDef::Adt(assoc_item_path)) = qualifier_resolution {
                     Some(ImportCandidate::TraitAssocItem(
-                        assoc_item_path.ty(db),
+                        assoc_item_path.ty(sema.db),
                         segment.syntax().to_string(),
                     ))
                 } else {
diff --git a/crates/ra_assists/src/handlers/fill_match_arms.rs b/crates/ra_assists/src/handlers/fill_match_arms.rs
index ae2437ed3..e5d8c639d 100644
--- a/crates/ra_assists/src/handlers/fill_match_arms.rs
+++ b/crates/ra_assists/src/handlers/fill_match_arms.rs
@@ -2,10 +2,11 @@
 
 use std::iter;
 
-use hir::{db::HirDatabase, Adt, HasSource};
+use hir::{db::HirDatabase, Adt, HasSource, Semantics};
 use ra_syntax::ast::{self, edit::IndentLevel, make, AstNode, NameOwner};
 
 use crate::{Assist, AssistCtx, AssistId};
+use ra_ide_db::RootDatabase;
 
 // Assist: fill_match_arms
 //
@@ -46,10 +47,9 @@ pub(crate) fn fill_match_arms(ctx: AssistCtx) -> Option<Assist> {
     };
 
     let expr = match_expr.expr()?;
-    let (enum_def, module) = {
-        let analyzer = ctx.source_analyzer(expr.syntax(), None);
-        (resolve_enum_def(ctx.db, &analyzer, &expr)?, analyzer.module()?)
-    };
+    let enum_def = resolve_enum_def(&ctx.sema, &expr)?;
+    let module = ctx.sema.scope(expr.syntax()).module()?;
+
     let variants = enum_def.variants(ctx.db);
     if variants.is_empty() {
         return None;
@@ -81,18 +81,11 @@ fn is_trivial(arm: &ast::MatchArm) -> bool {
     }
 }
 
-fn resolve_enum_def(
-    db: &impl HirDatabase,
-    analyzer: &hir::SourceAnalyzer,
-    expr: &ast::Expr,
-) -> Option<hir::Enum> {
-    let expr_ty = analyzer.type_of(db, &expr)?;
-
-    let result = expr_ty.autoderef(db).find_map(|ty| match ty.as_adt() {
+fn resolve_enum_def(sema: &Semantics<RootDatabase>, expr: &ast::Expr) -> Option<hir::Enum> {
+    sema.type_of_expr(&expr)?.autoderef(sema.db).find_map(|ty| match ty.as_adt() {
         Some(Adt::Enum(e)) => Some(e),
         _ => None,
-    });
-    result
+    })
 }
 
 fn build_pat(
diff --git a/crates/ra_assists/src/handlers/inline_local_variable.rs b/crates/ra_assists/src/handlers/inline_local_variable.rs
index 91b588243..53a72309b 100644
--- a/crates/ra_assists/src/handlers/inline_local_variable.rs
+++ b/crates/ra_assists/src/handlers/inline_local_variable.rs
@@ -44,8 +44,7 @@ pub(crate) fn inline_local_variable(ctx: AssistCtx) -> Option<Assist> {
     } else {
         let_stmt.syntax().text_range()
     };
-    let analyzer = ctx.source_analyzer(bind_pat.syntax(), None);
-    let refs = analyzer.find_all_refs(&bind_pat);
+    let refs = ctx.sema.find_all_refs(&bind_pat);
     if refs.is_empty() {
         return None;
     };
diff --git a/crates/ra_assists/src/handlers/introduce_variable.rs b/crates/ra_assists/src/handlers/introduce_variable.rs
index 7312ce687..b453c51fb 100644
--- a/crates/ra_assists/src/handlers/introduce_variable.rs
+++ b/crates/ra_assists/src/handlers/introduce_variable.rs
@@ -136,15 +136,13 @@ fn anchor_stmt(expr: ast::Expr) -> Option<(SyntaxNode, bool)> {
 mod tests {
     use test_utils::covers;
 
-    use crate::helpers::{
-        check_assist_range, check_assist_range_not_applicable, check_assist_range_target,
-    };
+    use crate::helpers::{check_assist, check_assist_not_applicable, check_assist_target};
 
     use super::*;
 
     #[test]
     fn test_introduce_var_simple() {
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn foo() {
@@ -161,16 +159,13 @@ fn foo() {
     #[test]
     fn introduce_var_in_comment_is_not_applicable() {
         covers!(introduce_var_in_comment_is_not_applicable);
-        check_assist_range_not_applicable(
-            introduce_variable,
-            "fn main() { 1 + /* <|>comment<|> */ 1; }",
-        );
+        check_assist_not_applicable(introduce_variable, "fn main() { 1 + /* <|>comment<|> */ 1; }");
     }
 
     #[test]
     fn test_introduce_var_expr_stmt() {
         covers!(test_introduce_var_expr_stmt);
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn foo() {
@@ -181,7 +176,7 @@ fn foo() {
     let <|>var_name = 1 + 1;
 }",
         );
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn foo() {
@@ -198,7 +193,7 @@ fn foo() {
 
     #[test]
     fn test_introduce_var_part_of_expr_stmt() {
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn foo() {
@@ -215,7 +210,7 @@ fn foo() {
     #[test]
     fn test_introduce_var_last_expr() {
         covers!(test_introduce_var_last_expr);
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn foo() {
@@ -227,7 +222,7 @@ fn foo() {
     bar(var_name)
 }",
         );
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn foo() {
@@ -243,7 +238,7 @@ fn foo() {
 
     #[test]
     fn test_introduce_var_in_match_arm_no_block() {
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn main() {
@@ -268,7 +263,7 @@ fn main() {
 
     #[test]
     fn test_introduce_var_in_match_arm_with_block() {
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn main() {
@@ -300,7 +295,7 @@ fn main() {
 
     #[test]
     fn test_introduce_var_in_closure_no_block() {
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn main() {
@@ -317,7 +312,7 @@ fn main() {
 
     #[test]
     fn test_introduce_var_in_closure_with_block() {
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn main() {
@@ -334,7 +329,7 @@ fn main() {
 
     #[test]
     fn test_introduce_var_path_simple() {
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn main() {
@@ -352,7 +347,7 @@ fn main() {
 
     #[test]
     fn test_introduce_var_path_method() {
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn main() {
@@ -370,7 +365,7 @@ fn main() {
 
     #[test]
     fn test_introduce_var_return() {
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn foo() -> u32 {
@@ -388,7 +383,7 @@ fn foo() -> u32 {
 
     #[test]
     fn test_introduce_var_does_not_add_extra_whitespace() {
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn foo() -> u32 {
@@ -407,7 +402,7 @@ fn foo() -> u32 {
 ",
         );
 
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn foo() -> u32 {
@@ -424,7 +419,7 @@ fn foo() -> u32 {
 ",
         );
 
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn foo() -> u32 {
@@ -452,7 +447,7 @@ fn foo() -> u32 {
 
     #[test]
     fn test_introduce_var_break() {
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn main() {
@@ -474,7 +469,7 @@ fn main() {
 
     #[test]
     fn test_introduce_var_for_cast() {
-        check_assist_range(
+        check_assist(
             introduce_variable,
             "
 fn main() {
@@ -492,27 +487,20 @@ fn main() {
 
     #[test]
     fn test_introduce_var_for_return_not_applicable() {
-        check_assist_range_not_applicable(introduce_variable, "fn foo() { <|>return<|>; } ");
+        check_assist_not_applicable(introduce_variable, "fn foo() { <|>return<|>; } ");
     }
 
     #[test]
     fn test_introduce_var_for_break_not_applicable() {
-        check_assist_range_not_applicable(
-            introduce_variable,
-            "fn main() { loop { <|>break<|>; }; }",
-        );
+        check_assist_not_applicable(introduce_variable, "fn main() { loop { <|>break<|>; }; }");
     }
 
     // FIXME: This is not quite correct, but good enough(tm) for the sorting heuristic
     #[test]
     fn introduce_var_target() {
-        check_assist_range_target(
-            introduce_variable,
-            "fn foo() -> u32 { <|>return 2 + 2<|>; }",
-            "2 + 2",
-        );
+        check_assist_target(introduce_variable, "fn foo() -> u32 { <|>return 2 + 2<|>; }", "2 + 2");
 
-        check_assist_range_target(
+        check_assist_target(
             introduce_variable,
             "
 fn main() {
diff --git a/crates/ra_assists/src/lib.rs b/crates/ra_assists/src/lib.rs
index d7998b0d1..c28a9b92b 100644
--- a/crates/ra_assists/src/lib.rs
+++ b/crates/ra_assists/src/lib.rs
@@ -19,6 +19,7 @@ use ra_text_edit::TextEdit;
 
 pub(crate) use crate::assist_ctx::{Assist, AssistCtx, AssistHandler};
 pub use crate::handlers::replace_qualified_name_with_use::insert_use_statement;
+use hir::Semantics;
 
 /// Unique identifier of the assist, should not be shown to the user
 /// directly.
@@ -63,7 +64,8 @@ pub struct ResolvedAssist {
 /// Assists are returned in the "unresolved" state, that is only labels are
 /// returned, without actual edits.
 pub fn unresolved_assists(db: &RootDatabase, range: FileRange) -> Vec<AssistLabel> {
-    let ctx = AssistCtx::new(db, range, false);
+    let sema = Semantics::new(db);
+    let ctx = AssistCtx::new(&sema, range, false);
     handlers::all()
         .iter()
         .filter_map(|f| f(ctx.clone()))
@@ -77,7 +79,8 @@ pub fn unresolved_assists(db: &RootDatabase, range: FileRange) -> Vec<AssistLabe
 /// Assists are returned in the "resolved" state, that is with edit fully
 /// computed.
 pub fn resolved_assists(db: &RootDatabase, range: FileRange) -> Vec<ResolvedAssist> {
-    let ctx = AssistCtx::new(db, range, true);
+    let sema = Semantics::new(db);
+    let ctx = AssistCtx::new(&sema, range, true);
     let mut a = handlers::all()
         .iter()
         .filter_map(|f| f(ctx.clone()))
@@ -162,9 +165,10 @@ mod helpers {
     use ra_db::{fixture::WithFixture, FileId, FileRange, SourceDatabaseExt};
     use ra_ide_db::{symbol_index::SymbolsDatabase, RootDatabase};
     use ra_syntax::TextRange;
-    use test_utils::{add_cursor, assert_eq_text, extract_offset, extract_range};
+    use test_utils::{add_cursor, assert_eq_text, extract_range_or_offset, RangeOrOffset};
 
     use crate::{AssistCtx, AssistHandler};
+    use hir::Semantics;
 
     pub(crate) fn with_single_file(text: &str) -> (RootDatabase, FileId) {
         let (mut db, file_id) = RootDatabase::with_single_file(text);
@@ -176,81 +180,66 @@ mod helpers {
     }
 
     pub(crate) fn check_assist(assist: AssistHandler, before: &str, after: &str) {
-        let (before_cursor_pos, before) = extract_offset(before);
-        let (db, file_id) = with_single_file(&before);
-        let frange =
-            FileRange { file_id, range: TextRange::offset_len(before_cursor_pos, 0.into()) };
-        let assist =
-            assist(AssistCtx::new(&db, frange, true)).expect("code action is not applicable");
-        let action = assist.0[0].action.clone().unwrap();
-
-        let actual = action.edit.apply(&before);
-        let actual_cursor_pos = match action.cursor_position {
-            None => action
-                .edit
-                .apply_to_offset(before_cursor_pos)
-                .expect("cursor position is affected by the edit"),
-            Some(off) => off,
-        };
-        let actual = add_cursor(&actual, actual_cursor_pos);
-        assert_eq_text!(after, &actual);
-    }
-
-    pub(crate) fn check_assist_range(assist: AssistHandler, before: &str, after: &str) {
-        let (range, before) = extract_range(before);
-        let (db, file_id) = with_single_file(&before);
-        let frange = FileRange { file_id, range };
-        let assist =
-            assist(AssistCtx::new(&db, frange, true)).expect("code action is not applicable");
-        let action = assist.0[0].action.clone().unwrap();
-
-        let mut actual = action.edit.apply(&before);
-        if let Some(pos) = action.cursor_position {
-            actual = add_cursor(&actual, pos);
-        }
-        assert_eq_text!(after, &actual);
+        check(assist, before, ExpectedResult::After(after));
     }
 
+    // FIXME: instead of having a separate function here, maybe use
+    // `extract_ranges` and mark the target as `<target> </target>` in the
+    // fixuture?
     pub(crate) fn check_assist_target(assist: AssistHandler, before: &str, target: &str) {
-        let (before_cursor_pos, before) = extract_offset(before);
-        let (db, file_id) = with_single_file(&before);
-        let frange =
-            FileRange { file_id, range: TextRange::offset_len(before_cursor_pos, 0.into()) };
-        let assist =
-            assist(AssistCtx::new(&db, frange, true)).expect("code action is not applicable");
-        let action = assist.0[0].action.clone().unwrap();
-
-        let range = action.target.expect("expected target on action");
-        assert_eq_text!(&before[range.start().to_usize()..range.end().to_usize()], target);
+        check(assist, before, ExpectedResult::Target(target));
     }
 
-    pub(crate) fn check_assist_range_target(assist: AssistHandler, before: &str, target: &str) {
-        let (range, before) = extract_range(before);
-        let (db, file_id) = with_single_file(&before);
-        let frange = FileRange { file_id, range };
-        let assist =
-            assist(AssistCtx::new(&db, frange, true)).expect("code action is not applicable");
-        let action = assist.0[0].action.clone().unwrap();
-
-        let range = action.target.expect("expected target on action");
-        assert_eq_text!(&before[range.start().to_usize()..range.end().to_usize()], target);
+    pub(crate) fn check_assist_not_applicable(assist: AssistHandler, before: &str) {
+        check(assist, before, ExpectedResult::NotApplicable);
     }
 
-    pub(crate) fn check_assist_not_applicable(assist: AssistHandler, before: &str) {
-        let (before_cursor_pos, before) = extract_offset(before);
-        let (db, file_id) = with_single_file(&before);
-        let frange =
-            FileRange { file_id, range: TextRange::offset_len(before_cursor_pos, 0.into()) };
-        let assist = assist(AssistCtx::new(&db, frange, true));
-        assert!(assist.is_none());
+    enum ExpectedResult<'a> {
+        NotApplicable,
+        After(&'a str),
+        Target(&'a str),
     }
 
-    pub(crate) fn check_assist_range_not_applicable(assist: AssistHandler, before: &str) {
-        let (range, before) = extract_range(before);
+    fn check(assist: AssistHandler, before: &str, expected: ExpectedResult) {
+        let (range_or_offset, before) = extract_range_or_offset(before);
+        let range: TextRange = range_or_offset.into();
+
         let (db, file_id) = with_single_file(&before);
         let frange = FileRange { file_id, range };
-        let assist = assist(AssistCtx::new(&db, frange, true));
-        assert!(assist.is_none());
+        let sema = Semantics::new(&db);
+        let assist_ctx = AssistCtx::new(&sema, frange, true);
+
+        match (assist(assist_ctx), expected) {
+            (Some(assist), ExpectedResult::After(after)) => {
+                let action = assist.0[0].action.clone().unwrap();
+
+                let mut actual = action.edit.apply(&before);
+                match action.cursor_position {
+                    None => {
+                        if let RangeOrOffset::Offset(before_cursor_pos) = range_or_offset {
+                            let off = action
+                                .edit
+                                .apply_to_offset(before_cursor_pos)
+                                .expect("cursor position is affected by the edit");
+                            actual = add_cursor(&actual, off)
+                        }
+                    }
+                    Some(off) => actual = add_cursor(&actual, off),
+                };
+
+                assert_eq_text!(after, &actual);
+            }
+            (Some(assist), ExpectedResult::Target(target)) => {
+                let action = assist.0[0].action.clone().unwrap();
+                let range = action.target.expect("expected target on action");
+                assert_eq_text!(&before[range.start().to_usize()..range.end().to_usize()], target);
+            }
+            (Some(_), ExpectedResult::NotApplicable) => panic!("assist should not be applicable!"),
+            (None, ExpectedResult::After(_)) | (None, ExpectedResult::Target(_)) => {
+                panic!("code action is not applicable")
+            }
+            (None, ExpectedResult::NotApplicable) => (),
+        };
     }
 }
 
diff --git a/crates/ra_assists/src/utils.rs b/crates/ra_assists/src/utils.rs
index 6ff44c95c..92d3ed471 100644
--- a/crates/ra_assists/src/utils.rs
+++ b/crates/ra_assists/src/utils.rs
@@ -1,16 +1,15 @@
 //! Assorted functions shared by several assists.
 
+use hir::Semantics;
+use ra_ide_db::RootDatabase;
 use ra_syntax::{
     ast::{self, make, NameOwner},
     AstNode, T,
 };
-
-use hir::db::HirDatabase;
 use rustc_hash::FxHashSet;
 
 pub fn get_missing_impl_items(
-    db: &impl HirDatabase,
-    analyzer: &hir::SourceAnalyzer,
+    sema: &Semantics<RootDatabase>,
     impl_block: &ast::ImplBlock,
 ) -> Vec<hir::AssocItem> {
     // Names must be unique between constants and functions. However, type aliases
@@ -42,15 +41,17 @@ pub fn get_missing_impl_items(
         }
     }
 
-    resolve_target_trait(db, analyzer, impl_block).map_or(vec![], |target_trait| {
+    resolve_target_trait(sema, impl_block).map_or(vec![], |target_trait| {
         target_trait
-            .items(db)
+            .items(sema.db)
             .iter()
             .filter(|i| match i {
-                hir::AssocItem::Function(f) => !impl_fns_consts.contains(&f.name(db).to_string()),
-                hir::AssocItem::TypeAlias(t) => !impl_type.contains(&t.name(db).to_string()),
+                hir::AssocItem::Function(f) => {
+                    !impl_fns_consts.contains(&f.name(sema.db).to_string())
+                }
+                hir::AssocItem::TypeAlias(t) => !impl_type.contains(&t.name(sema.db).to_string()),
                 hir::AssocItem::Const(c) => c
-                    .name(db)
+                    .name(sema.db)
                     .map(|n| !impl_fns_consts.contains(&n.to_string()))
                     .unwrap_or_default(),
             })
@@ -60,8 +61,7 @@ pub fn get_missing_impl_items(
 }
 
 pub(crate) fn resolve_target_trait(
-    db: &impl HirDatabase,
-    analyzer: &hir::SourceAnalyzer,
+    sema: &Semantics<RootDatabase>,
     impl_block: &ast::ImplBlock,
 ) -> Option<hir::Trait> {
     let ast_path = impl_block
@@ -70,7 +70,7 @@ pub(crate) fn resolve_target_trait(
         .and_then(ast::PathType::cast)?
         .path()?;
 
-    match analyzer.resolve_path(db, &ast_path) {
+    match sema.resolve_path(&ast_path) {
         Some(hir::PathResolution::Def(hir::ModuleDef::Trait(def))) => Some(def),
         _ => None,
     }
diff --git a/crates/ra_cargo_watch/Cargo.toml b/crates/ra_cargo_watch/Cargo.toml
index b09650d98..1fdbffea1 100644
--- a/crates/ra_cargo_watch/Cargo.toml
+++ b/crates/ra_cargo_watch/Cargo.toml
@@ -6,13 +6,10 @@ authors = ["rust-analyzer developers"]
 
 [dependencies]
 crossbeam-channel = "0.4.0"
-lsp-types = { version = "0.70.1", features = ["proposed"] }
+lsp-types = { version = "0.71.0", features = ["proposed"] }
 log = "0.4.8"
 cargo_metadata = "0.9.1"
-jod-thread = "0.1.0"
-parking_lot = "0.10.0"
 serde_json = "1.0.48"
 
 [dev-dependencies]
 insta = "0.13.1"
-serde_json = "1.0.48"
diff --git a/crates/ra_hir/src/from_id.rs b/crates/ra_hir/src/from_id.rs
index c16c17072..3aa7c4870 100644
--- a/crates/ra_hir/src/from_id.rs
+++ b/crates/ra_hir/src/from_id.rs
@@ -40,6 +40,7 @@ from_id![
     (hir_def::ConstId, crate::Const),
     (hir_def::FunctionId, crate::Function),
     (hir_def::ImplId, crate::ImplBlock),
+    (hir_def::TypeParamId, crate::TypeParam),
     (hir_expand::MacroDefId, crate::MacroDef)
 ];
 
diff --git a/crates/ra_hir/src/lib.rs b/crates/ra_hir/src/lib.rs
index 7a9745ebe..4a85e7e36 100644
--- a/crates/ra_hir/src/lib.rs
+++ b/crates/ra_hir/src/lib.rs
@@ -26,6 +26,7 @@ macro_rules! impl_froms {
     }
 }
 
+mod semantics;
 pub mod db;
 pub mod source_analyzer;
 pub mod source_binder;
@@ -45,8 +46,8 @@ pub use crate::{
         StructField, Trait, Type, TypeAlias, TypeParam, Union, VariantDef,
     },
     has_source::HasSource,
-    source_analyzer::{PathResolution, ScopeEntryWithSyntax, SourceAnalyzer},
-    source_binder::SourceBinder,
+    semantics::{original_range, Semantics, SemanticsScope},
+    source_analyzer::PathResolution,
 };
 
 pub use hir_def::{
diff --git a/crates/ra_hir/src/semantics.rs b/crates/ra_hir/src/semantics.rs
new file mode 100644
index 000000000..c3d8ee1ae
--- /dev/null
+++ b/crates/ra_hir/src/semantics.rs
@@ -0,0 +1,412 @@
+//! See `Semantics`.
+
+use std::{cell::RefCell, fmt, iter::successors};
+
+use hir_def::{
+    resolver::{self, HasResolver, Resolver},
+    DefWithBodyId, TraitId,
+};
+use ra_db::{FileId, FileRange};
+use ra_syntax::{
+    algo::{find_covering_element, skip_trivia_token},
+    ast, match_ast, AstNode, Direction, NodeOrToken, SyntaxElement, SyntaxNode, SyntaxToken,
+    TextRange, TextUnit,
+};
+use rustc_hash::{FxHashMap, FxHashSet};
+
+use crate::{
+    db::HirDatabase,
+    source_analyzer::{resolve_hir_path, ReferenceDescriptor, SourceAnalyzer},
+    source_binder::{ChildContainer, SourceBinder},
+    Function, HirFileId, InFile, Local, MacroDef, Module, Name, Origin, Path, PathResolution,
+    ScopeDef, StructField, Trait, Type, TypeParam, VariantDef,
+};
+use ra_prof::profile;
+
+/// Primary API to get semantic information, like types, from syntax trees.
+pub struct Semantics<'db, DB> {
+    pub db: &'db DB,
+    pub(crate) sb: RefCell<SourceBinder>,
+    cache: RefCell<FxHashMap<SyntaxNode, HirFileId>>,
+}
+
+impl<DB> fmt::Debug for Semantics<'_, DB> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "Semantics {{ ... }}")
+    }
+}
+
+impl<'db, DB: HirDatabase> Semantics<'db, DB> {
+    pub fn new(db: &DB) -> Semantics<DB> {
+        let sb = RefCell::new(SourceBinder::new());
+        Semantics { db, sb, cache: RefCell::default() }
+    }
+
+    pub fn parse(&self, file_id: FileId) -> ast::SourceFile {
+        let tree = self.db.parse(file_id).tree();
+        self.cache(tree.syntax().clone(), file_id.into());
+        tree
+    }
+
+    pub fn expand(&self, macro_call: &ast::MacroCall) -> Option<SyntaxNode> {
+        let macro_call = self.find_file(macro_call.syntax().clone()).with_value(macro_call);
+        let sa = self.analyze2(macro_call.map(|it| it.syntax()), None);
+        let file_id = sa.expand(self.db, macro_call)?;
+        let node = self.db.parse_or_expand(file_id)?;
+        self.cache(node.clone(), file_id);
+        Some(node)
+    }
+
+    pub fn descend_into_macros(&self, token: SyntaxToken) -> SyntaxToken {
+        let parent = token.parent();
+        let parent = self.find_file(parent);
+        let sa = self.analyze2(parent.as_ref(), None);
+
+        let token = successors(Some(parent.with_value(token)), |token| {
+            let macro_call = token.value.ancestors().find_map(ast::MacroCall::cast)?;
+            let tt = macro_call.token_tree()?;
+            if !token.value.text_range().is_subrange(&tt.syntax().text_range()) {
+                return None;
+            }
+            let file_id = sa.expand(self.db, token.with_value(&macro_call))?;
+            let token = file_id.expansion_info(self.db)?.map_token_down(token.as_ref())?;
+
+            self.cache(find_root(&token.value.parent()), token.file_id);
+
+            Some(token)
+        })
+        .last()
+        .unwrap();
+
+        token.value
+    }
+
+    pub fn original_range(&self, node: &SyntaxNode) -> FileRange {
+        let node = self.find_file(node.clone());
+        original_range(self.db, node.as_ref())
+    }
+
+    pub fn ancestors_with_macros(&self, node: SyntaxNode) -> impl Iterator<Item = SyntaxNode> + '_ {
+        let node = self.find_file(node);
+        node.ancestors_with_macros(self.db).map(|it| it.value)
+    }
+
+    pub fn type_of_expr(&self, expr: &ast::Expr) -> Option<Type> {
+        self.analyze(expr.syntax()).type_of(self.db, &expr)
+    }
+
+    pub fn type_of_pat(&self, pat: &ast::Pat) -> Option<Type> {
+        self.analyze(pat.syntax()).type_of_pat(self.db, &pat)
+    }
+
+    pub fn resolve_method_call(&self, call: &ast::MethodCallExpr) -> Option<Function> {
+        self.analyze(call.syntax()).resolve_method_call(call)
+    }
+
+    pub fn resolve_field(&self, field: &ast::FieldExpr) -> Option<StructField> {
+        self.analyze(field.syntax()).resolve_field(field)
+    }
+
+    pub fn resolve_record_field(&self, field: &ast::RecordField) -> Option<StructField> {
+        self.analyze(field.syntax()).resolve_record_field(field)
+    }
+
+    pub fn resolve_record_literal(&self, record_lit: &ast::RecordLit) -> Option<VariantDef> {
+        self.analyze(record_lit.syntax()).resolve_record_literal(record_lit)
+    }
+
+    pub fn resolve_record_pattern(&self, record_pat: &ast::RecordPat) -> Option<VariantDef> {
+        self.analyze(record_pat.syntax()).resolve_record_pattern(record_pat)
+    }
+
+    pub fn resolve_macro_call(&self, macro_call: &ast::MacroCall) -> Option<MacroDef> {
+        let sa = self.analyze(macro_call.syntax());
+        let macro_call = self.find_file(macro_call.syntax().clone()).with_value(macro_call);
+        sa.resolve_macro_call(self.db, macro_call)
+    }
+
+    pub fn resolve_path(&self, path: &ast::Path) -> Option<PathResolution> {
+        self.analyze(path.syntax()).resolve_path(self.db, path)
+    }
+
+    // FIXME: use this instead?
+    // pub fn resolve_name_ref(&self, name_ref: &ast::NameRef) -> Option<???>;
+
+    pub fn to_def<T: ToDef + Clone>(&self, src: &T) -> Option<T::Def> {
+        T::to_def(self, src)
+    }
+
+    pub fn to_module_def(&self, file: FileId) -> Option<Module> {
+        let mut sb = self.sb.borrow_mut();
+        sb.to_module_def(self.db, file)
+    }
+
+    pub fn scope(&self, node: &SyntaxNode) -> SemanticsScope<'db, DB> {
+        let node = self.find_file(node.clone());
+        let resolver = self.analyze2(node.as_ref(), None).resolver;
+        SemanticsScope { db: self.db, resolver }
+    }
+
+    pub fn scope_at_offset(&self, node: &SyntaxNode, offset: TextUnit) -> SemanticsScope<'db, DB> {
+        let node = self.find_file(node.clone());
+        let resolver = self.analyze2(node.as_ref(), Some(offset)).resolver;
+        SemanticsScope { db: self.db, resolver }
+    }
+
+    pub fn scope_for_def(&self, def: Trait) -> SemanticsScope<'db, DB> {
+        let resolver = def.id.resolver(self.db);
+        SemanticsScope { db: self.db, resolver }
+    }
+
+    // FIXME: we only use this in `inline_local_variable` assist, ideally, we
+    // should switch to general reference search infra there.
+    pub fn find_all_refs(&self, pat: &ast::BindPat) -> Vec<ReferenceDescriptor> {
+        self.analyze(pat.syntax()).find_all_refs(pat)
+    }
+
+    fn analyze(&self, node: &SyntaxNode) -> SourceAnalyzer {
+        let src = self.find_file(node.clone());
+        self.analyze2(src.as_ref(), None)
+    }
+
+    fn analyze2(&self, src: InFile<&SyntaxNode>, offset: Option<TextUnit>) -> SourceAnalyzer {
+        let _p = profile("Semantics::analyze2");
+
+        let container = match self.sb.borrow_mut().find_container(self.db, src) {
+            Some(it) => it,
+            None => return SourceAnalyzer::new_for_resolver(Resolver::default(), src),
+        };
+
+        let resolver = match container {
+            ChildContainer::DefWithBodyId(def) => {
+                return SourceAnalyzer::new_for_body(self.db, def, src, offset)
+            }
+            ChildContainer::TraitId(it) => it.resolver(self.db),
+            ChildContainer::ImplId(it) => it.resolver(self.db),
+            ChildContainer::ModuleId(it) => it.resolver(self.db),
+            ChildContainer::EnumId(it) => it.resolver(self.db),
+            ChildContainer::VariantId(it) => it.resolver(self.db),
+            ChildContainer::GenericDefId(it) => it.resolver(self.db),
+        };
+        SourceAnalyzer::new_for_resolver(resolver, src)
+    }
+
+    fn cache(&self, root_node: SyntaxNode, file_id: HirFileId) {
+        assert!(root_node.parent().is_none());
+        let mut cache = self.cache.borrow_mut();
+        let prev = cache.insert(root_node, file_id);
+        assert!(prev == None || prev == Some(file_id))
+    }
+
+    pub fn assert_contains_node(&self, node: &SyntaxNode) {
+        self.find_file(node.clone());
+    }
+
+    fn lookup(&self, root_node: &SyntaxNode) -> Option<HirFileId> {
+        let cache = self.cache.borrow();
+        cache.get(root_node).copied()
+    }
+
+    fn find_file(&self, node: SyntaxNode) -> InFile<SyntaxNode> {
+        let root_node = find_root(&node);
+        let file_id = self.lookup(&root_node).unwrap_or_else(|| {
+            panic!(
+                "\n\nFailed to lookup {:?} in this Semantics.\n\
+                 Make sure to use only query nodes, derived from this instance of Semantics.\n\
+                 root node:   {:?}\n\
+                 known nodes: {}\n\n",
+                node,
+                root_node,
+                self.cache
+                    .borrow()
+                    .keys()
+                    .map(|it| format!("{:?}", it))
+                    .collect::<Vec<_>>()
+                    .join(", ")
+            )
+        });
+        InFile::new(file_id, node)
+    }
+}
+
+pub trait ToDef: Sized + AstNode + 'static {
+    type Def;
+    fn to_def<DB: HirDatabase>(sema: &Semantics<DB>, src: &Self) -> Option<Self::Def>;
+}
+
+macro_rules! to_def_impls {
+    ($(($def:path, $ast:path)),* ,) => {$(
+        impl ToDef for $ast {
+            type Def = $def;
+            fn to_def<DB: HirDatabase>(sema: &Semantics<DB>, src: &Self)
+                -> Option<Self::Def>
+            {
+                let src = sema.find_file(src.syntax().clone()).with_value(src);
+                sema.sb.borrow_mut().to_id(sema.db, src.cloned()).map(Into::into)
+            }
+        }
+    )*}
+}
+
+to_def_impls![
+    (crate::Module, ast::Module),
+    (crate::Struct, ast::StructDef),
+    (crate::Enum, ast::EnumDef),
+    (crate::Union, ast::UnionDef),
+    (crate::Trait, ast::TraitDef),
+    (crate::ImplBlock, ast::ImplBlock),
+    (crate::TypeAlias, ast::TypeAliasDef),
+    (crate::Const, ast::ConstDef),
+    (crate::Static, ast::StaticDef),
+    (crate::Function, ast::FnDef),
+    (crate::StructField, ast::RecordFieldDef),
+    (crate::EnumVariant, ast::EnumVariant),
+    (crate::TypeParam, ast::TypeParam),
+    (crate::MacroDef, ast::MacroCall), // this one is dubious, not all calls are macros
+];
+
+impl ToDef for ast::BindPat {
+    type Def = Local;
+
+    fn to_def<DB: HirDatabase>(sema: &Semantics<DB>, src: &Self) -> Option<Local> {
+        let src = sema.find_file(src.syntax().clone()).with_value(src);
+        let file_id = src.file_id;
+        let mut sb = sema.sb.borrow_mut();
+        let db = sema.db;
+        let parent: DefWithBodyId = src.value.syntax().ancestors().find_map(|it| {
+            let res = match_ast! {
+                match it {
+                    ast::ConstDef(value) => { sb.to_id(db, InFile { value, file_id})?.into() },
+                    ast::StaticDef(value) => { sb.to_id(db, InFile { value, file_id})?.into() },
+                    ast::FnDef(value) => { sb.to_id(db, InFile { value, file_id})?.into() },
+                    _ => return None,
+                }
+            };
+            Some(res)
+        })?;
+        let (_body, source_map) = db.body_with_source_map(parent);
+        let src = src.cloned().map(ast::Pat::from);
+        let pat_id = source_map.node_pat(src.as_ref())?;
+        Some(Local { parent: parent.into(), pat_id })
+    }
+}
+
+fn find_root(node: &SyntaxNode) -> SyntaxNode {
+    node.ancestors().last().unwrap()
+}
+
+pub struct SemanticsScope<'a, DB> {
+    pub db: &'a DB,
+    resolver: Resolver,
+}
+
+impl<'a, DB: HirDatabase> SemanticsScope<'a, DB> {
+    pub fn module(&self) -> Option<Module> {
+        Some(Module { id: self.resolver.module()? })
+    }
+
+    /// Note: `FxHashSet<TraitId>` should be treated as an opaque type, passed into `Type
+    // FIXME: rename to visible_traits to not repeat scope?
+    pub fn traits_in_scope(&self) -> FxHashSet<TraitId> {
+        let resolver = &self.resolver;
+        resolver.traits_in_scope(self.db)
+    }
+
+    pub fn process_all_names(&self, f: &mut dyn FnMut(Name, ScopeDef)) {
+        let resolver = &self.resolver;
+
+        resolver.process_all_names(self.db, &mut |name, def| {
+            let def = match def {
+                resolver::ScopeDef::PerNs(it) => it.into(),
+                resolver::ScopeDef::ImplSelfType(it) => ScopeDef::ImplSelfType(it.into()),
+                resolver::ScopeDef::AdtSelfType(it) => ScopeDef::AdtSelfType(it.into()),
+                resolver::ScopeDef::GenericParam(id) => ScopeDef::GenericParam(TypeParam { id }),
+                resolver::ScopeDef::Local(pat_id) => {
+                    let parent = resolver.body_owner().unwrap().into();
+                    ScopeDef::Local(Local { parent, pat_id })
+                }
+            };
+            f(name, def)
+        })
+    }
+
+    pub fn resolve_hir_path(&self, path: &Path) -> Option<PathResolution> {
+        resolve_hir_path(self.db, &self.resolver, path)
+    }
+}
+
+// FIXME: Change `HasSource` trait to work with `Semantics` and remove this?
+pub fn original_range(db: &impl HirDatabase, node: InFile<&SyntaxNode>) -> FileRange {
+    let mut elem: InFile<SyntaxElement> = node.map(|n| n.clone().into());
+
+    while let Some((range, Origin::Call)) = original_range_and_origin(db, elem.as_ref()) {
+        let original_file = range.file_id.original_file(db);
+
+        if range.file_id == original_file.into() {
+            return FileRange { file_id: original_file, range: range.value };
+        }
+
+        if range.file_id != elem.file_id {
+            if let Some(root) = db.parse_or_expand(range.file_id) {
+                elem = range.with_value(find_covering_element(&root, range.value));
+                continue;
+            }
+        }
+
+        log::error!("Fail to mapping up more for {:?}", range);
+        return FileRange { file_id: range.file_id.original_file(db), range: range.value };
+    }
+
+    // Fall back to whole macro call
+    if let Some(expansion) = node.file_id.expansion_info(db) {
+        if let Some(call_node) = expansion.call_node() {
+            return FileRange {
+                file_id: call_node.file_id.original_file(db),
+                range: call_node.value.text_range(),
+            };
+        }
+    }
+
+    FileRange { file_id: node.file_id.original_file(db), range: node.value.text_range() }
+}
+
+fn original_range_and_origin(
+    db: &impl HirDatabase,
+    elem: InFile<&SyntaxElement>,
+) -> Option<(InFile<TextRange>, Origin)> {
+    let expansion = elem.file_id.expansion_info(db)?;
+
+    let node = match elem.as_ref().value {
+        NodeOrToken::Node(it) => elem.with_value(it),
+        NodeOrToken::Token(it) => {
+            let (tt, origin) = expansion.map_token_up(elem.with_value(it))?;
+            return Some((tt.map(|it| it.text_range()), origin));
+        }
+    };
+
+    // the input node has only one token ?
+    let single = skip_trivia_token(node.value.first_token()?, Direction::Next)?
+        == skip_trivia_token(node.value.last_token()?, Direction::Prev)?;
+
+    Some(node.value.descendants().find_map(|it| {
+        let first = skip_trivia_token(it.first_token()?, Direction::Next)?;
+        let last = skip_trivia_token(it.last_token()?, Direction::Prev)?;
+
+        if !single && first == last {
+            return None;
+        }
+
+        // Try to map first and last tokens of node, and, if success, return the union range of mapped tokens
+        let (first, first_origin) = expansion.map_token_up(node.with_value(&first))?;
+        let (last, last_origin) = expansion.map_token_up(node.with_value(&last))?;
+
+        if first.file_id != last.file_id || first_origin != last_origin {
+            return None;
+        }
+
+        Some((
+            first.with_value(first.value.text_range().extend_to(&last.value.text_range())),
+            first_origin,
+        ))
+    })?)
+}
diff --git a/crates/ra_hir/src/source_analyzer.rs b/crates/ra_hir/src/source_analyzer.rs
index efa3f8a79..b655e2c32 100644
--- a/crates/ra_hir/src/source_analyzer.rs
+++ b/crates/ra_hir/src/source_analyzer.rs
@@ -14,29 +14,27 @@ use hir_def::{
         BodySourceMap,
     },
     expr::{ExprId, PatId},
-    resolver::{self, resolver_for_scope, Resolver, TypeNs, ValueNs},
-    AsMacroCall, DefWithBodyId, TraitId,
+    resolver::{resolver_for_scope, Resolver, TypeNs, ValueNs},
+    AsMacroCall, DefWithBodyId,
 };
-use hir_expand::{hygiene::Hygiene, name::AsName, HirFileId, InFile, MacroCallId};
+use hir_expand::{hygiene::Hygiene, name::AsName, HirFileId, InFile};
 use hir_ty::{InEnvironment, InferenceResult, TraitEnvironment};
 use ra_syntax::{
     ast::{self, AstNode},
-    AstPtr, SyntaxNode, SyntaxNodePtr, SyntaxToken, TextRange, TextUnit,
+    AstPtr, SyntaxNode, SyntaxNodePtr, TextRange, TextUnit,
 };
-use rustc_hash::FxHashSet;
 
 use crate::{
-    db::HirDatabase, Adt, Const, DefWithBody, EnumVariant, Function, Local, MacroDef, Name, Path,
-    ScopeDef, Static, Struct, Trait, Type, TypeAlias, TypeParam,
+    db::HirDatabase, Adt, Const, EnumVariant, Function, Local, MacroDef, Path, Static, Struct,
+    Trait, Type, TypeAlias, TypeParam,
 };
 
 /// `SourceAnalyzer` is a convenience wrapper which exposes HIR API in terms of
 /// original source files. It should not be used inside the HIR itself.
 #[derive(Debug)]
-pub struct SourceAnalyzer {
+pub(crate) struct SourceAnalyzer {
     file_id: HirFileId,
-    resolver: Resolver,
-    body_owner: Option<DefWithBody>,
+    pub(crate) resolver: Resolver,
     body_source_map: Option<Arc<BodySourceMap>>,
     infer: Option<Arc<InferenceResult>>,
     scopes: Option<Arc<ExprScopes>>,
@@ -55,57 +53,13 @@ pub enum PathResolution {
     AssocItem(crate::AssocItem),
 }
 
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub struct ScopeEntryWithSyntax {
-    pub(crate) name: Name,
-    pub(crate) ptr: Either<AstPtr<ast::Pat>, AstPtr<ast::SelfParam>>,
-}
-
-impl ScopeEntryWithSyntax {
-    pub fn name(&self) -> &Name {
-        &self.name
-    }
-
-    pub fn ptr(&self) -> Either<AstPtr<ast::Pat>, AstPtr<ast::SelfParam>> {
-        self.ptr
-    }
-}
-
 #[derive(Debug)]
 pub struct ReferenceDescriptor {
     pub range: TextRange,
     pub name: String,
 }
 
-#[derive(Debug)]
-pub struct Expansion {
-    macro_call_id: MacroCallId,
-}
-
-impl Expansion {
-    pub fn map_token_down(
-        &self,
-        db: &impl HirDatabase,
-        token: InFile<&SyntaxToken>,
-    ) -> Option<InFile<SyntaxToken>> {
-        let exp_info = self.file_id().expansion_info(db)?;
-        exp_info.map_token_down(token)
-    }
-
-    pub fn file_id(&self) -> HirFileId {
-        self.macro_call_id.as_file()
-    }
-}
-
 impl SourceAnalyzer {
-    pub fn new(
-        db: &impl HirDatabase,
-        node: InFile<&SyntaxNode>,
-        offset: Option<TextUnit>,
-    ) -> SourceAnalyzer {
-        crate::source_binder::SourceBinder::new(db).analyze(node, offset)
-    }
-
     pub(crate) fn new_for_body(
         db: &impl HirDatabase,
         def: DefWithBodyId,
@@ -121,7 +75,6 @@ impl SourceAnalyzer {
         let resolver = resolver_for_scope(db, def, scope);
         SourceAnalyzer {
             resolver,
-            body_owner: Some(def.into()),
             body_source_map: Some(source_map),
             infer: Some(db.infer(def)),
             scopes: Some(scopes),
@@ -135,7 +88,6 @@ impl SourceAnalyzer {
     ) -> SourceAnalyzer {
         SourceAnalyzer {
             resolver,
-            body_owner: None,
             body_source_map: None,
             infer: None,
             scopes: None,
@@ -143,10 +95,6 @@ impl SourceAnalyzer {
         }
     }
 
-    pub fn module(&self) -> Option<crate::code_model::Module> {
-        Some(crate::code_model::Module { id: self.resolver.module()? })
-    }
-
     fn expr_id(&self, expr: &ast::Expr) -> Option<ExprId> {
         let src = InFile { file_id: self.file_id, value: expr };
         self.body_source_map.as_ref()?.node_expr(src)
@@ -180,7 +128,7 @@ impl SourceAnalyzer {
         TraitEnvironment::lower(db, &self.resolver)
     }
 
-    pub fn type_of(&self, db: &impl HirDatabase, expr: &ast::Expr) -> Option<Type> {
+    pub(crate) fn type_of(&self, db: &impl HirDatabase, expr: &ast::Expr) -> Option<Type> {
         let expr_id = if let Some(expr) = self.expand_expr(db, InFile::new(self.file_id, expr)) {
             self.body_source_map.as_ref()?.node_expr(expr.as_ref())?
         } else {
@@ -192,24 +140,27 @@ impl SourceAnalyzer {
         Some(Type { krate: self.resolver.krate()?, ty: InEnvironment { value: ty, environment } })
     }
 
-    pub fn type_of_pat(&self, db: &impl HirDatabase, pat: &ast::Pat) -> Option<Type> {
+    pub(crate) fn type_of_pat(&self, db: &impl HirDatabase, pat: &ast::Pat) -> Option<Type> {
         let pat_id = self.pat_id(pat)?;
         let ty = self.infer.as_ref()?[pat_id].clone();
         let environment = self.trait_env(db);
         Some(Type { krate: self.resolver.krate()?, ty: InEnvironment { value: ty, environment } })
     }
 
-    pub fn resolve_method_call(&self, call: &ast::MethodCallExpr) -> Option<Function> {
+    pub(crate) fn resolve_method_call(&self, call: &ast::MethodCallExpr) -> Option<Function> {
         let expr_id = self.expr_id(&call.clone().into())?;
         self.infer.as_ref()?.method_resolution(expr_id).map(Function::from)
     }
 
-    pub fn resolve_field(&self, field: &ast::FieldExpr) -> Option<crate::StructField> {
+    pub(crate) fn resolve_field(&self, field: &ast::FieldExpr) -> Option<crate::StructField> {
         let expr_id = self.expr_id(&field.clone().into())?;
         self.infer.as_ref()?.field_resolution(expr_id).map(|it| it.into())
     }
 
-    pub fn resolve_record_field(&self, field: &ast::RecordField) -> Option<crate::StructField> {
+    pub(crate) fn resolve_record_field(
+        &self,
+        field: &ast::RecordField,
+    ) -> Option<crate::StructField> {
         let expr_id = match field.expr() {
             Some(it) => self.expr_id(&it)?,
             None => {
@@ -220,17 +171,23 @@ impl SourceAnalyzer {
         self.infer.as_ref()?.record_field_resolution(expr_id).map(|it| it.into())
     }
 
-    pub fn resolve_record_literal(&self, record_lit: &ast::RecordLit) -> Option<crate::VariantDef> {
+    pub(crate) fn resolve_record_literal(
+        &self,
+        record_lit: &ast::RecordLit,
+    ) -> Option<crate::VariantDef> {
         let expr_id = self.expr_id(&record_lit.clone().into())?;
         self.infer.as_ref()?.variant_resolution_for_expr(expr_id).map(|it| it.into())
     }
 
-    pub fn resolve_record_pattern(&self, record_pat: &ast::RecordPat) -> Option<crate::VariantDef> {
+    pub(crate) fn resolve_record_pattern(
+        &self,
+        record_pat: &ast::RecordPat,
+    ) -> Option<crate::VariantDef> {
         let pat_id = self.pat_id(&record_pat.clone().into())?;
         self.infer.as_ref()?.variant_resolution_for_pat(pat_id).map(|it| it.into())
     }
 
-    pub fn resolve_macro_call(
+    pub(crate) fn resolve_macro_call(
         &self,
         db: &impl HirDatabase,
         macro_call: InFile<&ast::MacroCall>,
@@ -240,52 +197,11 @@ impl SourceAnalyzer {
         self.resolver.resolve_path_as_macro(db, path.mod_path()).map(|it| it.into())
     }
 
-    pub fn resolve_hir_path(
+    pub(crate) fn resolve_path(
         &self,
         db: &impl HirDatabase,
-        path: &crate::Path,
+        path: &ast::Path,
     ) -> Option<PathResolution> {
-        let types =
-            self.resolver.resolve_path_in_type_ns_fully(db, path.mod_path()).map(|ty| match ty {
-                TypeNs::SelfType(it) => PathResolution::SelfType(it.into()),
-                TypeNs::GenericParam(id) => PathResolution::TypeParam(TypeParam { id }),
-                TypeNs::AdtSelfType(it) | TypeNs::AdtId(it) => {
-                    PathResolution::Def(Adt::from(it).into())
-                }
-                TypeNs::EnumVariantId(it) => PathResolution::Def(EnumVariant::from(it).into()),
-                TypeNs::TypeAliasId(it) => PathResolution::Def(TypeAlias::from(it).into()),
-                TypeNs::BuiltinType(it) => PathResolution::Def(it.into()),
-                TypeNs::TraitId(it) => PathResolution::Def(Trait::from(it).into()),
-            });
-        let values =
-            self.resolver.resolve_path_in_value_ns_fully(db, path.mod_path()).and_then(|val| {
-                let res = match val {
-                    ValueNs::LocalBinding(pat_id) => {
-                        let var = Local { parent: self.body_owner?, pat_id };
-                        PathResolution::Local(var)
-                    }
-                    ValueNs::FunctionId(it) => PathResolution::Def(Function::from(it).into()),
-                    ValueNs::ConstId(it) => PathResolution::Def(Const::from(it).into()),
-                    ValueNs::StaticId(it) => PathResolution::Def(Static::from(it).into()),
-                    ValueNs::StructId(it) => PathResolution::Def(Struct::from(it).into()),
-                    ValueNs::EnumVariantId(it) => PathResolution::Def(EnumVariant::from(it).into()),
-                };
-                Some(res)
-            });
-
-        let items = self
-            .resolver
-            .resolve_module_path_in_items(db, path.mod_path())
-            .take_types()
-            .map(|it| PathResolution::Def(it.into()));
-        types.or(values).or(items).or_else(|| {
-            self.resolver
-                .resolve_path_as_macro(db, path.mod_path())
-                .map(|def| PathResolution::Macro(def.into()))
-        })
-    }
-
-    pub fn resolve_path(&self, db: &impl HirDatabase, path: &ast::Path) -> Option<PathResolution> {
         if let Some(path_expr) = path.syntax().parent().and_then(ast::PathExpr::cast) {
             let expr_id = self.expr_id(&path_expr.into())?;
             if let Some(assoc) = self.infer.as_ref()?.assoc_resolutions_for_expr(expr_id) {
@@ -300,40 +216,24 @@ impl SourceAnalyzer {
         }
         // This must be a normal source file rather than macro file.
         let hir_path = crate::Path::from_ast(path.clone())?;
-        self.resolve_hir_path(db, &hir_path)
+        resolve_hir_path(db, &self.resolver, &hir_path)
     }
 
-    fn resolve_local_name(&self, name_ref: &ast::NameRef) -> Option<ScopeEntryWithSyntax> {
+    fn resolve_local_name(
+        &self,
+        name_ref: &ast::NameRef,
+    ) -> Option<Either<AstPtr<ast::Pat>, AstPtr<ast::SelfParam>>> {
         let name = name_ref.as_name();
         let source_map = self.body_source_map.as_ref()?;
         let scopes = self.scopes.as_ref()?;
         let scope = scope_for(scopes, source_map, InFile::new(self.file_id, name_ref.syntax()))?;
         let entry = scopes.resolve_name_in_scope(scope, &name)?;
-        Some(ScopeEntryWithSyntax {
-            name: entry.name().clone(),
-            ptr: source_map.pat_syntax(entry.pat())?.value,
-        })
-    }
-
-    pub fn process_all_names(&self, db: &impl HirDatabase, f: &mut dyn FnMut(Name, ScopeDef)) {
-        self.resolver.process_all_names(db, &mut |name, def| {
-            let def = match def {
-                resolver::ScopeDef::PerNs(it) => it.into(),
-                resolver::ScopeDef::ImplSelfType(it) => ScopeDef::ImplSelfType(it.into()),
-                resolver::ScopeDef::AdtSelfType(it) => ScopeDef::AdtSelfType(it.into()),
-                resolver::ScopeDef::GenericParam(id) => ScopeDef::GenericParam(TypeParam { id }),
-                resolver::ScopeDef::Local(pat_id) => {
-                    let parent = self.resolver.body_owner().unwrap().into();
-                    ScopeDef::Local(Local { parent, pat_id })
-                }
-            };
-            f(name, def)
-        })
+        Some(source_map.pat_syntax(entry.pat())?.value)
     }
 
     // FIXME: we only use this in `inline_local_variable` assist, ideally, we
     // should switch to general reference search infra there.
-    pub fn find_all_refs(&self, pat: &ast::BindPat) -> Vec<ReferenceDescriptor> {
+    pub(crate) fn find_all_refs(&self, pat: &ast::BindPat) -> Vec<ReferenceDescriptor> {
         let fn_def = pat.syntax().ancestors().find_map(ast::FnDef::cast).unwrap();
         let ptr = Either::Left(AstPtr::new(&ast::Pat::from(pat.clone())));
         fn_def
@@ -342,7 +242,7 @@ impl SourceAnalyzer {
             .filter_map(ast::NameRef::cast)
             .filter(|name_ref| match self.resolve_local_name(&name_ref) {
                 None => false,
-                Some(entry) => entry.ptr() == ptr,
+                Some(d_ptr) => d_ptr == ptr,
             })
             .map(|name_ref| ReferenceDescriptor {
                 name: name_ref.text().to_string(),
@@ -351,19 +251,14 @@ impl SourceAnalyzer {
             .collect()
     }
 
-    /// Note: `FxHashSet<TraitId>` should be treated as an opaque type, passed into `Type
-    pub fn traits_in_scope(&self, db: &impl HirDatabase) -> FxHashSet<TraitId> {
-        self.resolver.traits_in_scope(db)
-    }
-
-    pub fn expand(
+    pub(crate) fn expand(
         &self,
         db: &impl HirDatabase,
         macro_call: InFile<&ast::MacroCall>,
-    ) -> Option<Expansion> {
+    ) -> Option<HirFileId> {
         let macro_call_id =
             macro_call.as_call_id(db, |path| self.resolver.resolve_path_as_macro(db, &path))?;
-        Some(Expansion { macro_call_id })
+        Some(macro_call_id.as_file())
     }
 }
 
@@ -409,6 +304,47 @@ fn scope_for_offset(
         })
 }
 
+pub(crate) fn resolve_hir_path(
+    db: &impl HirDatabase,
+    resolver: &Resolver,
+    path: &crate::Path,
+) -> Option<PathResolution> {
+    let types = resolver.resolve_path_in_type_ns_fully(db, path.mod_path()).map(|ty| match ty {
+        TypeNs::SelfType(it) => PathResolution::SelfType(it.into()),
+        TypeNs::GenericParam(id) => PathResolution::TypeParam(TypeParam { id }),
+        TypeNs::AdtSelfType(it) | TypeNs::AdtId(it) => PathResolution::Def(Adt::from(it).into()),
+        TypeNs::EnumVariantId(it) => PathResolution::Def(EnumVariant::from(it).into()),
+        TypeNs::TypeAliasId(it) => PathResolution::Def(TypeAlias::from(it).into()),
+        TypeNs::BuiltinType(it) => PathResolution::Def(it.into()),
+        TypeNs::TraitId(it) => PathResolution::Def(Trait::from(it).into()),
+    });
+    let body_owner = resolver.body_owner();
+    let values = resolver.resolve_path_in_value_ns_fully(db, path.mod_path()).and_then(|val| {
+        let res = match val {
+            ValueNs::LocalBinding(pat_id) => {
+                let var = Local { parent: body_owner?.into(), pat_id };
+                PathResolution::Local(var)
+            }
+            ValueNs::FunctionId(it) => PathResolution::Def(Function::from(it).into()),
+            ValueNs::ConstId(it) => PathResolution::Def(Const::from(it).into()),
+            ValueNs::StaticId(it) => PathResolution::Def(Static::from(it).into()),
+            ValueNs::StructId(it) => PathResolution::Def(Struct::from(it).into()),
+            ValueNs::EnumVariantId(it) => PathResolution::Def(EnumVariant::from(it).into()),
+        };
+        Some(res)
+    });
+
+    let items = resolver
+        .resolve_module_path_in_items(db, path.mod_path())
+        .take_types()
+        .map(|it| PathResolution::Def(it.into()));
+    types.or(values).or(items).or_else(|| {
+        resolver
+            .resolve_path_as_macro(db, path.mod_path())
+            .map(|def| PathResolution::Macro(def.into()))
+    })
+}
+
 // XXX: during completion, cursor might be outside of any particular
 // expression. Try to figure out the correct scope...
 fn adjust(
diff --git a/crates/ra_hir/src/source_binder.rs b/crates/ra_hir/src/source_binder.rs
index f3150f578..4353e25ac 100644
--- a/crates/ra_hir/src/source_binder.rs
+++ b/crates/ra_hir/src/source_binder.rs
@@ -5,112 +5,89 @@ use hir_def::{
     child_by_source::ChildBySource,
     dyn_map::DynMap,
     keys::{self, Key},
-    resolver::{HasResolver, Resolver},
     ConstId, DefWithBodyId, EnumId, EnumVariantId, FunctionId, GenericDefId, ImplId, ModuleId,
-    StaticId, StructFieldId, StructId, TraitId, TypeAliasId, UnionId, VariantId,
+    StaticId, StructFieldId, StructId, TraitId, TypeAliasId, TypeParamId, UnionId, VariantId,
 };
 use hir_expand::{name::AsName, AstId, InFile, MacroDefId, MacroDefKind};
+use ra_db::FileId;
 use ra_prof::profile;
 use ra_syntax::{
     ast::{self, NameOwner},
-    match_ast, AstNode, SyntaxNode, TextUnit,
+    match_ast, AstNode, SyntaxNode,
 };
 use rustc_hash::FxHashMap;
 
-use crate::{db::HirDatabase, Local, Module, SourceAnalyzer, TypeParam};
-use ra_db::FileId;
+use crate::{db::HirDatabase, Module};
 
-pub struct SourceBinder<'a, DB> {
-    pub db: &'a DB,
+pub(crate) struct SourceBinder {
     child_by_source_cache: FxHashMap<ChildContainer, DynMap>,
 }
 
-impl<DB: HirDatabase> SourceBinder<'_, DB> {
-    pub fn new(db: &DB) -> SourceBinder<DB> {
-        SourceBinder { db, child_by_source_cache: FxHashMap::default() }
-    }
-
-    pub fn analyze(
-        &mut self,
-        src: InFile<&SyntaxNode>,
-        offset: Option<TextUnit>,
-    ) -> SourceAnalyzer {
-        let _p = profile("SourceBinder::analyzer");
-        let container = match self.find_container(src) {
-            Some(it) => it,
-            None => return SourceAnalyzer::new_for_resolver(Resolver::default(), src),
-        };
-
-        let resolver = match container {
-            ChildContainer::DefWithBodyId(def) => {
-                return SourceAnalyzer::new_for_body(self.db, def, src, offset)
-            }
-            ChildContainer::TraitId(it) => it.resolver(self.db),
-            ChildContainer::ImplId(it) => it.resolver(self.db),
-            ChildContainer::ModuleId(it) => it.resolver(self.db),
-            ChildContainer::EnumId(it) => it.resolver(self.db),
-            ChildContainer::VariantId(it) => it.resolver(self.db),
-            ChildContainer::GenericDefId(it) => it.resolver(self.db),
-        };
-        SourceAnalyzer::new_for_resolver(resolver, src)
-    }
-
-    pub fn to_def<T: ToDef>(&mut self, src: InFile<T>) -> Option<T::Def> {
-        T::to_def(self, src)
+impl SourceBinder {
+    pub(crate) fn new() -> SourceBinder {
+        SourceBinder { child_by_source_cache: FxHashMap::default() }
     }
 
-    pub fn to_module_def(&mut self, file: FileId) -> Option<Module> {
+    pub(crate) fn to_module_def(&mut self, db: &impl HirDatabase, file: FileId) -> Option<Module> {
         let _p = profile("SourceBinder::to_module_def");
-        let (krate, local_id) = self.db.relevant_crates(file).iter().find_map(|&crate_id| {
-            let crate_def_map = self.db.crate_def_map(crate_id);
+        let (krate, local_id) = db.relevant_crates(file).iter().find_map(|&crate_id| {
+            let crate_def_map = db.crate_def_map(crate_id);
             let local_id = crate_def_map.modules_for_file(file).next()?;
             Some((crate_id, local_id))
         })?;
         Some(Module { id: ModuleId { krate, local_id } })
     }
 
-    fn to_id<T: ToId>(&mut self, src: InFile<T>) -> Option<T::ID> {
-        T::to_id(self, src)
+    pub(crate) fn to_id<T: ToId>(
+        &mut self,
+        db: &impl HirDatabase,
+        src: InFile<T>,
+    ) -> Option<T::ID> {
+        T::to_id(db, self, src)
     }
 
-    fn find_container(&mut self, src: InFile<&SyntaxNode>) -> Option<ChildContainer> {
-        for container in src.cloned().ancestors_with_macros(self.db).skip(1) {
+    pub(crate) fn find_container(
+        &mut self,
+        db: &impl HirDatabase,
+        src: InFile<&SyntaxNode>,
+    ) -> Option<ChildContainer> {
+        for container in src.cloned().ancestors_with_macros(db).skip(1) {
             let res: ChildContainer = match_ast! {
                 match (container.value) {
                     ast::TraitDef(it) => {
-                        let def: TraitId = self.to_id(container.with_value(it))?;
+                        let def: TraitId = self.to_id(db, container.with_value(it))?;
                         def.into()
                     },
                     ast::ImplBlock(it) => {
-                        let def: ImplId = self.to_id(container.with_value(it))?;
+                        let def: ImplId = self.to_id(db, container.with_value(it))?;
                         def.into()
                     },
                     ast::FnDef(it) => {
-                        let def: FunctionId = self.to_id(container.with_value(it))?;
+                        let def: FunctionId = self.to_id(db, container.with_value(it))?;
                         DefWithBodyId::from(def).into()
                     },
                     ast::StaticDef(it) => {
-                        let def: StaticId = self.to_id(container.with_value(it))?;
+                        let def: StaticId = self.to_id(db, container.with_value(it))?;
                         DefWithBodyId::from(def).into()
                     },
                     ast::ConstDef(it) => {
-                        let def: ConstId = self.to_id(container.with_value(it))?;
+                        let def: ConstId = self.to_id(db, container.with_value(it))?;
                         DefWithBodyId::from(def).into()
                     },
                     ast::EnumDef(it) => {
-                        let def: EnumId = self.to_id(container.with_value(it))?;
+                        let def: EnumId = self.to_id(db, container.with_value(it))?;
                         def.into()
                     },
                     ast::StructDef(it) => {
-                        let def: StructId = self.to_id(container.with_value(it))?;
+                        let def: StructId = self.to_id(db, container.with_value(it))?;
                         VariantId::from(def).into()
                     },
                     ast::UnionDef(it) => {
-                        let def: UnionId = self.to_id(container.with_value(it))?;
+                        let def: UnionId = self.to_id(db, container.with_value(it))?;
                         VariantId::from(def).into()
                     },
                     ast::Module(it) => {
-                        let def: ModuleId = self.to_id(container.with_value(it))?;
+                        let def: ModuleId = self.to_id(db, container.with_value(it))?;
                         def.into()
                     },
                     _ => { continue },
@@ -119,12 +96,11 @@ impl<DB: HirDatabase> SourceBinder<'_, DB> {
             return Some(res);
         }
 
-        let c = self.to_module_def(src.file_id.original_file(self.db))?;
+        let c = self.to_module_def(db, src.file_id.original_file(db))?;
         Some(c.id.into())
     }
 
-    fn child_by_source(&mut self, container: ChildContainer) -> &DynMap {
-        let db = self.db;
+    fn child_by_source(&mut self, db: &impl HirDatabase, container: ChildContainer) -> &DynMap {
         self.child_by_source_cache.entry(container).or_insert_with(|| match container {
             ChildContainer::DefWithBodyId(it) => it.child_by_source(db),
             ChildContainer::ModuleId(it) => it.child_by_source(db),
@@ -137,49 +113,17 @@ impl<DB: HirDatabase> SourceBinder<'_, DB> {
     }
 }
 
-pub trait ToId: Sized {
+pub(crate) trait ToId: Sized {
     type ID: Sized + Copy + 'static;
-    fn to_id<DB: HirDatabase>(sb: &mut SourceBinder<'_, DB>, src: InFile<Self>)
-        -> Option<Self::ID>;
-}
-
-pub trait ToDef: Sized + AstNode + 'static {
-    type Def;
-    fn to_def<DB: HirDatabase>(
-        sb: &mut SourceBinder<'_, DB>,
+    fn to_id<DB: HirDatabase>(
+        db: &DB,
+        sb: &mut SourceBinder,
         src: InFile<Self>,
-    ) -> Option<Self::Def>;
-}
-
-macro_rules! to_def_impls {
-    ($(($def:path, $ast:path)),* ,) => {$(
-        impl ToDef for $ast {
-            type Def = $def;
-            fn to_def<DB: HirDatabase>(sb: &mut SourceBinder<'_, DB>, src: InFile<Self>)
-                -> Option<Self::Def>
-            { sb.to_id(src).map(Into::into) }
-        }
-    )*}
+    ) -> Option<Self::ID>;
 }
 
-to_def_impls![
-    (crate::Module, ast::Module),
-    (crate::Struct, ast::StructDef),
-    (crate::Enum, ast::EnumDef),
-    (crate::Union, ast::UnionDef),
-    (crate::Trait, ast::TraitDef),
-    (crate::ImplBlock, ast::ImplBlock),
-    (crate::TypeAlias, ast::TypeAliasDef),
-    (crate::Const, ast::ConstDef),
-    (crate::Static, ast::StaticDef),
-    (crate::Function, ast::FnDef),
-    (crate::StructField, ast::RecordFieldDef),
-    (crate::EnumVariant, ast::EnumVariant),
-    (crate::MacroDef, ast::MacroCall), // this one is dubious, not all calls are macros
-];
-
 #[derive(Clone, Copy, PartialEq, Eq, Hash, Debug)]
-enum ChildContainer {
+pub(crate) enum ChildContainer {
     DefWithBodyId(DefWithBodyId),
     ModuleId(ModuleId),
     TraitId(TraitId),
@@ -201,7 +145,7 @@ impl_froms! {
     GenericDefId
 }
 
-pub trait ToIdByKey: Sized + AstNode + 'static {
+pub(crate) trait ToIdByKey: Sized + AstNode + 'static {
     type ID: Sized + Copy + 'static;
     const KEY: Key<Self, Self::ID>;
 }
@@ -209,11 +153,11 @@ pub trait ToIdByKey: Sized + AstNode + 'static {
 impl<T: ToIdByKey> ToId for T {
     type ID = <T as ToIdByKey>::ID;
     fn to_id<DB: HirDatabase>(
-        sb: &mut SourceBinder<'_, DB>,
+        db: &DB,
+        sb: &mut SourceBinder,
         src: InFile<Self>,
     ) -> Option<Self::ID> {
-        let container = sb.find_container(src.as_ref().map(|it| it.syntax()))?;
-        let db = sb.db;
+        let container = sb.find_container(db, src.as_ref().map(|it| it.syntax()))?;
         let dyn_map =
             &*sb.child_by_source_cache.entry(container).or_insert_with(|| match container {
                 ChildContainer::DefWithBodyId(it) => it.child_by_source(db),
@@ -255,68 +199,44 @@ to_id_key_impls![
 impl ToId for ast::MacroCall {
     type ID = MacroDefId;
     fn to_id<DB: HirDatabase>(
-        sb: &mut SourceBinder<'_, DB>,
+        db: &DB,
+        sb: &mut SourceBinder,
         src: InFile<Self>,
     ) -> Option<Self::ID> {
         let kind = MacroDefKind::Declarative;
 
-        let krate = sb.to_module_def(src.file_id.original_file(sb.db))?.id.krate;
+        let krate = sb.to_module_def(db, src.file_id.original_file(db))?.id.krate;
 
-        let ast_id =
-            Some(AstId::new(src.file_id, sb.db.ast_id_map(src.file_id).ast_id(&src.value)));
+        let ast_id = Some(AstId::new(src.file_id, db.ast_id_map(src.file_id).ast_id(&src.value)));
 
         Some(MacroDefId { krate: Some(krate), ast_id, kind })
     }
 }
 
-impl ToDef for ast::BindPat {
-    type Def = Local;
-
-    fn to_def<DB: HirDatabase>(sb: &mut SourceBinder<'_, DB>, src: InFile<Self>) -> Option<Local> {
-        let file_id = src.file_id;
-        let parent: DefWithBodyId = src.value.syntax().ancestors().find_map(|it| {
-            let res = match_ast! {
-                match it {
-                    ast::ConstDef(value) => { sb.to_id(InFile { value, file_id})?.into() },
-                    ast::StaticDef(value) => { sb.to_id(InFile { value, file_id})?.into() },
-                    ast::FnDef(value) => { sb.to_id(InFile { value, file_id})?.into() },
-                    _ => return None,
-                }
-            };
-            Some(res)
-        })?;
-        let (_body, source_map) = sb.db.body_with_source_map(parent);
-        let src = src.map(ast::Pat::from);
-        let pat_id = source_map.node_pat(src.as_ref())?;
-        Some(Local { parent: parent.into(), pat_id })
-    }
-}
-
-impl ToDef for ast::TypeParam {
-    type Def = TypeParam;
+impl ToId for ast::TypeParam {
+    type ID = TypeParamId;
 
-    fn to_def<DB: HirDatabase>(
-        sb: &mut SourceBinder<'_, DB>,
-        src: InFile<ast::TypeParam>,
-    ) -> Option<TypeParam> {
-        let mut sb = SourceBinder::new(sb.db);
+    fn to_id<DB: HirDatabase>(
+        db: &DB,
+        sb: &mut SourceBinder,
+        src: InFile<Self>,
+    ) -> Option<Self::ID> {
         let file_id = src.file_id;
         let parent: GenericDefId = src.value.syntax().ancestors().find_map(|it| {
             let res = match_ast! {
                 match it {
-                    ast::FnDef(value) => { sb.to_id(InFile { value, file_id})?.into() },
-                    ast::StructDef(value) => { sb.to_id(InFile { value, file_id})?.into() },
-                    ast::EnumDef(value) => { sb.to_id(InFile { value, file_id})?.into() },
-                    ast::TraitDef(value) => { sb.to_id(InFile { value, file_id})?.into() },
-                    ast::TypeAliasDef(value) => { sb.to_id(InFile { value, file_id})?.into() },
-                    ast::ImplBlock(value) => { sb.to_id(InFile { value, file_id})?.into() },
+                    ast::FnDef(value) => { sb.to_id(db, InFile { value, file_id})?.into() },
+                    ast::StructDef(value) => { sb.to_id(db, InFile { value, file_id})?.into() },
+                    ast::EnumDef(value) => { sb.to_id(db, InFile { value, file_id})?.into() },
+                    ast::TraitDef(value) => { sb.to_id(db, InFile { value, file_id})?.into() },
+                    ast::TypeAliasDef(value) => { sb.to_id(db, InFile { value, file_id})?.into() },
+                    ast::ImplBlock(value) => { sb.to_id(db, InFile { value, file_id})?.into() },
                     _ => return None,
                 }
             };
             Some(res)
         })?;
-        let &id = sb.child_by_source(parent.into())[keys::TYPE_PARAM].get(&src)?;
-        Some(TypeParam { id })
+        sb.child_by_source(db, parent.into())[keys::TYPE_PARAM].get(&src).copied()
     }
 }
 
@@ -324,7 +244,8 @@ impl ToId for ast::Module {
     type ID = ModuleId;
 
     fn to_id<DB: HirDatabase>(
-        sb: &mut SourceBinder<'_, DB>,
+        db: &DB,
+        sb: &mut SourceBinder,
         src: InFile<ast::Module>,
     ) -> Option<ModuleId> {
         {
@@ -333,7 +254,7 @@ impl ToId for ast::Module {
                 .as_ref()
                 .map(|it| it.syntax())
                 .cloned()
-                .ancestors_with_macros(sb.db)
+                .ancestors_with_macros(db)
                 .skip(1)
                 .find_map(|it| {
                     let m = ast::Module::cast(it.value.clone())?;
@@ -341,15 +262,15 @@ impl ToId for ast::Module {
                 });
 
             let parent_module = match parent_declaration {
-                Some(parent_declaration) => sb.to_id(parent_declaration)?,
+                Some(parent_declaration) => sb.to_id(db, parent_declaration)?,
                 None => {
-                    let file_id = src.file_id.original_file(sb.db);
-                    sb.to_module_def(file_id)?.id
+                    let file_id = src.file_id.original_file(db);
+                    sb.to_module_def(db, file_id)?.id
                 }
             };
 
             let child_name = src.value.name()?.as_name();
-            let def_map = sb.db.crate_def_map(parent_module.krate);
+            let def_map = db.crate_def_map(parent_module.krate);
             let child_id = *def_map[parent_module.local_id].children.get(&child_name)?;
             Some(ModuleId { krate: parent_module.krate, local_id: child_id })
         }
diff --git a/crates/ra_hir_def/Cargo.toml b/crates/ra_hir_def/Cargo.toml
index 5053d0688..fa25cc4fb 100644
--- a/crates/ra_hir_def/Cargo.toml
+++ b/crates/ra_hir_def/Cargo.toml
@@ -14,7 +14,6 @@ rustc-hash = "1.1.0"
 either = "1.5.3"
 anymap = "0.12.1"
 drop_bomb = "0.1.4"
-itertools = "0.8.2"
 
 ra_arena = { path = "../ra_arena" }
 ra_db = { path = "../ra_db" }
diff --git a/crates/ra_ide/Cargo.toml b/crates/ra_ide/Cargo.toml
index 3407d2598..7625fc8c8 100644
--- a/crates/ra_ide/Cargo.toml
+++ b/crates/ra_ide/Cargo.toml
@@ -17,11 +17,7 @@ indexmap = "1.3.2"
 itertools = "0.8.2"
 join_to_string = "0.1.3"
 log = "0.4.8"
-rayon = "1.3.0"
-fst = { version = "0.3.5", default-features = false }
 rustc-hash = "1.1.0"
-unicase = "2.6.0"
-superslice = "1.0.0"
 rand = { version = "0.7.3", features = ["small_rng"] }
 once_cell = "1.3.1"
 
diff --git a/crates/ra_ide/src/call_hierarchy.rs b/crates/ra_ide/src/call_hierarchy.rs
index 51ac59a71..b00b6d431 100644
--- a/crates/ra_ide/src/call_hierarchy.rs
+++ b/crates/ra_ide/src/call_hierarchy.rs
@@ -2,13 +2,13 @@
 
 use indexmap::IndexMap;
 
-use hir::db::AstDatabase;
+use hir::Semantics;
 use ra_ide_db::RootDatabase;
 use ra_syntax::{ast, match_ast, AstNode, TextRange};
 
 use crate::{
-    call_info::FnCallNode, display::ToNav, expand::descend_into_macros, goto_definition,
-    references, FilePosition, NavigationTarget, RangeInfo,
+    call_info::FnCallNode, display::ToNav, goto_definition, references, FilePosition,
+    NavigationTarget, RangeInfo,
 };
 
 #[derive(Debug, Clone)]
@@ -38,30 +38,31 @@ pub(crate) fn call_hierarchy(
 }
 
 pub(crate) fn incoming_calls(db: &RootDatabase, position: FilePosition) -> Option<Vec<CallItem>> {
+    let sema = Semantics::new(db);
     // 1. Find all refs
     // 2. Loop through refs and determine unique fndef. This will become our `from: CallHierarchyItem,` in the reply.
     // 3. Add ranges relative to the start of the fndef.
     let refs = references::find_all_refs(db, position, None)?;
 
     let mut calls = CallLocations::default();
-    let mut sb = hir::SourceBinder::new(db);
 
     for reference in refs.info.references() {
         let file_id = reference.file_range.file_id;
-        let file = db.parse_or_expand(file_id.into())?;
+        let file = sema.parse(file_id);
+        let file = file.syntax();
         let token = file.token_at_offset(reference.file_range.range.start()).next()?;
-        let token = descend_into_macros(db, file_id, token);
-        let syntax = token.value.parent();
+        let token = sema.descend_into_macros(token);
+        let syntax = token.parent();
 
         // This target is the containing function
         if let Some(nav) = syntax.ancestors().find_map(|node| {
             match_ast! {
                 match node {
                     ast::FnDef(it) => {
-                        let def = sb.to_def(token.with_value(it))?;
-                        Some(def.to_nav(sb.db))
+                        let def = sema.to_def(&it)?;
+                        Some(def.to_nav(sema.db))
                     },
-                    _ => { None },
+                    _ => None,
                 }
             }
         }) {
@@ -74,11 +75,13 @@ pub(crate) fn incoming_calls(db: &RootDatabase, position: FilePosition) -> Optio
 }
 
 pub(crate) fn outgoing_calls(db: &RootDatabase, position: FilePosition) -> Option<Vec<CallItem>> {
+    let sema = Semantics::new(db);
     let file_id = position.file_id;
-    let file = db.parse_or_expand(file_id.into())?;
+    let file = sema.parse(file_id);
+    let file = file.syntax();
     let token = file.token_at_offset(position.offset).next()?;
-    let token = descend_into_macros(db, file_id, token);
-    let syntax = token.value.parent();
+    let token = sema.descend_into_macros(token);
+    let syntax = token.parent();
 
     let mut calls = CallLocations::default();
 
@@ -87,14 +90,11 @@ pub(crate) fn outgoing_calls(db: &RootDatabase, position: FilePosition) -> Optio
         .filter_map(|node| FnCallNode::with_node_exact(&node))
         .filter_map(|call_node| {
             let name_ref = call_node.name_ref()?;
-            let name_ref = token.with_value(name_ref.syntax());
-
-            let analyzer = hir::SourceAnalyzer::new(db, name_ref, None);
 
             if let Some(func_target) = match &call_node {
                 FnCallNode::CallExpr(expr) => {
                     //FIXME: Type::as_callable is broken
-                    let callable_def = analyzer.type_of(db, &expr.expr()?)?.as_callable()?;
+                    let callable_def = sema.type_of_expr(&expr.expr()?)?.as_callable()?;
                     match callable_def {
                         hir::CallableDef::FunctionId(it) => {
                             let fn_def: hir::Function = it.into();
@@ -105,15 +105,15 @@ pub(crate) fn outgoing_calls(db: &RootDatabase, position: FilePosition) -> Optio
                     }
                 }
                 FnCallNode::MethodCallExpr(expr) => {
-                    let function = analyzer.resolve_method_call(&expr)?;
+                    let function = sema.resolve_method_call(&expr)?;
                     Some(function.to_nav(db))
                 }
-                FnCallNode::MacroCallExpr(expr) => {
-                    let macro_def = analyzer.resolve_macro_call(db, name_ref.with_value(&expr))?;
+                FnCallNode::MacroCallExpr(macro_call) => {
+                    let macro_def = sema.resolve_macro_call(&macro_call)?;
                     Some(macro_def.to_nav(db))
                 }
             } {
-                Some((func_target, name_ref.value.text_range()))
+                Some((func_target, name_ref.syntax().text_range()))
             } else {
                 None
             }
diff --git a/crates/ra_ide/src/call_info.rs b/crates/ra_ide/src/call_info.rs
index 7c6322cb4..9a1fc0d35 100644
--- a/crates/ra_ide/src/call_info.rs
+++ b/crates/ra_ide/src/call_info.rs
@@ -1,5 +1,5 @@
 //! FIXME: write short doc here
-use hir::db::AstDatabase;
+use hir::Semantics;
 use ra_ide_db::RootDatabase;
 use ra_syntax::{
     ast::{self, ArgListOwner},
@@ -7,24 +7,23 @@ use ra_syntax::{
 };
 use test_utils::tested_by;
 
-use crate::{expand::descend_into_macros, CallInfo, FilePosition, FunctionSignature};
+use crate::{CallInfo, FilePosition, FunctionSignature};
 
 /// Computes parameter information for the given call expression.
 pub(crate) fn call_info(db: &RootDatabase, position: FilePosition) -> Option<CallInfo> {
-    let file = db.parse_or_expand(position.file_id.into())?;
+    let sema = Semantics::new(db);
+    let file = sema.parse(position.file_id);
+    let file = file.syntax();
     let token = file.token_at_offset(position.offset).next()?;
-    let token = descend_into_macros(db, position.file_id, token);
+    let token = sema.descend_into_macros(token);
 
     // Find the calling expression and it's NameRef
-    let calling_node = FnCallNode::with_node(&token.value.parent())?;
-    let name_ref = calling_node.name_ref()?;
-    let name_ref = token.with_value(name_ref.syntax());
+    let calling_node = FnCallNode::with_node(&token.parent())?;
 
-    let analyzer = hir::SourceAnalyzer::new(db, name_ref, None);
     let (mut call_info, has_self) = match &calling_node {
-        FnCallNode::CallExpr(expr) => {
+        FnCallNode::CallExpr(call) => {
             //FIXME: Type::as_callable is broken
-            let callable_def = analyzer.type_of(db, &expr.expr()?)?.as_callable()?;
+            let callable_def = sema.type_of_expr(&call.expr()?)?.as_callable()?;
             match callable_def {
                 hir::CallableDef::FunctionId(it) => {
                     let fn_def = it.into();
@@ -36,12 +35,12 @@ pub(crate) fn call_info(db: &RootDatabase, position: FilePosition) -> Option<Cal
                 }
             }
         }
-        FnCallNode::MethodCallExpr(expr) => {
-            let function = analyzer.resolve_method_call(&expr)?;
+        FnCallNode::MethodCallExpr(method_call) => {
+            let function = sema.resolve_method_call(&method_call)?;
             (CallInfo::with_fn(db, function), function.has_self_param(db))
         }
-        FnCallNode::MacroCallExpr(expr) => {
-            let macro_def = analyzer.resolve_macro_call(db, name_ref.with_value(&expr))?;
+        FnCallNode::MacroCallExpr(macro_call) => {
+            let macro_def = sema.resolve_macro_call(&macro_call)?;
             (CallInfo::with_macro(db, macro_def)?, false)
         }
     };
diff --git a/crates/ra_ide/src/completion.rs b/crates/ra_ide/src/completion.rs
index 4bdc6ba23..c378c2c62 100644
--- a/crates/ra_ide/src/completion.rs
+++ b/crates/ra_ide/src/completion.rs
@@ -17,7 +17,6 @@ mod complete_postfix;
 mod complete_macro_in_item_position;
 mod complete_trait_impl;
 
-use ra_db::SourceDatabase;
 use ra_ide_db::RootDatabase;
 
 #[cfg(test)]
@@ -57,8 +56,7 @@ pub use crate::completion::completion_item::{
 /// identifier prefix/fuzzy match should be done higher in the stack, together
 /// with ordering of completions (currently this is done by the client).
 pub(crate) fn completions(db: &RootDatabase, position: FilePosition) -> Option<Completions> {
-    let original_parse = db.parse(position.file_id);
-    let ctx = CompletionContext::new(db, &original_parse, position)?;
+    let ctx = CompletionContext::new(db, position)?;
 
     let mut acc = Completions::default();
 
diff --git a/crates/ra_ide/src/completion/complete_dot.rs b/crates/ra_ide/src/completion/complete_dot.rs
index 2ca78c927..a6e0158b2 100644
--- a/crates/ra_ide/src/completion/complete_dot.rs
+++ b/crates/ra_ide/src/completion/complete_dot.rs
@@ -16,7 +16,7 @@ pub(super) fn complete_dot(acc: &mut Completions, ctx: &CompletionContext) {
         _ => return,
     };
 
-    let receiver_ty = match ctx.analyzer.type_of(ctx.db, &dot_receiver) {
+    let receiver_ty = match ctx.sema.type_of_expr(&dot_receiver) {
         Some(ty) => ty,
         _ => return,
     };
@@ -55,7 +55,7 @@ fn complete_fields(acc: &mut Completions, ctx: &CompletionContext, receiver: &Ty
 fn complete_methods(acc: &mut Completions, ctx: &CompletionContext, receiver: &Type) {
     if let Some(krate) = ctx.module.map(|it| it.krate()) {
         let mut seen_methods = FxHashSet::default();
-        let traits_in_scope = ctx.analyzer.traits_in_scope(ctx.db);
+        let traits_in_scope = ctx.scope().traits_in_scope();
         receiver.iterate_method_candidates(ctx.db, krate, &traits_in_scope, None, |_ty, func| {
             if func.has_self_param(ctx.db) && seen_methods.insert(func.name(ctx.db)) {
                 acc.add_function(ctx, func);
diff --git a/crates/ra_ide/src/completion/complete_macro_in_item_position.rs b/crates/ra_ide/src/completion/complete_macro_in_item_position.rs
index faadd1e3f..1866d9e6c 100644
--- a/crates/ra_ide/src/completion/complete_macro_in_item_position.rs
+++ b/crates/ra_ide/src/completion/complete_macro_in_item_position.rs
@@ -5,7 +5,7 @@ use crate::completion::{CompletionContext, Completions};
 pub(super) fn complete_macro_in_item_position(acc: &mut Completions, ctx: &CompletionContext) {
     // Show only macros in top level.
     if ctx.is_new_item {
-        ctx.analyzer.process_all_names(ctx.db, &mut |name, res| {
+        ctx.scope().process_all_names(&mut |name, res| {
             if let hir::ScopeDef::MacroDef(mac) = res {
                 acc.add_macro(ctx, Some(name.to_string()), mac);
             }
diff --git a/crates/ra_ide/src/completion/complete_path.rs b/crates/ra_ide/src/completion/complete_path.rs
index 2d7f09a6c..c626e90cc 100644
--- a/crates/ra_ide/src/completion/complete_path.rs
+++ b/crates/ra_ide/src/completion/complete_path.rs
@@ -11,7 +11,7 @@ pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) {
         Some(path) => path.clone(),
         _ => return,
     };
-    let def = match ctx.analyzer.resolve_hir_path(ctx.db, &path) {
+    let def = match ctx.scope().resolve_hir_path(&path) {
         Some(PathResolution::Def(def)) => def,
         _ => return,
     };
@@ -49,7 +49,7 @@ pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) {
             // FIXME: complete T::AssocType
             let krate = ctx.module.map(|m| m.krate());
             if let Some(krate) = krate {
-                let traits_in_scope = ctx.analyzer.traits_in_scope(ctx.db);
+                let traits_in_scope = ctx.scope().traits_in_scope();
                 ty.iterate_path_candidates(ctx.db, krate, &traits_in_scope, None, |_ty, item| {
                     match item {
                         hir::AssocItem::Function(func) => {
diff --git a/crates/ra_ide/src/completion/complete_pattern.rs b/crates/ra_ide/src/completion/complete_pattern.rs
index fd03b1c40..c2c6ca002 100644
--- a/crates/ra_ide/src/completion/complete_pattern.rs
+++ b/crates/ra_ide/src/completion/complete_pattern.rs
@@ -9,7 +9,7 @@ pub(super) fn complete_pattern(acc: &mut Completions, ctx: &CompletionContext) {
     }
     // FIXME: ideally, we should look at the type we are matching against and
     // suggest variants + auto-imports
-    ctx.analyzer.process_all_names(ctx.db, &mut |name, res| {
+    ctx.scope().process_all_names(&mut |name, res| {
         let def = match &res {
             hir::ScopeDef::ModuleDef(def) => def,
             _ => return,
diff --git a/crates/ra_ide/src/completion/complete_postfix.rs b/crates/ra_ide/src/completion/complete_postfix.rs
index 5470dc291..8a74f993a 100644
--- a/crates/ra_ide/src/completion/complete_postfix.rs
+++ b/crates/ra_ide/src/completion/complete_postfix.rs
@@ -29,7 +29,7 @@ pub(super) fn complete_postfix(acc: &mut Completions, ctx: &CompletionContext) {
         dot_receiver.syntax().text().to_string()
     };
 
-    let receiver_ty = match ctx.analyzer.type_of(ctx.db, &dot_receiver) {
+    let receiver_ty = match ctx.sema.type_of_expr(&dot_receiver) {
         Some(it) => it,
         None => return,
     };
diff --git a/crates/ra_ide/src/completion/complete_record_literal.rs b/crates/ra_ide/src/completion/complete_record_literal.rs
index 577c394d2..f98353d76 100644
--- a/crates/ra_ide/src/completion/complete_record_literal.rs
+++ b/crates/ra_ide/src/completion/complete_record_literal.rs
@@ -5,10 +5,7 @@ use crate::completion::{CompletionContext, Completions};
 /// Complete fields in fields literals.
 pub(super) fn complete_record_literal(acc: &mut Completions, ctx: &CompletionContext) {