112 files changed, 4407 insertions, 3938 deletions
diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index ed9191c49..7f4e75341 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -116,9 +116,9 @@ jobs:
    - run: npm ci
      working-directory: ./editors/code
-    - run: npm audit || { sleep 10 && npm audit; } || { sleep 30 && npm audit; }
+#    - run: npm audit || { sleep 10 && npm audit; } || { sleep 30 && npm audit; }
-      if: runner.os == 'Linux'
+#      if: runner.os == 'Linux'
-      working-directory: ./editors/code
+#      working-directory: ./editors/code
    - run: npm run lint
      working-directory: ./editors/code
diff --git a/Cargo.lock b/Cargo.lock
index 9e0d0714a..61ae8157a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -52,17 +52,6 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cff77d8686867eceff3105329d4698d96c2391c176d5d03adc90c7389162b5b8"
 [[package]]
-name = "atty"
-version = "0.2.14"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d9b39be18770d11421cdb1b9947a45dd3f37e93092cbf377614828a319d5fee8"
-dependencies = [
- "hermit-abi",
- "libc",
- "winapi 0.3.9",
-]
-[[package]]
 name = "autocfg"
 version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -196,18 +185,6 @@ dependencies = [
 ]
 [[package]]
-name = "clicolors-control"
-version = "1.0.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "90082ee5dcdd64dc4e9e0d37fbf3ee325419e39c0092191e0393df65518f741e"
-dependencies = [
- "atty",
- "lazy_static",
- "libc",
- "winapi 0.3.9",
-]
-[[package]]
 name = "cloudabi"
 version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -218,11 +195,10 @@ dependencies = [
 [[package]]
 name = "console"
-version = "0.10.3"
+version = "0.11.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2586208b33573b7f76ccfbe5adb076394c88deaf81b84d7213969805b0a952a7"
+checksum = "8c0994e656bba7b922d8dd1245db90672ffb701e684e45be58f20719d69abc5a"
 dependencies = [
- "clicolors-control",
 "encode_unicode",
 "lazy_static",
 "libc",
@@ -352,6 +328,15 @@ dependencies = [
 ]
 [[package]]
+name = "expect"
+version = "0.1.0"
+dependencies = [
+ "difference",
+ "once_cell",
+ "stdx",
+]
+[[package]]
 name = "filetime"
 version = "0.2.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -544,9 +529,9 @@ dependencies = [
 [[package]]
 name = "insta"
-version = "0.16.0"
+version = "0.16.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8386e795fb3927131ea4cede203c529a333652eb6dc4ff29616b832b27e9b096"
+checksum = "617e921abc813f96a3b00958c079e7bf1e2db998f8a04f1546dd967373a418ee"
 dependencies = [
 "console",
 "difference",
@@ -1134,6 +1119,7 @@ name = "ra_ide"
 version = "0.1.0"
 dependencies = [
 "either",
+ "expect",
 "indexmap",
 "insta",
 "itertools",
@@ -1262,6 +1248,7 @@ dependencies = [
 "ra_syntax",
 "ra_text_edit",
 "rustc-hash",
+ "test_utils",
 ]
 [[package]]
@@ -1464,15 +1451,18 @@ dependencies = [
 "ra_hir_def",
 "ra_hir_ty",
 "ra_ide",
+ "ra_ide_db",
 "ra_mbe",
 "ra_proc_macro_srv",
 "ra_prof",
 "ra_project_model",
+ "ra_ssr",
 "ra_syntax",
 "ra_text_edit",
 "ra_toolchain",
 "ra_tt",
 "rand",
+ "rayon",
 "rustc-hash",
 "serde",
 "serde_json",
diff --git a/Cargo.toml b/Cargo.toml
index 5278b5a16..189f4ea2b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -24,6 +24,8 @@ opt-level = 0
 opt-level = 0
 [profile.release.package.salsa-macros]
 opt-level = 0
+[profile.release.package.tracing-attributes]
+opt-level = 0
 [profile.release.package.xtask]
 opt-level = 0
diff --git a/crates/expect/Cargo.toml b/crates/expect/Cargo.toml
new file mode 100644
index 000000000..caee43106
--- /dev/null
+++ b/crates/expect/Cargo.toml
@@ -0,0 +1,10 @@
+[package]
+name = "expect"
+version = "0.1.0"
+authors = ["rust-analyzer developers"]
+edition = "2018"
+[dependencies]
+once_cell = "1"
+difference = "2"
+stdx = { path = "../stdx" }
diff --git a/crates/expect/src/lib.rs b/crates/expect/src/lib.rs
new file mode 100644
index 000000000..a5e26fade
--- /dev/null
+++ b/crates/expect/src/lib.rs
@@ -0,0 +1,348 @@
+//! Snapshot testing library, see
+//! https://github.com/rust-analyzer/rust-analyzer/pull/5101
+use std::{
+    collections::HashMap,
+    env, fmt, fs, mem,
+    ops::Range,
+    panic,
+    path::{Path, PathBuf},
+    sync::Mutex,
+};
+use difference::Changeset;
+use once_cell::sync::Lazy;
+use stdx::{lines_with_ends, trim_indent};
+const HELP: &str = "
+You can update all `expect![[]]` tests by running:
+    env UPDATE_EXPECT=1 cargo test
+To update a single test, place the cursor on `expect` token and use `run` feature of rust-analyzer.
+";
+fn update_expect() -> bool {
+    env::var("UPDATE_EXPECT").is_ok()
+}
+/// expect![[r#"inline snapshot"#]]
+#[macro_export]
+macro_rules! expect {
+    [[$data:literal]] => {$crate::Expect {
+        position: $crate::Position {
+            file: file!(),
+            line: line!(),
+            column: column!(),
+        },
+        data: $data,
+    }};
+    [[]] => { $crate::expect![[""]] };
+}
+/// expect_file!["/crates/foo/test_data/bar.html"]
+#[macro_export]
+macro_rules! expect_file {
+    [$path:literal] => {$crate::ExpectFile { path: $path }};
+}
+#[derive(Debug)]
+pub struct Expect {
+    pub position: Position,
+    pub data: &'static str,
+}
+#[derive(Debug)]
+pub struct ExpectFile {
+    pub path: &'static str,
+}
+#[derive(Debug)]
+pub struct Position {
+    pub file: &'static str,
+    pub line: u32,
+    pub column: u32,
+}
+impl fmt::Display for Position {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}:{}:{}", self.file, self.line, self.column)
+    }
+}
+impl Expect {
+    pub fn assert_eq(&self, actual: &str) {
+        let trimmed = self.trimmed();
+        if &trimmed == actual {
+            return;
+        }
+        Runtime::fail_expect(self, &trimmed, actual);
+    }
+    pub fn assert_debug_eq(&self, actual: &impl fmt::Debug) {
+        let actual = format!("{:#?}\n", actual);
+        self.assert_eq(&actual)
+    }
+    fn trimmed(&self) -> String {
+        if !self.data.contains('\n') {
+            return self.data.to_string();
+        }
+        trim_indent(self.data)
+    }
+    fn locate(&self, file: &str) -> Location {
+        let mut target_line = None;
+        let mut line_start = 0;
+        for (i, line) in lines_with_ends(file).enumerate() {
+            if i == self.position.line as usize - 1 {
+                let pat = "expect![[";
+                let offset = line.find(pat).unwrap();
+                let literal_start = line_start + offset + pat.len();
+                let indent = line.chars().take_while(|&it| it == ' ').count();
+                target_line = Some((literal_start, indent));
+                break;
+            }
+            line_start += line.len();
+        }
+        let (literal_start, line_indent) = target_line.unwrap();
+        let literal_length =
+            file[literal_start..].find("]]").expect("Couldn't find matching `]]` for `expect![[`.");
+        let literal_range = literal_start..literal_start + literal_length;
+        Location { line_indent, literal_range }
+    }
+}
+impl ExpectFile {
+    pub fn assert_eq(&self, actual: &str) {
+        let expected = self.read();
+        if actual == expected {
+            return;
+        }
+        Runtime::fail_file(self, &expected, actual);
+    }
+    fn read(&self) -> String {
+        fs::read_to_string(self.abs_path()).unwrap_or_default().replace("\r\n", "\n")
+    }
+    fn write(&self, contents: &str) {
+        fs::write(self.abs_path(), contents).unwrap()
+    }
+    fn abs_path(&self) -> PathBuf {
+        workspace_root().join(self.path)
+    }
+}
+#[derive(Default)]
+struct Runtime {
+    help_printed: bool,
+    per_file: HashMap<&'static str, FileRuntime>,
+}
+static RT: Lazy<Mutex<Runtime>> = Lazy::new(Default::default);
+impl Runtime {
+    fn fail_expect(expect: &Expect, expected: &str, actual: &str) {
+        let mut rt = RT.lock().unwrap_or_else(|poisoned| poisoned.into_inner());
+        if update_expect() {
+            println!("\x1b[1m\x1b[92mupdating\x1b[0m: {}", expect.position);
+            rt.per_file
+                .entry(expect.position.file)
+                .or_insert_with(|| FileRuntime::new(expect))
+                .update(expect, actual);
+            return;
+        }
+        rt.panic(expect.position.to_string(), expected, actual);
+    }
+    fn fail_file(expect: &ExpectFile, expected: &str, actual: &str) {
+        let mut rt = RT.lock().unwrap_or_else(|poisoned| poisoned.into_inner());
+        if update_expect() {
+            println!("\x1b[1m\x1b[92mupdating\x1b[0m: {}", expect.path);
+            expect.write(actual);
+            return;
+        }
+        rt.panic(expect.path.to_string(), expected, actual);
+    }
+    fn panic(&mut self, position: String, expected: &str, actual: &str) {
+        let print_help = !mem::replace(&mut self.help_printed, true);
+        let help = if print_help { HELP } else { "" };
+        let diff = Changeset::new(actual, expected, "\n");
+        println!(
+            "\n
+\x1b[1m\x1b[91merror\x1b[97m: expect test failed\x1b[0m
+   \x1b[1m\x1b[34m-->\x1b[0m {}
+{}
+\x1b[1mExpect\x1b[0m:
+----
+{}
+----
+\x1b[1mActual\x1b[0m:
+----
+{}
+----
+\x1b[1mDiff\x1b[0m:
+----
+{}
+----
+",
+            position, help, expected, actual, diff
+        );
+        // Use resume_unwind instead of panic!() to prevent a backtrace, which is unnecessary noise.
+        panic::resume_unwind(Box::new(()));
+    }
+}
+struct FileRuntime {
+    path: PathBuf,
+    original_text: String,
+    patchwork: Patchwork,
+}
+impl FileRuntime {
+    fn new(expect: &Expect) -> FileRuntime {
+        let path = workspace_root().join(expect.position.file);
+        let original_text = fs::read_to_string(&path).unwrap();
+        let patchwork = Patchwork::new(original_text.clone());
+        FileRuntime { path, original_text, patchwork }
+    }
+    fn update(&mut self, expect: &Expect, actual: &str) {
+        let loc = expect.locate(&self.original_text);
+        let patch = format_patch(loc.line_indent.clone(), actual);
+        self.patchwork.patch(loc.literal_range, &patch);
+        fs::write(&self.path, &self.patchwork.text).unwrap()
+    }
+}
+#[derive(Debug)]
+struct Location {
+    line_indent: usize,
+    literal_range: Range<usize>,
+}
+#[derive(Debug)]
+struct Patchwork {
+    text: String,
+    indels: Vec<(Range<usize>, usize)>,
+}
+impl Patchwork {
+    fn new(text: String) -> Patchwork {
+        Patchwork { text, indels: Vec::new() }
+    }
+    fn patch(&mut self, mut range: Range<usize>, patch: &str) {
+        self.indels.push((range.clone(), patch.len()));
+        self.indels.sort_by_key(|(delete, _insert)| delete.start);
+        let (delete, insert) = self
+            .indels
+            .iter()
+            .take_while(|(delete, _)| delete.start < range.start)
+            .map(|(delete, insert)| (delete.end - delete.start, insert))
+            .fold((0usize, 0usize), |(x1, y1), (x2, y2)| (x1 + x2, y1 + y2));
+        for pos in &mut [&mut range.start, &mut range.end] {
+            **pos -= delete;
+            **pos += insert;
+        }
+        self.text.replace_range(range, &patch);
+    }
+}
+fn format_patch(line_indent: usize, patch: &str) -> String {
+    let mut max_hashes = 0;
+    let mut cur_hashes = 0;
+    for byte in patch.bytes() {
+        if byte != b'#' {
+            cur_hashes = 0;
+            continue;
+        }
+        cur_hashes += 1;
+        max_hashes = max_hashes.max(cur_hashes);
+    }
+    let hashes = &"#".repeat(max_hashes + 1);
+    let indent = &" ".repeat(line_indent);
+    let is_multiline = patch.contains('\n');
+    let mut buf = String::new();
+    buf.push('r');
+    buf.push_str(hashes);
+    buf.push('"');
+    if is_multiline {
+        buf.push('\n');
+    }
+    let mut final_newline = false;
+    for line in lines_with_ends(patch) {
+        if is_multiline {
+            buf.push_str(indent);
+            buf.push_str("    ");
+        }
+        buf.push_str(line);
+        final_newline = line.ends_with('\n');
+    }
+    if final_newline {
+        buf.push_str(indent);
+    }
+    buf.push('"');
+    buf.push_str(hashes);
+    buf
+}
+fn workspace_root() -> PathBuf {
+    Path::new(
+        &env::var("CARGO_MANIFEST_DIR").unwrap_or_else(|_| env!("CARGO_MANIFEST_DIR").to_owned()),
+    )
+    .ancestors()
+    .nth(2)
+    .unwrap()
+    .to_path_buf()
+}
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn test_format_patch() {
+        let patch = format_patch(0, "hello\nworld\n");
+        expect![[r##"
+            r#"
+                hello
+                world
+            "#"##]]
+        .assert_eq(&patch);
+        let patch = format_patch(4, "single line");
+        expect![[r##"r#"single line"#"##]].assert_eq(&patch);
+    }
+    #[test]
+    fn test_patchwork() {
+        let mut patchwork = Patchwork::new("one two three".to_string());
+        patchwork.patch(4..7, "zwei");
+        patchwork.patch(0..3, "один");
+        patchwork.patch(8..13, "3");
+        expect![[r#"
+            Patchwork {
+                text: "один zwei 3",
+                indels: [
+                    (
+                        0..3,
+                        8,
+                    ),
+                    (
+                        4..7,
+                        4,
+                    ),
+                    (
+                        8..13,
+                        1,
+                    ),
+                ],
+            }
+        "#]]
+        .assert_debug_eq(&patchwork);
+    }
+}
diff --git a/crates/flycheck/src/lib.rs b/crates/flycheck/src/lib.rs
index 1023d3040..844b093d4 100644
--- a/crates/flycheck/src/lib.rs
+++ b/crates/flycheck/src/lib.rs
@@ -132,6 +132,7 @@ impl FlycheckActor {
                    self.cancel_check_process();
                    let mut command = self.check_command();
+                    log::info!("restart flycheck {:?}", command);
                    command.stdout(Stdio::piped()).stderr(Stdio::null()).stdin(Stdio::null());
                    if let Ok(child) = command.spawn().map(JodChild) {
                        self.cargo_handle = Some(CargoHandle::spawn(child));
diff --git a/crates/ra_assists/src/assist_context.rs b/crates/ra_assists/src/assist_context.rs
index ee614de72..3640bb4d2 100644
--- a/crates/ra_assists/src/assist_context.rs
+++ b/crates/ra_assists/src/assist_context.rs
@@ -55,7 +55,6 @@ use crate::{
 pub(crate) struct AssistContext<'a> {
    pub(crate) config: &'a AssistConfig,
    pub(crate) sema: Semantics<'a, RootDatabase>,
-    pub(crate) db: &'a RootDatabase,
    pub(crate) frange: FileRange,
    source_file: SourceFile,
 }
@@ -67,8 +66,11 @@ impl<'a> AssistContext<'a> {
        frange: FileRange,
    ) -> AssistContext<'a> {
        let source_file = sema.parse(frange.file_id);
-        let db = sema.db;
+        AssistContext { config, sema, frange, source_file }
-        AssistContext { config, sema, db, frange, source_file }
+    }
+    pub(crate) fn db(&self) -> &RootDatabase {
+        self.sema.db
    }
    // NB, this ignores active selection.
diff --git a/crates/ra_assists/src/ast_transform.rs b/crates/ra_assists/src/ast_transform.rs
index 00fa95b6c..01adb834c 100644
--- a/crates/ra_assists/src/ast_transform.rs
+++ b/crates/ra_assists/src/ast_transform.rs
@@ -2,7 +2,6 @@
 use rustc_hash::FxHashMap;
 use hir::{HirDisplay, PathResolution, SemanticsScope};
-use ra_ide_db::RootDatabase;
 use ra_syntax::{
    algo::SyntaxRewriter,
    ast::{self, AstNode},
@@ -32,14 +31,14 @@ impl<'a> AstTransform<'a> for NullTransformer {
 }
 pub struct SubstituteTypeParams<'a> {
-    source_scope: &'a SemanticsScope<'a, RootDatabase>,
+    source_scope: &'a SemanticsScope<'a>,
    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>,
+        source_scope: &'a SemanticsScope<'a>,
        // FIXME: there's implicit invariant that `trait_` and  `source_scope` match...
        trait_: hir::Trait,
        impl_def: ast::ImplDef,
@@ -126,16 +125,13 @@ impl<'a> AstTransform<'a> for SubstituteTypeParams<'a> {
 }
 pub struct QualifyPaths<'a> {
-    target_scope: &'a SemanticsScope<'a, RootDatabase>,
+    target_scope: &'a SemanticsScope<'a>,
-    source_scope: &'a SemanticsScope<'a, RootDatabase>,
+    source_scope: &'a SemanticsScope<'a>,
    previous: Box<dyn AstTransform<'a> + 'a>,
 }
 impl<'a> QualifyPaths<'a> {
-    pub fn new(
+    pub fn new(target_scope: &'a SemanticsScope<'a>, source_scope: &'a SemanticsScope<'a>) -> Self {
-        target_scope: &'a SemanticsScope<'a, RootDatabase>,
-        source_scope: &'a SemanticsScope<'a, RootDatabase>,
-    ) -> Self {
        Self { target_scope, source_scope, previous: Box::new(NullTransformer) }
    }
@@ -156,7 +152,7 @@ impl<'a> QualifyPaths<'a> {
        let resolution = self.source_scope.resolve_hir_path(&hir_path?)?;
        match resolution {
            PathResolution::Def(def) => {
-                let found_path = from.find_use_path(self.source_scope.db, def)?;
+                let found_path = from.find_use_path(self.source_scope.db.upcast(), def)?;
                let mut path = path_to_ast(found_path);
                let type_args = p
diff --git a/crates/ra_assists/src/handlers/add_explicit_type.rs b/crates/ra_assists/src/handlers/add_explicit_type.rs
index 90b06a625..11df922a2 100644
--- a/crates/ra_assists/src/handlers/add_explicit_type.rs
+++ b/crates/ra_assists/src/handlers/add_explicit_type.rs
@@ -57,7 +57,7 @@ pub(crate) fn add_explicit_type(acc: &mut Assists, ctx: &AssistContext) -> Optio
        return None;
    }
-    let inferred_type = ty.display_source_code(ctx.db, module.into()).ok()?;
+    let inferred_type = ty.display_source_code(ctx.db(), module.into()).ok()?;
    acc.add(
        AssistId("add_explicit_type"),
        format!("Insert explicit type `{}`", inferred_type),
diff --git a/crates/ra_assists/src/handlers/add_function.rs b/crates/ra_assists/src/handlers/add_function.rs
index 1cfbd75aa..fc4e82309 100644
--- a/crates/ra_assists/src/handlers/add_function.rs
+++ b/crates/ra_assists/src/handlers/add_function.rs
@@ -117,7 +117,7 @@ impl FunctionBuilder {
        let mut file = ctx.frange.file_id;
        let target = match &target_module {
            Some(target_module) => {
-                let module_source = target_module.definition_source(ctx.db);
+                let module_source = target_module.definition_source(ctx.db());
                let (in_file, target) = next_space_for_fn_in_module(ctx.sema.db, &module_source)?;
                file = in_file;
                target
@@ -269,7 +269,7 @@ fn fn_arg_type(
        return None;
    }
-    if let Ok(rendered) = ty.display_source_code(ctx.db, target_module.into()) {
+    if let Ok(rendered) = ty.display_source_code(ctx.db(), target_module.into()) {
        Some(rendered)
    } else {
        None
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 abacd4065..77e092f62 100644
--- a/crates/ra_assists/src/handlers/add_missing_impl_members.rs
+++ b/crates/ra_assists/src/handlers/add_missing_impl_members.rs
@@ -128,9 +128,9 @@ fn add_missing_impl_members_inner(
    let missing_items = get_missing_assoc_items(&ctx.sema, &impl_def)
        .iter()
        .map(|i| match i {
-            hir::AssocItem::Function(i) => ast::AssocItem::FnDef(i.source(ctx.db).value),
+            hir::AssocItem::Function(i) => ast::AssocItem::FnDef(i.source(ctx.db()).value),
-            hir::AssocItem::TypeAlias(i) => ast::AssocItem::TypeAliasDef(i.source(ctx.db).value),
+            hir::AssocItem::TypeAlias(i) => ast::AssocItem::TypeAliasDef(i.source(ctx.db()).value),
-            hir::AssocItem::Const(i) => ast::AssocItem::ConstDef(i.source(ctx.db).value),
+            hir::AssocItem::Const(i) => ast::AssocItem::ConstDef(i.source(ctx.db()).value),
        })
        .filter(|t| def_name(&t).is_some())
        .filter(|t| match t {
diff --git a/crates/ra_assists/src/handlers/add_new.rs b/crates/ra_assists/src/handlers/add_new.rs
index 837aa8377..e41b2aa06 100644
--- a/crates/ra_assists/src/handlers/add_new.rs
+++ b/crates/ra_assists/src/handlers/add_new.rs
@@ -122,7 +122,7 @@ fn generate_impl_text(strukt: &ast::StructDef, code: &str) -> String {
 // FIXME: change the new fn checking to a more semantic approach when that's more
 // viable (e.g. we process proc macros, etc)
 fn find_struct_impl(ctx: &AssistContext, strukt: &ast::StructDef) -> Option<Option<ast::ImplDef>> {
-    let db = ctx.db;
+    let db = ctx.db();
    let module = strukt.syntax().ancestors().find(|node| {
        ast::Module::can_cast(node.kind()) || ast::SourceFile::can_cast(node.kind())
    })?;
diff --git a/crates/ra_assists/src/handlers/auto_import.rs b/crates/ra_assists/src/handlers/auto_import.rs
index d1cafa7d9..7b6499a08 100644
--- a/crates/ra_assists/src/handlers/auto_import.rs
+++ b/crates/ra_assists/src/handlers/auto_import.rs
@@ -5,7 +5,7 @@ use hir::{
    AsAssocItem, AssocItemContainer, ModPath, Module, ModuleDef, PathResolution, Semantics, Trait,
    Type,
 };
-use ra_ide_db::{imports_locator::ImportsLocator, RootDatabase};
+use ra_ide_db::{imports_locator, RootDatabase};
 use ra_prof::profile;
 use ra_syntax::{
    ast::{self, AstNode},
@@ -35,8 +35,8 @@ use crate::{utils::insert_use_statement, AssistContext, AssistId, Assists, Group
 // # pub mod std { pub mod collections { pub struct HashMap { } } }
 // ```
 pub(crate) fn auto_import(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
-    let auto_import_assets = AutoImportAssets::new(&ctx)?;
+    let auto_import_assets = AutoImportAssets::new(ctx)?;
-    let proposed_imports = auto_import_assets.search_for_imports(ctx.db);
+    let proposed_imports = auto_import_assets.search_for_imports(ctx);
    if proposed_imports.is_empty() {
        return None;
    }
@@ -127,11 +127,11 @@ impl AutoImportAssets {
        GroupLabel(name)
    }
-    fn search_for_imports(&self, db: &RootDatabase) -> BTreeSet<ModPath> {
+    fn search_for_imports(&self, ctx: &AssistContext) -> BTreeSet<ModPath> {
        let _p = profile("auto_import::search_for_imports");
+        let db = ctx.db();
        let current_crate = self.module_with_name_to_import.krate();
-        ImportsLocator::new(db, current_crate)
+        imports_locator::find_imports(&ctx.sema, current_crate, &self.get_search_query())
-            .find_imports(&self.get_search_query())
            .into_iter()
            .filter_map(|candidate| match &self.import_candidate {
                ImportCandidate::TraitAssocItem(assoc_item_type, _) => {
diff --git a/crates/ra_assists/src/handlers/extract_struct_from_enum_variant.rs b/crates/ra_assists/src/handlers/extract_struct_from_enum_variant.rs
index 43b4584b4..ca19cf198 100644
--- a/crates/ra_assists/src/handlers/extract_struct_from_enum_variant.rs
+++ b/crates/ra_assists/src/handlers/extract_struct_from_enum_variant.rs
@@ -37,15 +37,15 @@ pub(crate) fn extract_struct_from_enum_variant(
    };
    let variant_name = variant.name()?.to_string();
    let variant_hir = ctx.sema.to_def(&variant)?;
-    if existing_struct_def(ctx.db, &variant_name, &variant_hir) {
+    if existing_struct_def(ctx.db(), &variant_name, &variant_hir) {
        return None;
    }
    let enum_ast = variant.parent_enum();
    let visibility = enum_ast.visibility();
    let enum_hir = ctx.sema.to_def(&enum_ast)?;
-    let variant_hir_name = variant_hir.name(ctx.db);
+    let variant_hir_name = variant_hir.name(ctx.db());
    let enum_module_def = ModuleDef::from(enum_hir);
-    let current_module = enum_hir.module(ctx.db);
+    let current_module = enum_hir.module(ctx.db());
    let target = variant.syntax().text_range();
    acc.add(
        AssistId("extract_struct_from_enum_variant"),
@@ -53,7 +53,7 @@ pub(crate) fn extract_struct_from_enum_variant(
        target,
        |builder| {
            let definition = Definition::ModuleDef(ModuleDef::EnumVariant(variant_hir));
-            let res = definition.find_usages(&ctx.db, None);
+            let res = definition.find_usages(&ctx.sema, None);
            let start_offset = variant.parent_enum().syntax().text_range().start();
            let mut visited_modules_set = FxHashSet::default();
            visited_modules_set.insert(current_module);
@@ -101,7 +101,7 @@ fn insert_import(
    enum_module_def: &ModuleDef,
    variant_hir_name: &Name,
 ) -> Option<()> {
-    let db = ctx.db;
+    let db = ctx.db();
    let mod_path = module.find_use_path(db, enum_module_def.clone());
    if let Some(mut mod_path) = mod_path {
        mod_path.segments.pop();
diff --git a/crates/ra_assists/src/handlers/fill_match_arms.rs b/crates/ra_assists/src/handlers/fill_match_arms.rs
index 64270c86f..5b1235682 100644
--- a/crates/ra_assists/src/handlers/fill_match_arms.rs
+++ b/crates/ra_assists/src/handlers/fill_match_arms.rs
@@ -51,11 +51,11 @@ pub(crate) fn fill_match_arms(acc: &mut Assists, ctx: &AssistContext) -> Option<
    let module = ctx.sema.scope(expr.syntax()).module()?;
    let missing_arms: Vec<MatchArm> = if let Some(enum_def) = resolve_enum_def(&ctx.sema, &expr) {
-        let variants = enum_def.variants(ctx.db);
+        let variants = enum_def.variants(ctx.db());
        let mut variants = variants
            .into_iter()
-            .filter_map(|variant| build_pat(ctx.db, module, variant))
+            .filter_map(|variant| build_pat(ctx.db(), module, variant))
            .filter(|variant_pat| is_variant_missing(&mut arms, variant_pat))
            .map(|pat| make::match_arm(iter::once(pat), make::expr_empty_block()))
            .collect::<Vec<_>>();
@@ -84,11 +84,11 @@ pub(crate) fn fill_match_arms(acc: &mut Assists, ctx: &AssistContext) -> Option<
        // where each tuple represents a proposed match arm.
        enum_defs
            .into_iter()
-            .map(|enum_def| enum_def.variants(ctx.db))
+            .map(|enum_def| enum_def.variants(ctx.db()))
            .multi_cartesian_product()
            .map(|variants| {
                let patterns =
-                    variants.into_iter().filter_map(|variant| build_pat(ctx.db, module, variant));
+                    variants.into_iter().filter_map(|variant| build_pat(ctx.db(), module, variant));
                ast::Pat::from(make::tuple_pat(patterns))
            })
            .filter(|variant_pat| is_variant_missing(&mut arms, variant_pat))
diff --git a/crates/ra_assists/src/handlers/fix_visibility.rs b/crates/ra_assists/src/handlers/fix_visibility.rs
index 19d4dac5e..c0f57c329 100644
--- a/crates/ra_assists/src/handlers/fix_visibility.rs
+++ b/crates/ra_assists/src/handlers/fix_visibility.rs
@@ -41,14 +41,14 @@ fn add_vis_to_referenced_module_def(acc: &mut Assists, ctx: &AssistContext) -> O
    };
    let current_module = ctx.sema.scope(&path.syntax()).module()?;
-    let target_module = def.module(ctx.db)?;
+    let target_module = def.module(ctx.db())?;
-    let vis = target_module.visibility_of(ctx.db, &def)?;
+    let vis = target_module.visibility_of(ctx.db(), &def)?;
-    if vis.is_visible_from(ctx.db, current_module.into()) {
+    if vis.is_visible_from(ctx.db(), current_module.into()) {
        return None;
    };
-    let (offset, target, target_file, target_name) = target_data_for_def(ctx.db, def)?;
+    let (offset, target, target_file, target_name) = target_data_for_def(ctx.db(), def)?;
    let missing_visibility =
        if current_module.krate() == target_module.krate() { "pub(crate)" } else { "pub" };
@@ -72,16 +72,16 @@ fn add_vis_to_referenced_record_field(acc: &mut Assists, ctx: &AssistContext) ->
    let (record_field_def, _) = ctx.sema.resolve_record_field(&record_field)?;
    let current_module = ctx.sema.scope(record_field.syntax()).module()?;
-    let visibility = record_field_def.visibility(ctx.db);
+    let visibility = record_field_def.visibility(ctx.db());
-    if visibility.is_visible_from(ctx.db, current_module.into()) {
+    if visibility.is_visible_from(ctx.db(), current_module.into()) {
        return None;
    }
-    let parent = record_field_def.parent_def(ctx.db);
+    let parent = record_field_def.parent_def(ctx.db());
-    let parent_name = parent.name(ctx.db);
+    let parent_name = parent.name(ctx.db());
-    let target_module = parent.module(ctx.db);
+    let target_module = parent.module(ctx.db());
-    let in_file_source = record_field_def.source(ctx.db);
+    let in_file_source = record_field_def.source(ctx.db());
    let (offset, target) = match in_file_source.value {
        hir::FieldSource::Named(it) => {
            let s = it.syntax();
@@ -95,9 +95,9 @@ fn add_vis_to_referenced_record_field(acc: &mut Assists, ctx: &AssistContext) ->
    let missing_visibility =
        if current_module.krate() == target_module.krate() { "pub(crate)" } else { "pub" };
-    let target_file = in_file_source.file_id.original_file(ctx.db);
+    let target_file = in_file_source.file_id.original_file(ctx.db());
-    let target_name = record_field_def.name(ctx.db);
+    let target_name = record_field_def.name(ctx.db());
    let assist_label =
        format!("Change visibility of {}.{} to {}", parent_name, target_name, missing_visibility);
diff --git a/crates/ra_assists/src/handlers/inline_local_variable.rs b/crates/ra_assists/src/handlers/inline_local_variable.rs
index d26e68847..259839535 100644
--- a/crates/ra_assists/src/handlers/inline_local_variable.rs
+++ b/crates/ra_assists/src/handlers/inline_local_variable.rs
@@ -44,7 +44,7 @@ pub(crate) fn inline_local_variable(acc: &mut Assists, ctx: &AssistContext) -> O
    let def = ctx.sema.to_def(&bind_pat)?;
    let def = Definition::Local(def);
-    let refs = def.find_usages(ctx.db, None);
+    let refs = def.find_usages(&ctx.sema, None);
    if refs.is_empty() {
        mark::hit!(test_not_applicable_if_variable_unused);
        return None;
diff --git a/crates/ra_assists/src/handlers/reorder_fields.rs b/crates/ra_assists/src/handlers/reorder_fields.rs
index bc58ce5fe..b8cf30e7f 100644
--- a/crates/ra_assists/src/handlers/reorder_fields.rs
+++ b/crates/ra_assists/src/handlers/reorder_fields.rs
@@ -90,10 +90,10 @@ fn struct_definition(path: &ast::Path, sema: &Semantics<RootDatabase>) -> Option
 fn compute_fields_ranks(path: &ast::Path, ctx: &AssistContext) -> Option<FxHashMap<String, usize>> {
    Some(
        struct_definition(path, &ctx.sema)?
-            .fields(ctx.db)
+            .fields(ctx.db())
            .iter()
            .enumerate()
-            .map(|(idx, field)| (field.name(ctx.db).to_string(), idx))
+            .map(|(idx, field)| (field.name(ctx.db()).to_string(), idx))
            .collect(),
    )
 }
diff --git a/crates/ra_db/src/fixture.rs b/crates/ra_db/src/fixture.rs
index 4f4fb4494..209713987 100644
--- a/crates/ra_db/src/fixture.rs
+++ b/crates/ra_db/src/fixture.rs
@@ -149,15 +149,17 @@ fn with_files(
            let crate_id = crate_graph.add_crate_root(
                file_id,
                meta.edition,
-                Some(CrateName::new(&krate).unwrap()),
+                Some(krate.clone()),
                meta.cfg,
                meta.env,
                Default::default(),
            );
-            let prev = crates.insert(krate.clone(), crate_id);
+            let crate_name = CrateName::new(&krate).unwrap();
+            let prev = crates.insert(crate_name.clone(), crate_id);
            assert!(prev.is_none());
            for dep in meta.deps {
-                crate_deps.push((krate.clone(), dep))
+                let dep = CrateName::new(&dep).unwrap();
+                crate_deps.push((crate_name.clone(), dep))
            }
        } else if meta.path == "/main.rs" || meta.path == "/lib.rs" {
            assert!(default_crate_root.is_none());
diff --git a/crates/ra_db/src/input.rs b/crates/ra_db/src/input.rs
index 7f3660118..aaa492759 100644
--- a/crates/ra_db/src/input.rs
+++ b/crates/ra_db/src/input.rs
@@ -67,7 +67,7 @@ pub struct CrateGraph {
 #[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct CrateId(pub u32);
-#[derive(Debug, Clone, PartialEq, Eq)]
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct CrateName(SmolStr);
 impl CrateName {
@@ -94,6 +94,13 @@ impl fmt::Display for CrateName {
    }
 }
+impl ops::Deref for CrateName {
+    type Target = str;
+    fn deref(&self) -> &Self::Target {
+        &*self.0
+    }
+}
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
 pub struct ProcMacroId(pub u32);
@@ -117,7 +124,7 @@ pub struct CrateData {
    /// The name to display to the end user.
    /// This actual crate name can be different in a particular dependent crate
    /// or may even be missing for some cases, such as a dummy crate for the code snippet.
-    pub display_name: Option<CrateName>,
+    pub display_name: Option<String>,
    pub cfg_options: CfgOptions,
    pub env: Env,
    pub dependencies: Vec<Dependency>,
@@ -138,7 +145,7 @@ pub struct Env {
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct Dependency {
    pub crate_id: CrateId,
-    pub name: SmolStr,
+    pub name: CrateName,
 }
 impl CrateGraph {
@@ -146,7 +153,7 @@ impl CrateGraph {
        &mut self,
        file_id: FileId,
        edition: Edition,
-        display_name: Option<CrateName>,
+        display_name: Option<String>,
        cfg_options: CfgOptions,
        env: Env,
        proc_macro: Vec<(SmolStr, Arc<dyn ra_tt::TokenExpander>)>,
@@ -178,7 +185,7 @@ impl CrateGraph {
        if self.dfs_find(from, to, &mut FxHashSet::default()) {
            return Err(CyclicDependenciesError);
        }
-        self.arena.get_mut(&from).unwrap().add_dep(name.0, to);
+        self.arena.get_mut(&from).unwrap().add_dep(name, to);
        Ok(())
    }
@@ -190,6 +197,23 @@ impl CrateGraph {
        self.arena.keys().copied()
    }
+    /// Returns an iterator over all transitive dependencies of the given crate.
+    pub fn transitive_deps(&self, of: CrateId) -> impl Iterator<Item = CrateId> + '_ {
+        let mut worklist = vec![of];
+        let mut deps = FxHashSet::default();
+        while let Some(krate) = worklist.pop() {
+            if !deps.insert(krate) {
+                continue;
+            }
+            worklist.extend(self[krate].dependencies.iter().map(|dep| dep.crate_id));
+        }
+        deps.remove(&of);
+        deps.into_iter()
+    }
    // FIXME: this only finds one crate with the given root; we could have multiple
    pub fn crate_id_for_crate_root(&self, file_id: FileId) -> Option<CrateId> {
        let (&crate_id, _) =
@@ -247,7 +271,7 @@ impl CrateId {
 }
 impl CrateData {
-    fn add_dep(&mut self, name: SmolStr, crate_id: CrateId) {
+    fn add_dep(&mut self, name: CrateName, crate_id: CrateId) {
        self.dependencies.push(Dependency { name, crate_id })
    }
 }
@@ -429,7 +453,10 @@ mod tests {
            .is_ok());
        assert_eq!(
            graph[crate1].dependencies,
-            vec![Dependency { crate_id: crate2, name: "crate_name_with_dashes".into() }]
+            vec![Dependency {
+                crate_id: crate2,
+                name: CrateName::new("crate_name_with_dashes").unwrap()
+            }]
        );
    }
 }
diff --git a/crates/ra_db/src/lib.rs b/crates/ra_db/src/lib.rs
index 4a3ba57da..1ddacc1f6 100644
--- a/crates/ra_db/src/lib.rs
+++ b/crates/ra_db/src/lib.rs
@@ -80,7 +80,7 @@ pub struct FilePosition {
    pub offset: TextSize,
 }
-#[derive(Clone, Copy, Debug)]
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
 pub struct FileRange {
    pub file_id: FileId,
    pub range: TextRange,
diff --git a/crates/ra_hir/src/code_model.rs b/crates/ra_hir/src/code_model.rs
index e86077dd6..1b3525011 100644
--- a/crates/ra_hir/src/code_model.rs
+++ b/crates/ra_hir/src/code_model.rs
@@ -31,7 +31,7 @@ use hir_ty::{
    ApplicationTy, Canonical, GenericPredicate, InEnvironment, Substs, TraitEnvironment, Ty,
    TyDefId, TypeCtor,
 };
-use ra_db::{CrateId, CrateName, Edition, FileId};
+use ra_db::{CrateId, Edition, FileId};
 use ra_prof::profile;
 use ra_syntax::ast::{self, AttrsOwner, NameOwner};
 use rustc_hash::FxHashSet;
@@ -94,8 +94,8 @@ impl Crate {
        db.crate_graph()[self.id].edition
    }
-    pub fn display_name(self, db: &dyn HirDatabase) -> Option<CrateName> {
+    pub fn display_name(self, db: &dyn HirDatabase) -> Option<String> {
-        db.crate_graph()[self.id].display_name.as_ref().cloned()
+        db.crate_graph()[self.id].display_name.clone()
    }
    pub fn query_external_importables(
@@ -1053,12 +1053,14 @@ pub struct ImplDef {
 impl ImplDef {
    pub fn all_in_crate(db: &dyn HirDatabase, krate: Crate) -> Vec<ImplDef> {
-        let impls = db.impls_in_crate(krate.id);
+        let inherent = db.inherent_impls_in_crate(krate.id);
-        impls.all_impls().map(Self::from).collect()
+        let trait_ = db.trait_impls_in_crate(krate.id);
+        inherent.all_impls().chain(trait_.all_impls()).map(Self::from).collect()
    }
    pub fn for_trait(db: &dyn HirDatabase, krate: Crate, trait_: Trait) -> Vec<ImplDef> {
-        let impls = db.impls_in_crate(krate.id);
+        let impls = db.trait_impls_in_crate(krate.id);
-        impls.lookup_impl_defs_for_trait(trait_.id).map(Self::from).collect()
+        impls.for_trait(trait_.id).map(Self::from).collect()
    }
    pub fn target_trait(self, db: &dyn HirDatabase) -> Option<TypeRef> {
@@ -1187,7 +1189,7 @@ impl Type {
            None => return false,
        };
-        let canonical_ty = Canonical { value: self.ty.value.clone(), num_vars: 0 };
+        let canonical_ty = Canonical { value: self.ty.value.clone(), kinds: Arc::new([]) };
        method_resolution::implements_trait(
            &canonical_ty,
            db,
@@ -1211,7 +1213,7 @@ impl Type {
                self.ty.environment.clone(),
                hir_ty::Obligation::Trait(trait_ref),
            ),
-            num_vars: 0,
+            kinds: Arc::new([]),
        };
        db.trait_solve(self.krate, goal).is_some()
@@ -1286,7 +1288,7 @@ impl Type {
    pub fn autoderef<'a>(&'a self, db: &'a dyn HirDatabase) -> impl Iterator<Item = Type> + 'a {
        // There should be no inference vars in types passed here
        // FIXME check that?
-        let canonical = Canonical { value: self.ty.value.clone(), num_vars: 0 };
+        let canonical = Canonical { value: self.ty.value.clone(), kinds: Arc::new([]) };
        let environment = self.ty.environment.clone();
        let ty = InEnvironment { value: canonical, environment };
        autoderef(db, Some(self.krate), ty)
@@ -1303,10 +1305,10 @@ impl Type {
        mut callback: impl FnMut(AssocItem) -> Option<T>,
    ) -> Option<T> {
        for krate in self.ty.value.def_crates(db, krate.id)? {
-            let impls = db.impls_in_crate(krate);
+            let impls = db.inherent_impls_in_crate(krate);
-            for impl_def in impls.lookup_impl_defs(&self.ty.value) {
+            for impl_def in impls.for_self_ty(&self.ty.value) {
-                for &item in db.impl_data(impl_def).items.iter() {
+                for &item in db.impl_data(*impl_def).items.iter() {
                    if let Some(result) = callback(item.into()) {
                        return Some(result);
                    }
@@ -1327,7 +1329,7 @@ impl Type {
        // There should be no inference vars in types passed here
        // FIXME check that?
        // FIXME replace Unknown by bound vars here
-        let canonical = Canonical { value: self.ty.value.clone(), num_vars: 0 };
+        let canonical = Canonical { value: self.ty.value.clone(), kinds: Arc::new([]) };
        let env = self.ty.environment.clone();
        let krate = krate.id;
@@ -1358,7 +1360,7 @@ impl Type {
        // There should be no inference vars in types passed here
        // FIXME check that?
        // FIXME replace Unknown by bound vars here
-        let canonical = Canonical { value: self.ty.value.clone(), num_vars: 0 };
+        let canonical = Canonical { value: self.ty.value.clone(), kinds: Arc::new([]) };
        let env = self.ty.environment.clone();
        let krate = krate.id;
diff --git a/crates/ra_hir/src/db.rs b/crates/ra_hir/src/db.rs
index bb67952de..cb48ca065 100644
--- a/crates/ra_hir/src/db.rs
+++ b/crates/ra_hir/src/db.rs
@@ -16,10 +16,10 @@ pub use hir_expand::db::{
 pub use hir_ty::db::{
    AssociatedTyDataQuery, AssociatedTyValueQuery, CallableItemSignatureQuery, FieldTypesQuery,
    GenericDefaultsQuery, GenericPredicatesForParamQuery, GenericPredicatesQuery, HirDatabase,
-    HirDatabaseStorage, ImplDatumQuery, ImplSelfTyQuery, ImplTraitQuery, ImplsFromDepsQuery,
+    HirDatabaseStorage, ImplDatumQuery, ImplSelfTyQuery, ImplTraitQuery, InferQueryQuery,
-    ImplsInCrateQuery, InferQueryQuery, InternAssocTyValueQuery, InternChalkImplQuery,
+    InherentImplsInCrateQuery, InternAssocTyValueQuery, InternChalkImplQuery, InternTypeCtorQuery,
-    InternTypeCtorQuery, InternTypeParamIdQuery, ReturnTypeImplTraitsQuery, StructDatumQuery,
+    InternTypeParamIdQuery, ReturnTypeImplTraitsQuery, StructDatumQuery, TraitDatumQuery,
-    TraitDatumQuery, TraitSolveQuery, TyQuery, ValueTyQuery,
+    TraitImplsInCrateQuery, TraitImplsInDepsQuery, TraitSolveQuery, TyQuery, ValueTyQuery,
 };
 #[test]
diff --git a/crates/ra_hir/src/semantics.rs b/crates/ra_hir/src/semantics.rs
index 6a49c424a..3d78f71c1 100644
--- a/crates/ra_hir/src/semantics.rs
+++ b/crates/ra_hir/src/semantics.rs
@@ -83,6 +83,11 @@ impl PathResolution {
 /// Primary API to get semantic information, like types, from syntax trees.
 pub struct Semantics<'db, DB> {
    pub db: &'db DB,
+    imp: SemanticsImpl<'db>,
+}
+pub struct SemanticsImpl<'db> {
+    pub db: &'db dyn HirDatabase,
    s2d_cache: RefCell<SourceToDefCache>,
    cache: RefCell<FxHashMap<SyntaxNode, HirFileId>>,
 }
@@ -95,20 +100,180 @@ impl<DB> fmt::Debug for Semantics<'_, DB> {
 impl<'db, DB: HirDatabase> Semantics<'db, DB> {
    pub fn new(db: &DB) -> Semantics<DB> {
-        Semantics { db, s2d_cache: Default::default(), cache: Default::default() }
+        let impl_ = SemanticsImpl::new(db);
+        Semantics { db, imp: impl_ }
    }
    pub fn parse(&self, file_id: FileId) -> ast::SourceFile {
-        let tree = self.db.parse(file_id).tree();
+        self.imp.parse(file_id)
-        self.cache(tree.syntax().clone(), file_id.into());
-        tree
    }
    pub fn ast<T: AstDiagnostic + Diagnostic>(&self, d: &T) -> <T as AstDiagnostic>::AST {
        let file_id = d.source().file_id;
        let root = self.db.parse_or_expand(file_id).unwrap();
-        self.cache(root, file_id);
+        self.imp.cache(root, file_id);
-        d.ast(self.db)
+        d.ast(self.db.upcast())
+    }
+    pub fn expand(&self, macro_call: &ast::MacroCall) -> Option<SyntaxNode> {
+        self.imp.expand(macro_call)
+    }
+    pub fn expand_hypothetical(
+        &self,
+        actual_macro_call: &ast::MacroCall,
+        hypothetical_args: &ast::TokenTree,
+        token_to_map: SyntaxToken,
+    ) -> Option<(SyntaxNode, SyntaxToken)> {
+        self.imp.expand_hypothetical(actual_macro_call, hypothetical_args, token_to_map)
+    }
+    pub fn descend_into_macros(&self, token: SyntaxToken) -> SyntaxToken {
+        self.imp.descend_into_macros(token)
+    }
+    pub fn descend_node_at_offset<N: ast::AstNode>(
+        &self,
+        node: &SyntaxNode,
+        offset: TextSize,
+    ) -> Option<N> {
+        self.imp.descend_node_at_offset(node, offset).find_map(N::cast)
+    }
+    pub fn original_range(&self, node: &SyntaxNode) -> FileRange {
+        self.imp.original_range(node)
+    }
+    pub fn diagnostics_range(&self, diagnostics: &dyn Diagnostic) -> FileRange {
+        self.imp.diagnostics_range(diagnostics)
+    }
+    pub fn ancestors_with_macros(&self, node: SyntaxNode) -> impl Iterator<Item = SyntaxNode> + '_ {
+        self.imp.ancestors_with_macros(node)
+    }
+    pub fn ancestors_at_offset_with_macros(
+        &self,
+        node: &SyntaxNode,
+        offset: TextSize,
+    ) -> impl Iterator<Item = SyntaxNode> + '_ {
+        self.imp.ancestors_at_offset_with_macros(node, offset)
+    }
+    /// Find a AstNode by offset inside SyntaxNode, if it is inside *Macrofile*,
+    /// search up until it is of the target AstNode type
+    pub fn find_node_at_offset_with_macros<N: AstNode>(
+        &self,
+        node: &SyntaxNode,
+        offset: TextSize,
+    ) -> Option<N> {
+        self.imp.ancestors_at_offset_with_macros(node, offset).find_map(N::cast)
+    }
+    /// Find a AstNode by offset inside SyntaxNode, if it is inside *MacroCall*,
+    /// descend it and find again
+    pub fn find_node_at_offset_with_descend<N: AstNode>(
+        &self,
+        node: &SyntaxNode,
+        offset: TextSize,
+    ) -> Option<N> {
+        if let Some(it) = find_node_at_offset(&node, offset) {
+            return Some(it);
+        }
+        self.imp.descend_node_at_offset(node, offset).find_map(N::cast)
+    }
+    pub fn type_of_expr(&self, expr: &ast::Expr) -> Option<Type> {
+        self.imp.type_of_expr(expr)
+    }
+    pub fn type_of_pat(&self, pat: &ast::Pat) -> Option<Type> {
+        self.imp.type_of_pat(pat)
+    }
+    pub fn resolve_method_call(&self, call: &ast::MethodCallExpr) -> Option<Function> {
+        self.imp.resolve_method_call(call)
+    }
+    pub fn resolve_field(&self, field: &ast::FieldExpr) -> Option<Field> {
+        self.imp.resolve_field(field)
+    }
+    pub fn resolve_record_field(&self, field: &ast::RecordField) -> Option<(Field, Option<Local>)> {
+        self.imp.resolve_record_field(field)
+    }
+    pub fn resolve_record_field_pat(&self, field: &ast::RecordFieldPat) -> Option<Field> {
+        self.imp.resolve_record_field_pat(field)
+    }
+    pub fn resolve_macro_call(&self, macro_call: &ast::MacroCall) -> Option<MacroDef> {
+        self.imp.resolve_macro_call(macro_call)
+    }
+    pub fn resolve_path(&self, path: &ast::Path) -> Option<PathResolution> {
+        self.imp.resolve_path(path)
+    }
+    pub fn resolve_variant(&self, record_lit: ast::RecordLit) -> Option<VariantId> {
+        self.imp.resolve_variant(record_lit)
+    }
+    pub fn lower_path(&self, path: &ast::Path) -> Option<Path> {
+        self.imp.lower_path(path)
+    }
+    pub fn resolve_bind_pat_to_const(&self, pat: &ast::BindPat) -> Option<ModuleDef> {
+        self.imp.resolve_bind_pat_to_const(pat)
+    }
+    // FIXME: use this instead?
+    // pub fn resolve_name_ref(&self, name_ref: &ast::NameRef) -> Option<???>;
+    pub fn record_literal_missing_fields(&self, literal: &ast::RecordLit) -> Vec<(Field, Type)> {
+        self.imp.record_literal_missing_fields(literal)
+    }
+    pub fn record_pattern_missing_fields(&self, pattern: &ast::RecordPat) -> Vec<(Field, Type)> {
+        self.imp.record_pattern_missing_fields(pattern)
+    }
+    pub fn to_def<T: ToDef>(&self, src: &T) -> Option<T::Def> {
+        let src = self.imp.find_file(src.syntax().clone()).with_value(src).cloned();
+        T::to_def(&self.imp, src)
+    }
+    pub fn to_module_def(&self, file: FileId) -> Option<Module> {
+        self.imp.to_module_def(file)
+    }
+    pub fn scope(&self, node: &SyntaxNode) -> SemanticsScope<'db> {
+        self.imp.scope(node)
+    }
+    pub fn scope_at_offset(&self, node: &SyntaxNode, offset: TextSize) -> SemanticsScope<'db> {
+        self.imp.scope_at_offset(node, offset)
+    }
+    pub fn scope_for_def(&self, def: Trait) -> SemanticsScope<'db> {
+        self.imp.scope_for_def(def)
+    }
+    pub fn assert_contains_node(&self, node: &SyntaxNode) {
+        self.imp.assert_contains_node(node)
+    }
+}
+impl<'db> SemanticsImpl<'db> {
+    pub fn new(db: &'db dyn HirDatabase) -> Self {
+        Self { db, s2d_cache: Default::default(), cache: Default::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> {
@@ -130,9 +295,15 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
            self.find_file(actual_macro_call.syntax().clone()).with_value(actual_macro_call);
        let sa = self.analyze2(macro_call.map(|it| it.syntax()), None);
        let krate = sa.resolver.krate()?;
-        let macro_call_id = macro_call
+        let macro_call_id = macro_call.as_call_id(self.db.upcast(), krate, |path| {
-            .as_call_id(self.db, krate, |path| sa.resolver.resolve_path_as_macro(self.db, &path))?;
+            sa.resolver.resolve_path_as_macro(self.db.upcast(), &path)
-        hir_expand::db::expand_hypothetical(self.db, macro_call_id, hypothetical_args, token_to_map)
+        })?;
+        hir_expand::db::expand_hypothetical(
+            self.db.upcast(),
+            macro_call_id,
+            hypothetical_args,
+            token_to_map,
+        )
    }
    pub fn descend_into_macros(&self, token: SyntaxToken) -> SyntaxToken {
@@ -147,7 +318,7 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
                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())?;
+            let token = file_id.expansion_info(self.db.upcast())?.map_token_down(token.as_ref())?;
            self.cache(find_root(&token.value.parent()), token.file_id);
@@ -159,15 +330,16 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
        token.value
    }
-    pub fn descend_node_at_offset<N: ast::AstNode>(
+    pub fn descend_node_at_offset(
        &self,
        node: &SyntaxNode,
        offset: TextSize,
-    ) -> Option<N> {
+    ) -> impl Iterator<Item = SyntaxNode> + '_ {
        // Handle macro token cases
        node.token_at_offset(offset)
            .map(|token| self.descend_into_macros(token))
-            .find_map(|it| self.ancestors_with_macros(it.parent()).find_map(N::cast))
+            .map(|it| self.ancestors_with_macros(it.parent()))
+            .flatten()
    }
    pub fn original_range(&self, node: &SyntaxNode) -> FileRange {
@@ -184,7 +356,7 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
    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)
+        node.ancestors_with_macros(self.db.upcast()).map(|it| it.value)
    }
    pub fn ancestors_at_offset_with_macros(
@@ -197,29 +369,6 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
            .kmerge_by(|node1, node2| node1.text_range().len() < node2.text_range().len())
    }
-    /// Find a AstNode by offset inside SyntaxNode, if it is inside *Macrofile*,
-    /// search up until it is of the target AstNode type
-    pub fn find_node_at_offset_with_macros<N: AstNode>(
-        &self,
-        node: &SyntaxNode,
-        offset: TextSize,
-    ) -> Option<N> {
-        self.ancestors_at_offset_with_macros(node, offset).find_map(N::cast)
-    }
-    /// Find a AstNode by offset inside SyntaxNode, if it is inside *MacroCall*,
-    /// descend it and find again
-    pub fn find_node_at_offset_with_descend<N: AstNode>(
-        &self,
-        node: &SyntaxNode,
-        offset: TextSize,
-    ) -> Option<N> {
-        if let Some(it) = find_node_at_offset(&node, offset) {
-            return Some(it);
-        }
-        self.descend_node_at_offset(&node, offset)
-    }
    pub fn type_of_expr(&self, expr: &ast::Expr) -> Option<Type> {
        self.analyze(expr.syntax()).type_of(self.db, &expr)
    }
@@ -267,9 +416,6 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
        self.analyze(pat.syntax()).resolve_bind_pat_to_const(self.db, pat)
    }
-    // FIXME: use this instead?
-    // pub fn resolve_name_ref(&self, name_ref: &ast::NameRef) -> Option<???>;
    pub fn record_literal_missing_fields(&self, literal: &ast::RecordLit) -> Vec<(Field, Type)> {
        self.analyze(literal.syntax())
            .record_literal_missing_fields(self.db, literal)
@@ -282,11 +428,6 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
            .unwrap_or_default()
    }
-    pub fn to_def<T: ToDef>(&self, src: &T) -> Option<T::Def> {
-        let src = self.find_file(src.syntax().clone()).with_value(src).cloned();
-        T::to_def(self, src)
-    }
    fn with_ctx<F: FnOnce(&mut SourceToDefCtx) -> T, T>(&self, f: F) -> T {
        let mut cache = self.s2d_cache.borrow_mut();
        let mut ctx = SourceToDefCtx { db: self.db, cache: &mut *cache };
@@ -297,20 +438,20 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
        self.with_ctx(|ctx| ctx.file_to_def(file)).map(Module::from)
    }
-    pub fn scope(&self, node: &SyntaxNode) -> SemanticsScope<'db, DB> {
+    pub fn scope(&self, node: &SyntaxNode) -> SemanticsScope<'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: TextSize) -> SemanticsScope<'db, DB> {
+    pub fn scope_at_offset(&self, node: &SyntaxNode, offset: TextSize) -> SemanticsScope<'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> {
+    pub fn scope_for_def(&self, def: Trait) -> SemanticsScope<'db> {
-        let resolver = def.id.resolver(self.db);
+        let resolver = def.id.resolver(self.db.upcast());
        SemanticsScope { db: self.db, resolver }
    }
@@ -331,17 +472,17 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
            ChildContainer::DefWithBodyId(def) => {
                return SourceAnalyzer::new_for_body(self.db, def, src, offset)
            }
-            ChildContainer::TraitId(it) => it.resolver(self.db),
+            ChildContainer::TraitId(it) => it.resolver(self.db.upcast()),
-            ChildContainer::ImplId(it) => it.resolver(self.db),
+            ChildContainer::ImplId(it) => it.resolver(self.db.upcast()),
-            ChildContainer::ModuleId(it) => it.resolver(self.db),
+            ChildContainer::ModuleId(it) => it.resolver(self.db.upcast()),
-            ChildContainer::EnumId(it) => it.resolver(self.db),
+            ChildContainer::EnumId(it) => it.resolver(self.db.upcast()),
-            ChildContainer::VariantId(it) => it.resolver(self.db),
+            ChildContainer::VariantId(it) => it.resolver(self.db.upcast()),
-            ChildContainer::GenericDefId(it) => it.resolver(self.db),
+            ChildContainer::GenericDefId(it) => it.resolver(self.db.upcast()),
        };
        SourceAnalyzer::new_for_resolver(resolver, src)
    }
-    fn cache(&self, root_node: SyntaxNode, file_id: HirFileId) {
+    pub 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);
@@ -357,7 +498,7 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
        cache.get(root_node).copied()
    }
-    fn find_file(&self, node: SyntaxNode) -> InFile<SyntaxNode> {
+    pub 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!(
@@ -382,14 +523,14 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
 pub trait ToDef: AstNode + Clone {
    type Def;
-    fn to_def<DB: HirDatabase>(sema: &Semantics<DB>, src: InFile<Self>) -> Option<Self::Def>;
+    fn to_def(sema: &SemanticsImpl, src: InFile<Self>) -> Option<Self::Def>;
 }
 macro_rules! to_def_impls {
    ($(($def:path, $ast:path, $meth:ident)),* ,) => {$(
        impl ToDef for $ast {
            type Def = $def;
-            fn to_def<DB: HirDatabase>(sema: &Semantics<DB>, src: InFile<Self>) -> Option<Self::Def> {
+            fn to_def(sema: &SemanticsImpl, src: InFile<Self>) -> Option<Self::Def> {
                sema.with_ctx(|ctx| ctx.$meth(src)).map(<$def>::from)
            }
        }
@@ -419,12 +560,12 @@ fn find_root(node: &SyntaxNode) -> SyntaxNode {
    node.ancestors().last().unwrap()
 }
-pub struct SemanticsScope<'a, DB> {
+pub struct SemanticsScope<'a> {
-    pub db: &'a DB,
+    pub db: &'a dyn HirDatabase,
    resolver: Resolver,
 }
-impl<'a, DB: HirDatabase> SemanticsScope<'a, DB> {
+impl<'a> SemanticsScope<'a> {
    pub fn module(&self) -> Option<Module> {
        Some(Module { id: self.resolver.module()? })
    }
@@ -433,13 +574,13 @@ impl<'a, DB: HirDatabase> SemanticsScope<'a, DB> {
    // 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)
+        resolver.traits_in_scope(self.db.upcast())
    }
    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| {
+        resolver.process_all_names(self.db.upcast(), &mut |name, def| {
            let def = match def {
                resolver::ScopeDef::PerNs(it) => {
                    let items = ScopeDef::all_items(it);
diff --git a/crates/ra_hir_def/src/item_scope.rs b/crates/ra_hir_def/src/item_scope.rs
index 4d446c707..beeb98559 100644
--- a/crates/ra_hir_def/src/item_scope.rs
+++ b/crates/ra_hir_def/src/item_scope.rs
@@ -1,6 +1,8 @@
 //! Describes items defined or visible (ie, imported) in a certain scope.
 //! This is shared between modules and blocks.
+use std::collections::hash_map::Entry;
 use hir_expand::name::Name;
 use once_cell::sync::Lazy;
 use ra_db::CrateId;
@@ -27,7 +29,11 @@ pub struct PerNsGlobImports {
 #[derive(Debug, Default, PartialEq, Eq)]
 pub struct ItemScope {
-    visible: FxHashMap<Name, PerNs>,
+    types: FxHashMap<Name, (ModuleDefId, Visibility)>,
+    values: FxHashMap<Name, (ModuleDefId, Visibility)>,
+    macros: FxHashMap<Name, (MacroDefId, Visibility)>,
+    unresolved: FxHashSet<Name>,
    defs: Vec<ModuleDefId>,
    impls: Vec<ImplId>,
    /// Macros visible in current module in legacy textual scope
@@ -65,14 +71,16 @@ pub(crate) enum BuiltinShadowMode {
 /// Other methods will only resolve values, types and module scoped macros only.
 impl ItemScope {
    pub fn entries<'a>(&'a self) -> impl Iterator<Item = (&'a Name, PerNs)> + 'a {
-        //FIXME: shadowing
+        // FIXME: shadowing
-        self.visible.iter().map(|(n, def)| (n, *def))
+        let keys: FxHashSet<_> = self
-    }
+            .types
+            .keys()
-    pub fn entries_without_primitives<'a>(
+            .chain(self.values.keys())
-        &'a self,
+            .chain(self.macros.keys())
-    ) -> impl Iterator<Item = (&'a Name, PerNs)> + 'a {
+            .chain(self.unresolved.iter())
-        self.visible.iter().map(|(n, def)| (n, *def))
+            .collect();
+        keys.into_iter().map(move |name| (name, self.get(name)))
    }
    pub fn declarations(&self) -> impl Iterator<Item = ModuleDefId> + '_ {
@@ -91,7 +99,7 @@ impl ItemScope {
    /// Iterate over all module scoped macros
    pub(crate) fn macros<'a>(&'a self) -> impl Iterator<Item = (&'a Name, MacroDefId)> + 'a {
-        self.visible.iter().filter_map(|(name, def)| def.take_macros().map(|macro_| (name, macro_)))
+        self.entries().filter_map(|(name, def)| def.take_macros().map(|macro_| (name, macro_)))
    }
    /// Iterate over all legacy textual scoped macros visible at the end of the module
@@ -101,12 +109,16 @@ impl ItemScope {
    /// Get a name from current module scope, legacy macros are not included
    pub(crate) fn get(&self, name: &Name) -> PerNs {
-        self.visible.get(name).copied().unwrap_or_else(PerNs::none)
+        PerNs {
+            types: self.types.get(name).copied(),
+            values: self.values.get(name).copied(),
+            macros: self.macros.get(name).copied(),
+        }
    }
    pub(crate) fn name_of(&self, item: ItemInNs) -> Option<(&Name, Visibility)> {
-        for (name, per_ns) in &self.visible {
+        for (name, per_ns) in self.entries() {
-            if let Some(vis) = item.match_with(*per_ns) {
+            if let Some(vis) = item.match_with(per_ns) {
                return Some((name, vis));
            }
        }
@@ -114,8 +126,8 @@ impl ItemScope {
    }
    pub(crate) fn traits<'a>(&'a self) -> impl Iterator<Item = TraitId> + 'a {
-        self.visible.values().filter_map(|def| match def.take_types() {
+        self.types.values().filter_map(|(def, _)| match def {
-            Some(ModuleDefId::TraitId(t)) => Some(t),
+            ModuleDefId::TraitId(t) => Some(*t),
            _ => None,
        })
    }
@@ -138,21 +150,30 @@ impl ItemScope {
    pub(crate) fn push_res(&mut self, name: Name, def: PerNs) -> bool {
        let mut changed = false;
-        let existing = self.visible.entry(name).or_default();
-        if existing.types.is_none() && def.types.is_some() {
+        if let Some(types) = def.types {
-            existing.types = def.types;
+            self.types.entry(name.clone()).or_insert_with(|| {
-            changed = true;
+                changed = true;
+                types
+            });
        }
+        if let Some(values) = def.values {
-        if existing.values.is_none() && def.values.is_some() {
+            self.values.entry(name.clone()).or_insert_with(|| {
-            existing.values = def.values;
+                changed = true;
-            changed = true;
+                values
+            });
+        }
+        if let Some(macros) = def.macros {
+            self.macros.entry(name.clone()).or_insert_with(|| {
+                changed = true;
+                macros
+            });
        }
-        if existing.macros.is_none() && def.macros.is_some() {
+        if def.is_none() {
-            existing.macros = def.macros;
+            if self.unresolved.insert(name) {
-            changed = true;
+                changed = true;
+            }
        }
        changed
@@ -166,17 +187,17 @@ impl ItemScope {
        def_import_type: ImportType,
    ) -> bool {
        let mut changed = false;
-        let existing = self.visible.entry(lookup.1.clone()).or_default();
        macro_rules! check_changed {
            (
                $changed:ident,
-                ( $existing:ident / $def:ident ) . $field:ident,
+                ( $this:ident / $def:ident ) . $field:ident,
                $glob_imports:ident [ $lookup:ident ],
                $def_import_type:ident
-            ) => {
+            ) => {{
-                match ($existing.$field, $def.$field) {
+                let existing = $this.$field.entry($lookup.1.clone());
-                    (None, Some(_)) => {
+                match (existing, $def.$field) {
+                    (Entry::Vacant(entry), Some(_)) => {
                        match $def_import_type {
                            ImportType::Glob => {
                                $glob_imports.$field.insert($lookup.clone());
@@ -186,32 +207,42 @@ impl ItemScope {
                            }
                        }
-                        $existing.$field = $def.$field;
+                        if let Some(fld) = $def.$field {
+                            entry.insert(fld);
+                        }
                        $changed = true;
                    }
-                    (Some(_), Some(_))
+                    (Entry::Occupied(mut entry), Some(_))
                        if $glob_imports.$field.contains(&$lookup)
                            && matches!($def_import_type, ImportType::Named) =>
                    {
                        mark::hit!(import_shadowed);
                        $glob_imports.$field.remove(&$lookup);
-                        $existing.$field = $def.$field;
+                        if let Some(fld) = $def.$field {
+                            entry.insert(fld);
+                        }
                        $changed = true;
                    }
                    _ => {}
                }
-            };
+            }};
        }
-        check_changed!(changed, (existing / def).types, glob_imports[lookup], def_import_type);
+        check_changed!(changed, (self / def).types, glob_imports[lookup], def_import_type);
-        check_changed!(changed, (existing / def).values, glob_imports[lookup], def_import_type);
+        check_changed!(changed, (self / def).values, glob_imports[lookup], def_import_type);
-        check_changed!(changed, (existing / def).macros, glob_imports[lookup], def_import_type);
+        check_changed!(changed, (self / def).macros, glob_imports[lookup], def_import_type);
+        if def.is_none() {
+            if self.unresolved.insert(lookup.1) {
+                changed = true;
+            }
+        }
        changed
    }
    pub(crate) fn resolutions<'a>(&'a self) -> impl Iterator<Item = (Name, PerNs)> + 'a {
-        self.visible.iter().map(|(name, res)| (name.clone(), *res))
+        self.entries().map(|(name, res)| (name.clone(), res))
    }
    pub(crate) fn collect_legacy_macros(&self) -> FxHashMap<Name, MacroDefId> {
diff --git a/crates/ra_hir_def/src/item_tree/lower.rs b/crates/ra_hir_def/src/item_tree/lower.rs
index 5149dd141..06743d7fc 100644
--- a/crates/ra_hir_def/src/item_tree/lower.rs
+++ b/crates/ra_hir_def/src/item_tree/lower.rs
@@ -211,7 +211,7 @@ impl Ctx {
    fn lower_record_field(&mut self, field: &ast::RecordFieldDef) -> Option<Field> {
        let name = field.name()?.as_name();
        let visibility = self.lower_visibility(field);
-        let type_ref = self.lower_type_ref(&field.ascribed_type()?);
+        let type_ref = self.lower_type_ref_opt(field.ascribed_type());
        let res = Field { name, type_ref, visibility };
        Some(res)
    }
diff --git a/crates/ra_hir_def/src/resolver.rs b/crates/ra_hir_def/src/resolver.rs
index 15fdd9019..0bf51eb7b 100644
--- a/crates/ra_hir_def/src/resolver.rs
+++ b/crates/ra_hir_def/src/resolver.rs
@@ -511,11 +511,9 @@ impl Scope {
                    });
                }
            }
-            Scope::LocalItemsScope(body) => {
+            Scope::LocalItemsScope(body) => body.item_scope.entries().for_each(|(name, def)| {
-                body.item_scope.entries_without_primitives().for_each(|(name, def)| {
+                f(name.clone(), ScopeDef::PerNs(def));
-                    f(name.clone(), ScopeDef::PerNs(def));
+            }),
-                })
-            }
            Scope::GenericParams { params, def } => {
                for (local_id, param) in params.types.iter() {
                    if let Some(name) = &param.name {
diff --git a/crates/ra_hir_expand/src/builtin_derive.rs b/crates/ra_hir_expand/src/builtin_derive.rs
index 26b667b55..f2d664863 100644
--- a/crates/ra_hir_expand/src/builtin_derive.rs
+++ b/crates/ra_hir_expand/src/builtin_derive.rs
@@ -161,7 +161,7 @@ fn find_builtin_crate(db: &dyn AstDatabase, id: LazyMacroId) -> tt::TokenTree {
    // XXX
    //  All crates except core itself should have a dependency on core,
    //  We detect `core` by seeing whether it doesn't have such a dependency.
-    let tt = if cg[krate].dependencies.iter().any(|dep| dep.name == "core") {
+    let tt = if cg[krate].dependencies.iter().any(|dep| &*dep.name == "core") {
        quote! { core }
    } else {
        quote! { crate }
diff --git a/crates/ra_hir_expand/src/diagnostics.rs b/crates/ra_hir_expand/src/diagnostics.rs
index 99209c6e8..545cff9bd 100644
--- a/crates/ra_hir_expand/src/diagnostics.rs
+++ b/crates/ra_hir_expand/src/diagnostics.rs
@@ -28,7 +28,7 @@ pub trait Diagnostic: Any + Send + Sync + fmt::Debug + 'static {
 pub trait AstDiagnostic {
    type AST;
-    fn ast(&self, db: &impl AstDatabase) -> Self::AST;
+    fn ast(&self, db: &dyn AstDatabase) -> Self::AST;
 }
 impl dyn Diagnostic {
diff --git a/crates/ra_hir_expand/src/name.rs b/crates/ra_hir_expand/src/name.rs
index 1b0303685..969a2e5b8 100644
--- a/crates/ra_hir_expand/src/name.rs
+++ b/crates/ra_hir_expand/src/name.rs
@@ -117,7 +117,7 @@ impl AsName for ast::FieldKind {
 impl AsName for ra_db::Dependency {
    fn as_name(&self) -> Name {
-        Name::new_text(self.name.clone())
+        Name::new_text(SmolStr::new(&*self.name))
    }
 }
diff --git a/crates/ra_hir_ty/src/autoderef.rs b/crates/ra_hir_ty/src/autoderef.rs
index 1b0f84c5c..c727012c6 100644
--- a/crates/ra_hir_ty/src/autoderef.rs
+++ b/crates/ra_hir_ty/src/autoderef.rs
@@ -37,7 +37,7 @@ pub(crate) fn deref(
    ty: InEnvironment<&Canonical<Ty>>,
 ) -> Option<Canonical<Ty>> {
    if let Some(derefed) = ty.value.value.builtin_deref() {
-        Some(Canonical { value: derefed, num_vars: ty.value.num_vars })
+        Some(Canonical { value: derefed, kinds: ty.value.kinds.clone() })
    } else {
        deref_by_trait(db, krate, ty)
    }
@@ -68,8 +68,8 @@ fn deref_by_trait(
    // Check that the type implements Deref at all
    let trait_ref = TraitRef { trait_: deref_trait, substs: parameters.clone() };
-    let implements_goal = super::Canonical {
+    let implements_goal = Canonical {
-        num_vars: ty.value.num_vars,
+        kinds: ty.value.kinds.clone(),
        value: InEnvironment {
            value: Obligation::Trait(trait_ref),
            environment: ty.environment.clone(),
@@ -81,7 +81,7 @@ fn deref_by_trait(
    // Now do the assoc type projection
    let projection = super::traits::ProjectionPredicate {
-        ty: Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, ty.value.num_vars)),
+        ty: Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, ty.value.kinds.len())),
        projection_ty: super::ProjectionTy { associated_ty: target, parameters },
    };
@@ -89,7 +89,8 @@ fn deref_by_trait(
    let in_env = InEnvironment { value: obligation, environment: ty.environment };
-    let canonical = super::Canonical { num_vars: 1 + ty.value.num_vars, value: in_env };
+    let canonical =
+        Canonical::new(in_env, ty.value.kinds.iter().copied().chain(Some(super::TyKind::General)));
    let solution = db.trait_solve(krate, canonical)?;
@@ -110,7 +111,7 @@ fn deref_by_trait(
            // assumptions will be broken. We would need to properly introduce
            // new variables in that case
-            for i in 1..vars.0.num_vars {
+            for i in 1..vars.0.kinds.len() {
                if vars.0.value[i - 1] != Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, i - 1))
                {
                    warn!("complex solution for derefing {:?}: {:?}, ignoring", ty.value, solution);
@@ -119,7 +120,7 @@ fn deref_by_trait(
            }
            Some(Canonical {
                value: vars.0.value[vars.0.value.len() - 1].clone(),
-                num_vars: vars.0.num_vars,
+                kinds: vars.0.kinds.clone(),
            })
        }
        Solution::Ambig(_) => {
diff --git a/crates/ra_hir_ty/src/db.rs b/crates/ra_hir_ty/src/db.rs
index cad553273..dc06c0ee7 100644
--- a/crates/ra_hir_ty/src/db.rs
+++ b/crates/ra_hir_ty/src/db.rs
@@ -11,7 +11,7 @@ use ra_db::{impl_intern_key, salsa, CrateId, Upcast};
 use ra_prof::profile;
 use crate::{
-    method_resolution::CrateImplDefs,
+    method_resolution::{InherentImpls, TraitImpls},
    traits::{chalk, AssocTyValue, Impl},
    Binders, CallableDef, GenericPredicate, InferenceResult, OpaqueTyId, PolyFnSig,
    ReturnTypeImplTraits, TraitRef, Ty, TyDefId, TypeCtor, ValueTyDefId,
@@ -67,11 +67,14 @@ pub trait HirDatabase: DefDatabase + Upcast<dyn DefDatabase> {
    #[salsa::invoke(crate::lower::generic_defaults_query)]
    fn generic_defaults(&self, def: GenericDefId) -> Arc<[Binders<Ty>]>;
-    #[salsa::invoke(crate::method_resolution::CrateImplDefs::impls_in_crate_query)]
+    #[salsa::invoke(InherentImpls::inherent_impls_in_crate_query)]
-    fn impls_in_crate(&self, krate: CrateId) -> Arc<CrateImplDefs>;
+    fn inherent_impls_in_crate(&self, krate: CrateId) -> Arc<InherentImpls>;
-    #[salsa::invoke(crate::method_resolution::CrateImplDefs::impls_from_deps_query)]
+    #[salsa::invoke(TraitImpls::trait_impls_in_crate_query)]
-    fn impls_from_deps(&self, krate: CrateId) -> Arc<CrateImplDefs>;
+    fn trait_impls_in_crate(&self, krate: CrateId) -> Arc<TraitImpls>;
+    #[salsa::invoke(TraitImpls::trait_impls_in_deps_query)]
+    fn trait_impls_in_deps(&self, krate: CrateId) -> Arc<TraitImpls>;
    // Interned IDs for Chalk integration
    #[salsa::interned]
diff --git a/crates/ra_hir_ty/src/diagnostics.rs b/crates/ra_hir_ty/src/diagnostics.rs
index a59efb347..0289911de 100644
--- a/crates/ra_hir_ty/src/diagnostics.rs
+++ b/crates/ra_hir_ty/src/diagnostics.rs
@@ -32,7 +32,7 @@ impl Diagnostic for NoSuchField {
 impl AstDiagnostic for NoSuchField {
    type AST = ast::RecordField;
-    fn ast(&self, db: &impl AstDatabase) -> Self::AST {
+    fn ast(&self, db: &dyn AstDatabase) -> Self::AST {
        let root = db.parse_or_expand(self.source().file_id).unwrap();
        let node = self.source().value.to_node(&root);
        ast::RecordField::cast(node).unwrap()
@@ -65,7 +65,7 @@ impl Diagnostic for MissingFields {
 impl AstDiagnostic for MissingFields {
    type AST = ast::RecordFieldList;
-    fn ast(&self, db: &impl AstDatabase) -> Self::AST {
+    fn ast(&self, db: &dyn AstDatabase) -> Self::AST {
        let root = db.parse_or_expand(self.source().file_id).unwrap();
        let node = self.source().value.to_node(&root);
        ast::RecordFieldList::cast(node).unwrap()
@@ -135,7 +135,7 @@ impl Diagnostic for MissingOkInTailExpr {
 impl AstDiagnostic for MissingOkInTailExpr {
    type AST = ast::Expr;
-    fn ast(&self, db: &impl AstDatabase) -> Self::AST {
+    fn ast(&self, db: &dyn AstDatabase) -> Self::AST {
        let root = db.parse_or_expand(self.file).unwrap();
        let node = self.source().value.to_node(&root);
        ast::Expr::cast(node).unwrap()
@@ -163,7 +163,7 @@ impl Diagnostic for BreakOutsideOfLoop {
 impl AstDiagnostic for BreakOutsideOfLoop {
    type AST = ast::Expr;
-    fn ast(&self, db: &impl AstDatabase) -> Self::AST {
+    fn ast(&self, db: &dyn AstDatabase) -> Self::AST {
        let root = db.parse_or_expand(self.file).unwrap();
        let node = self.source().value.to_node(&root);
        ast::Expr::cast(node).unwrap()
@@ -191,7 +191,7 @@ impl Diagnostic for MissingUnsafe {
 impl AstDiagnostic for MissingUnsafe {
    type AST = ast::Expr;
-    fn ast(&self, db: &impl AstDatabase) -> Self::AST {
+    fn ast(&self, db: &dyn AstDatabase) -> Self::AST {
        let root = db.parse_or_expand(self.source().file_id).unwrap();
        let node = self.source().value.to_node(&root);
        ast::Expr::cast(node).unwrap()
diff --git a/crates/ra_hir_ty/src/infer/unify.rs b/crates/ra_hir_ty/src/infer/unify.rs
index 269495ca0..2e895d911 100644
--- a/crates/ra_hir_ty/src/infer/unify.rs
+++ b/crates/ra_hir_ty/src/infer/unify.rs
@@ -9,7 +9,7 @@ use test_utils::mark;
 use super::{InferenceContext, Obligation};
 use crate::{
    BoundVar, Canonical, DebruijnIndex, GenericPredicate, InEnvironment, InferTy, Substs, Ty,
-    TypeCtor, TypeWalk,
+    TyKind, TypeCtor, TypeWalk,
 };
 impl<'a> InferenceContext<'a> {
@@ -86,10 +86,20 @@ where
    }
    fn into_canonicalized<T>(self, result: T) -> Canonicalized<T> {
-        Canonicalized {
+        let kinds = self
-            value: Canonical { value: result, num_vars: self.free_vars.len() },
+            .free_vars
-            free_vars: self.free_vars,
+            .iter()
-        }
+            .map(|v| match v {
+                // mapping MaybeNeverTypeVar to the same kind as general ones
+                // should be fine, because as opposed to int or float type vars,
+                // they don't restrict what kind of type can go into them, they
+                // just affect fallback.
+                InferTy::TypeVar(_) | InferTy::MaybeNeverTypeVar(_) => TyKind::General,
+                InferTy::IntVar(_) => TyKind::Integer,
+                InferTy::FloatVar(_) => TyKind::Float,
+            })
+            .collect();
+        Canonicalized { value: Canonical { value: result, kinds }, free_vars: self.free_vars }
    }
    pub(crate) fn canonicalize_ty(mut self, ty: Ty) -> Canonicalized<Ty> {
@@ -131,26 +141,41 @@ impl<T> Canonicalized<T> {
        ty
    }
-    pub fn apply_solution(&self, ctx: &mut InferenceContext<'_>, solution: Canonical<Vec<Ty>>) {
+    pub fn apply_solution(&self, ctx: &mut InferenceContext<'_>, solution: Canonical<Substs>) {
        // the solution may contain new variables, which we need to convert to new inference vars
-        let new_vars = Substs((0..solution.num_vars).map(|_| ctx.table.new_type_var()).collect());
+        let new_vars = Substs(
+            solution
+                .kinds
+                .iter()
+                .map(|k| match k {
+                    TyKind::General => ctx.table.new_type_var(),
+                    TyKind::Integer => ctx.table.new_integer_var(),
+                    TyKind::Float => ctx.table.new_float_var(),
+                })
+                .collect(),
+        );
        for (i, ty) in solution.value.into_iter().enumerate() {
            let var = self.free_vars[i];
            // eagerly replace projections in the type; we may be getting types
            // e.g. from where clauses where this hasn't happened yet
-            let ty = ctx.normalize_associated_types_in(ty.subst_bound_vars(&new_vars));
+            let ty = ctx.normalize_associated_types_in(ty.clone().subst_bound_vars(&new_vars));
            ctx.table.unify(&Ty::Infer(var), &ty);
        }
    }
 }
-pub fn unify(ty1: &Canonical<Ty>, ty2: &Canonical<Ty>) -> Option<Substs> {
+pub fn unify(tys: &Canonical<(Ty, Ty)>) -> Option<Substs> {
    let mut table = InferenceTable::new();
-    let num_vars = ty1.num_vars.max(ty2.num_vars);
+    let vars = Substs(
-    let vars =
+        tys.kinds
-        Substs::builder(num_vars).fill(std::iter::repeat_with(|| table.new_type_var())).build();
+            .iter()
-    let ty1_with_vars = ty1.value.clone().subst_bound_vars(&vars);
+            // we always use type vars here because we want everything to
-    let ty2_with_vars = ty2.value.clone().subst_bound_vars(&vars);
+            // fallback to Unknown in the end (kind of hacky, as below)
+            .map(|_| table.new_type_var())
+            .collect(),
+    );
+    let ty1_with_vars = tys.value.0.clone().subst_bound_vars(&vars);
+    let ty2_with_vars = tys.value.1.clone().subst_bound_vars(&vars);
    if !table.unify(&ty1_with_vars, &ty2_with_vars) {
        return None;
    }
@@ -162,7 +187,7 @@ pub fn unify(ty1: &Canonical<Ty>, ty2: &Canonical<Ty>) -> Option<Substs> {
        }
    }
    Some(
-        Substs::builder(ty1.num_vars)
+        Substs::builder(tys.kinds.len())
            .fill(vars.iter().map(|v| table.resolve_ty_completely(v.clone())))
            .build(),
    )
diff --git a/crates/ra_hir_ty/src/lib.rs b/crates/ra_hir_ty/src/lib.rs
index c9513b752..7f3f5e771 100644
--- a/crates/ra_hir_ty/src/lib.rs
+++ b/crates/ra_hir_ty/src/lib.rs
@@ -662,13 +662,27 @@ impl TypeWalk for GenericPredicate {
 /// Basically a claim (currently not validated / checked) that the contained
 /// type / trait ref contains no inference variables; any inference variables it
-/// contained have been replaced by bound variables, and `num_vars` tells us how
+/// contained have been replaced by bound variables, and `kinds` tells us how
-/// many there are. This is used to erase irrelevant differences between types
+/// many there are and whether they were normal or float/int variables. This is
-/// before using them in queries.
+/// used to erase irrelevant differences between types before using them in
+/// queries.
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct Canonical<T> {
    pub value: T,
-    pub num_vars: usize,
+    pub kinds: Arc<[TyKind]>,
+}
+impl<T> Canonical<T> {
+    pub fn new(value: T, kinds: impl IntoIterator<Item = TyKind>) -> Self {
+        Self { value, kinds: kinds.into_iter().collect() }
+    }
+}
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
+pub enum TyKind {
+    General,
+    Integer,
+    Float,
 }
 /// A function signature as seen by type inference: Several parameter types and
diff --git a/crates/ra_hir_ty/src/method_resolution.rs b/crates/ra_hir_ty/src/method_resolution.rs
index c19519cf1..a45febbf7 100644
--- a/crates/ra_hir_ty/src/method_resolution.rs
+++ b/crates/ra_hir_ty/src/method_resolution.rs
@@ -2,7 +2,7 @@
 //! For details about how this works in rustc, see the method lookup page in the
 //! [rustc guide](https://rust-lang.github.io/rustc-guide/method-lookup.html)
 //! and the corresponding code mostly in librustc_typeck/check/method/probe.rs.
-use std::sync::Arc;
+use std::{iter, sync::Arc};
 use arrayvec::ArrayVec;
 use hir_def::{
@@ -17,7 +17,8 @@ use rustc_hash::{FxHashMap, FxHashSet};
 use super::Substs;
 use crate::{
    autoderef, db::HirDatabase, primitive::FloatBitness, utils::all_super_traits, ApplicationTy,
-    Canonical, DebruijnIndex, InEnvironment, TraitEnvironment, TraitRef, Ty, TypeCtor, TypeWalk,
+    Canonical, DebruijnIndex, InEnvironment, TraitEnvironment, TraitRef, Ty, TyKind, TypeCtor,
+    TypeWalk,
 };
 /// This is used as a key for indexing impls.
@@ -38,136 +39,131 @@ impl TyFingerprint {
    }
 }
-/// A queryable and mergeable collection of impls.
+/// Trait impls defined or available in some crate.
-#[derive(Debug, PartialEq, Eq)]
+#[derive(Debug, Eq, PartialEq)]
-pub struct CrateImplDefs {
+pub struct TraitImpls {
-    inherent_impls: FxHashMap<TyFingerprint, Vec<ImplId>>,
+    // If the `Option<TyFingerprint>` is `None`, the impl may apply to any self type.
-    impls_by_trait: FxHashMap<TraitId, FxHashMap<Option<TyFingerprint>, Vec<ImplId>>>,
+    map: FxHashMap<TraitId, FxHashMap<Option<TyFingerprint>, Vec<ImplId>>>,
 }
-impl CrateImplDefs {
+impl TraitImpls {
-    pub(crate) fn impls_in_crate_query(db: &dyn HirDatabase, krate: CrateId) -> Arc<CrateImplDefs> {
+    pub(crate) fn trait_impls_in_crate_query(db: &dyn HirDatabase, krate: CrateId) -> Arc<Self> {
-        let _p = profile("impls_in_crate_query");
+        let _p = profile("trait_impls_in_crate_query");
-        let mut res = CrateImplDefs {
+        let mut impls = Self { map: FxHashMap::default() };
-            inherent_impls: FxHashMap::default(),
-            impls_by_trait: FxHashMap::default(),
-        };
-        res.fill(db, krate);
-        Arc::new(res)
+        let crate_def_map = db.crate_def_map(krate);
+        for (_module_id, module_data) in crate_def_map.modules.iter() {
+            for impl_id in module_data.scope.impls() {
+                let target_trait = match db.impl_trait(impl_id) {
+                    Some(tr) => tr.value.trait_,
+                    None => continue,
+                };
+                let self_ty = db.impl_self_ty(impl_id);
+                let self_ty_fp = TyFingerprint::for_impl(&self_ty.value);
+                impls
+                    .map
+                    .entry(target_trait)
+                    .or_default()
+                    .entry(self_ty_fp)
+                    .or_default()
+                    .push(impl_id);
+            }
+        }
+        Arc::new(impls)
    }
-    /// Collects all impls from transitive dependencies of `krate` that may be used by `krate`.
+    pub(crate) fn trait_impls_in_deps_query(db: &dyn HirDatabase, krate: CrateId) -> Arc<Self> {
-    ///
+        let _p = profile("trait_impls_in_deps_query");
-    /// The full set of impls that can be used by `krate` is the returned map plus all the impls
-    /// from `krate` itself.
-    pub(crate) fn impls_from_deps_query(
-        db: &dyn HirDatabase,
-        krate: CrateId,
-    ) -> Arc<CrateImplDefs> {
-        let _p = profile("impls_from_deps_query");
        let crate_graph = db.crate_graph();
-        let mut res = CrateImplDefs {
+        let mut res = Self { map: FxHashMap::default() };
-            inherent_impls: FxHashMap::default(),
-            impls_by_trait: FxHashMap::default(),
-        };
-        // For each dependency, calculate `impls_from_deps` recursively, then add its own
+        for krate in crate_graph.transitive_deps(krate) {
-        // `impls_in_crate`.
+            res.merge(&db.trait_impls_in_crate(krate));
-        // As we might visit crates multiple times, `merge` has to deduplicate impls to avoid
-        // wasting memory.
-        for dep in &crate_graph[krate].dependencies {
-            res.merge(&db.impls_from_deps(dep.crate_id));
-            res.merge(&db.impls_in_crate(dep.crate_id));
        }
        Arc::new(res)
    }
-    fn fill(&mut self, db: &dyn HirDatabase, krate: CrateId) {
-        let crate_def_map = db.crate_def_map(krate);
-        for (_module_id, module_data) in crate_def_map.modules.iter() {
-            for impl_id in module_data.scope.impls() {
-                match db.impl_trait(impl_id) {
-                    Some(tr) => {
-                        let self_ty = db.impl_self_ty(impl_id);
-                        let self_ty_fp = TyFingerprint::for_impl(&self_ty.value);
-                        self.impls_by_trait
-                            .entry(tr.value.trait_)
-                            .or_default()
-                            .entry(self_ty_fp)
-                            .or_default()
-                            .push(impl_id);
-                    }
-                    None => {
-                        let self_ty = db.impl_self_ty(impl_id);
-                        if let Some(self_ty_fp) = TyFingerprint::for_impl(&self_ty.value) {
-                            self.inherent_impls.entry(self_ty_fp).or_default().push(impl_id);
-                        }
-                    }
-                }
-            }
-        }
-    }
    fn merge(&mut self, other: &Self) {
-        for (fp, impls) in &other.inherent_impls {
+        for (trait_, other_map) in &other.map {
-            let vec = self.inherent_impls.entry(*fp).or_default();
+            let map = self.map.entry(*trait_).or_default();
-            vec.extend(impls);
-            vec.sort();
-            vec.dedup();
-        }
-        for (trait_, other_map) in &other.impls_by_trait {
-            let map = self.impls_by_trait.entry(*trait_).or_default();
            for (fp, impls) in other_map {
                let vec = map.entry(*fp).or_default();
                vec.extend(impls);
-                vec.sort();
-                vec.dedup();
            }
        }
    }
-    pub fn lookup_impl_defs(&self, ty: &Ty) -> impl Iterator<Item = ImplId> + '_ {
+    /// Queries all impls of the given trait.
-        let fingerprint = TyFingerprint::for_impl(ty);
+    pub fn for_trait(&self, trait_: TraitId) -> impl Iterator<Item = ImplId> + '_ {
-        fingerprint.and_then(|f| self.inherent_impls.get(&f)).into_iter().flatten().copied()
+        self.map
-    }
+            .get(&trait_)
-    pub fn lookup_impl_defs_for_trait(&self, tr: TraitId) -> impl Iterator<Item = ImplId> + '_ {
-        self.impls_by_trait
-            .get(&tr)
            .into_iter()
-            .flat_map(|m| m.values().flat_map(|v| v.iter().copied()))
+            .flat_map(|map| map.values().flat_map(|v| v.iter().copied()))
    }
-    pub fn lookup_impl_defs_for_trait_and_ty(
+    /// Queries all impls of `trait_` that may apply to `self_ty`.
+    pub fn for_trait_and_self_ty(
        &self,
-        tr: TraitId,
+        trait_: TraitId,
-        fp: TyFingerprint,
+        self_ty: TyFingerprint,
    ) -> impl Iterator<Item = ImplId> + '_ {
-        self.impls_by_trait
+        self.map
-            .get(&tr)
+            .get(&trait_)
-            .and_then(|m| m.get(&Some(fp)))
            .into_iter()
-            .flatten()
+            .flat_map(move |map| map.get(&None).into_iter().chain(map.get(&Some(self_ty))))
-            .copied()
+            .flat_map(|v| v.iter().copied())
-            .chain(
+    }
-                self.impls_by_trait
-                    .get(&tr)
+    pub fn all_impls(&self) -> impl Iterator<Item = ImplId> + '_ {
-                    .and_then(|m| m.get(&None))
+        self.map.values().flat_map(|map| map.values().flat_map(|v| v.iter().copied()))
-                    .into_iter()
+    }
-                    .flatten()
+}
-                    .copied(),
-            )
+/// Inherent impls defined in some crate.
+///
+/// Inherent impls can only be defined in the crate that also defines the self type of the impl
+/// (note that some primitives are considered to be defined by both libcore and liballoc).
+///
+/// This makes inherent impl lookup easier than trait impl lookup since we only have to consider a
+/// single crate.
+#[derive(Debug, Eq, PartialEq)]
+pub struct InherentImpls {
+    map: FxHashMap<TyFingerprint, Vec<ImplId>>,
+}
+impl InherentImpls {
+    pub(crate) fn inherent_impls_in_crate_query(db: &dyn HirDatabase, krate: CrateId) -> Arc<Self> {
+        let mut map: FxHashMap<_, Vec<_>> = FxHashMap::default();
+        let crate_def_map = db.crate_def_map(krate);
+        for (_module_id, module_data) in crate_def_map.modules.iter() {
+            for impl_id in module_data.scope.impls() {
+                let data = db.impl_data(impl_id);
+                if data.target_trait.is_some() {
+                    continue;
+                }
+                let self_ty = db.impl_self_ty(impl_id);
+                if let Some(fp) = TyFingerprint::for_impl(&self_ty.value) {
+                    map.entry(fp).or_default().push(impl_id);
+                }
+            }
+        }
+        Arc::new(Self { map })
+    }
+    pub fn for_self_ty(&self, self_ty: &Ty) -> &[ImplId] {
+        match TyFingerprint::for_impl(self_ty) {
+            Some(fp) => self.map.get(&fp).map(|vec| vec.as_ref()).unwrap_or(&[]),
+            None => &[],
+        }
    }
-    pub fn all_impls<'a>(&'a self) -> impl Iterator<Item = ImplId> + 'a {
+    pub fn all_impls(&self) -> impl Iterator<Item = ImplId> + '_ {
-        self.inherent_impls
+        self.map.values().flat_map(|v| v.iter().copied())
-            .values()
-            .chain(self.impls_by_trait.values().flat_map(|m| m.values()))
-            .flatten()
-            .copied()
    }
 }
@@ -377,7 +373,7 @@ fn iterate_method_candidates_with_autoref(
        return true;
    }
    let refed = Canonical {
-        num_vars: deref_chain[0].num_vars,
+        kinds: deref_chain[0].kinds.clone(),
        value: Ty::apply_one(TypeCtor::Ref(Mutability::Shared), deref_chain[0].value.clone()),
    };
    if iterate_method_candidates_by_receiver(
@@ -393,7 +389,7 @@ fn iterate_method_candidates_with_autoref(
        return true;
    }
    let ref_muted = Canonical {
-        num_vars: deref_chain[0].num_vars,
+        kinds: deref_chain[0].kinds.clone(),
        value: Ty::apply_one(TypeCtor::Ref(Mutability::Mut), deref_chain[0].value.clone()),
    };
    if iterate_method_candidates_by_receiver(
@@ -524,9 +520,9 @@ fn iterate_inherent_methods(
        None => return false,
    };
    for krate in def_crates {
-        let impls = db.impls_in_crate(krate);
+        let impls = db.inherent_impls_in_crate(krate);
-        for impl_def in impls.lookup_impl_defs(&self_ty.value) {
+        for &impl_def in impls.for_self_ty(&self_ty.value) {
            for &item in db.impl_data(impl_def).items.iter() {
                if !is_valid_candidate(db, name, receiver_ty, item, self_ty) {
                    continue;
@@ -612,18 +608,19 @@ pub(crate) fn inherent_impl_substs(
    // we create a var for each type parameter of the impl; we need to keep in
    // mind here that `self_ty` might have vars of its own
    let vars = Substs::build_for_def(db, impl_id)
-        .fill_with_bound_vars(DebruijnIndex::INNERMOST, self_ty.num_vars)
+        .fill_with_bound_vars(DebruijnIndex::INNERMOST, self_ty.kinds.len())
        .build();
    let self_ty_with_vars = db.impl_self_ty(impl_id).subst(&vars);
-    let self_ty_with_vars =
+    let mut kinds = self_ty.kinds.to_vec();
-        Canonical { num_vars: vars.len() + self_ty.num_vars, value: self_ty_with_vars };
+    kinds.extend(iter::repeat(TyKind::General).take(vars.len()));
-    let substs = super::infer::unify(&self_ty_with_vars, self_ty);
+    let tys = Canonical { kinds: kinds.into(), value: (self_ty_with_vars, self_ty.value.clone()) };
+    let substs = super::infer::unify(&tys);
    // We only want the substs for the vars we added, not the ones from self_ty.
    // Also, if any of the vars we added are still in there, we replace them by
    // Unknown. I think this can only really happen if self_ty contained
    // Unknown, and in that case we want the result to contain Unknown in those
    // places again.
-    substs.map(|s| fallback_bound_vars(s.suffix(vars.len()), self_ty.num_vars))
+    substs.map(|s| fallback_bound_vars(s.suffix(vars.len()), self_ty.kinds.len()))
 }
 /// This replaces any 'free' Bound vars in `s` (i.e. those with indices past
@@ -683,15 +680,15 @@ fn generic_implements_goal(
    trait_: TraitId,
    self_ty: Canonical<Ty>,
 ) -> Canonical<InEnvironment<super::Obligation>> {
-    let num_vars = self_ty.num_vars;
+    let mut kinds = self_ty.kinds.to_vec();
    let substs = super::Substs::build_for_def(db, trait_)
        .push(self_ty.value)
-        .fill_with_bound_vars(DebruijnIndex::INNERMOST, num_vars)
+        .fill_with_bound_vars(DebruijnIndex::INNERMOST, kinds.len())
        .build();
-    let num_vars = substs.len() - 1 + self_ty.num_vars;
+    kinds.extend(iter::repeat(TyKind::General).take(substs.len() - 1));
    let trait_ref = TraitRef { trait_, substs };
    let obligation = super::Obligation::Trait(trait_ref);
-    Canonical { num_vars, value: InEnvironment::new(env, obligation) }
+    Canonical { kinds: kinds.into(), value: InEnvironment::new(env, obligation) }
 }
 fn autoderef_method_receiver(
@@ -704,9 +701,9 @@ fn autoderef_method_receiver(
    if let Some(Ty::Apply(ApplicationTy { ctor: TypeCtor::Array, parameters })) =
        deref_chain.last().map(|ty| &ty.value)
    {
-        let num_vars = deref_chain.last().unwrap().num_vars;
+        let kinds = deref_chain.last().unwrap().kinds.clone();
        let unsized_ty = Ty::apply(TypeCtor::Slice, parameters.clone());
-        deref_chain.push(Canonical { value: unsized_ty, num_vars })
+        deref_chain.push(Canonical { value: unsized_ty, kinds })
    }
    deref_chain
 }
diff --git a/crates/ra_hir_ty/src/test_db.rs b/crates/ra_hir_ty/src/test_db.rs
index 0481a7b12..fddf0604d 100644
--- a/crates/ra_hir_ty/src/test_db.rs
+++ b/crates/ra_hir_ty/src/test_db.rs
@@ -8,8 +8,10 @@ use std::{
 use hir_def::{db::DefDatabase, AssocItemId, ModuleDefId, ModuleId};
 use hir_expand::{db::AstDatabase, diagnostics::DiagnosticSink};
 use ra_db::{salsa, CrateId, FileId, FileLoader, FileLoaderDelegate, SourceDatabase, Upcast};
-use rustc_hash::FxHashSet;
+use ra_syntax::TextRange;
+use rustc_hash::{FxHashMap, FxHashSet};
 use stdx::format_to;
+use test_utils::extract_annotations;
 use crate::{
    db::HirDatabase, diagnostics::Diagnostic, expr::ExprValidator,
@@ -155,17 +157,27 @@ impl TestDB {
        (buf, count)
    }
-    pub fn all_files(&self) -> Vec<FileId> {
+    pub fn extract_annotations(&self) -> FxHashMap<FileId, Vec<(TextRange, String)>> {
-        let mut res = Vec::new();
+        let mut files = Vec::new();
        let crate_graph = self.crate_graph();
        for krate in crate_graph.iter() {
            let crate_def_map = self.crate_def_map(krate);
            for (module_id, _) in crate_def_map.modules.iter() {
                let file_id = crate_def_map[module_id].origin.file_id();
-                res.extend(file_id)
+                files.extend(file_id)
            }
        }
-        res
+        files
+            .into_iter()
+            .filter_map(|file_id| {
+                let text = self.file_text(file_id);
+                let annotations = extract_annotations(&text);
+                if annotations.is_empty() {
+                    return None;
+                }
+                Some((file_id, annotations))
+            })
+            .collect()
    }
 }
diff --git a/crates/ra_hir_ty/src/tests.rs b/crates/ra_hir_ty/src/tests.rs
index 5424e6bb1..eeac34d14 100644
--- a/crates/ra_hir_ty/src/tests.rs
+++ b/crates/ra_hir_ty/src/tests.rs
@@ -28,7 +28,6 @@ use ra_syntax::{
    SyntaxNode,
 };
 use stdx::format_to;
-use test_utils::extract_annotations;
 use crate::{
    db::HirDatabase, display::HirDisplay, infer::TypeMismatch, test_db::TestDB, InferenceResult, Ty,
@@ -49,9 +48,7 @@ fn check_types_source_code(ra_fixture: &str) {
 fn check_types_impl(ra_fixture: &str, display_source: bool) {
    let db = TestDB::with_files(ra_fixture);
    let mut checked_one = false;
-    for file_id in db.all_files() {
+    for (file_id, annotations) in db.extract_annotations() {
-        let text = db.parse(file_id).syntax_node().to_string();
-        let annotations = extract_annotations(&text);
        for (range, expected) in annotations {
            let ty = type_at_range(&db, FileRange { file_id, range });
            let actual = if display_source {
@@ -511,6 +508,30 @@ fn no_such_field_with_feature_flag_diagnostics_on_struct_fields() {
 }
 #[test]
+fn no_such_field_with_type_macro() {
+    let diagnostics = TestDB::with_files(
+        r"
+        macro_rules! Type {
+            () => { u32 };
+        }
+        struct Foo {
+            bar: Type![],
+        }
+        impl Foo {
+            fn new() -> Self {
+                Foo { bar: 0 }
+            }
+        }
+        ",
+    )
+    .diagnostics()
+    .0;
+    assert_snapshot!(diagnostics, @r###""###);
+}
+#[test]
 fn missing_record_pat_field_diagnostic() {
    let diagnostics = TestDB::with_files(
        r"
diff --git a/crates/ra_hir_ty/src/tests/traits.rs b/crates/ra_hir_ty/src/tests/traits.rs
index 01c919a7e..766790576 100644
--- a/crates/ra_hir_ty/src/tests/traits.rs
+++ b/crates/ra_hir_ty/src/tests/traits.rs
@@ -3029,3 +3029,21 @@ fn infer_dyn_fn_output() {
    "###
    );
 }
+#[test]
+fn variable_kinds() {
+    check_types(
+        r#"
+trait Trait<T> { fn get(self, t: T) -> T; }
+struct S;
+impl Trait<u128> for S {}
+impl Trait<f32> for S {}
+fn test() {
+    S.get(1);
+  //^^^^^^^^ u128
+    S.get(1.);
+  //^^^^^^^^ f32
+}
+        "#,
+    );
+}
diff --git a/crates/ra_hir_ty/src/traits.rs b/crates/ra_hir_ty/src/traits.rs
index 6f43c3a22..2a6d7faef 100644
--- a/crates/ra_hir_ty/src/traits.rs
+++ b/crates/ra_hir_ty/src/traits.rs
@@ -1,5 +1,5 @@
 //! Trait solving using Chalk.
-use std::{panic, sync::Arc};
+use std::sync::Arc;
 use chalk_ir::cast::Cast;
 use hir_def::{
@@ -8,7 +8,7 @@ use hir_def::{
 use ra_db::{impl_intern_key, salsa, CrateId};
 use ra_prof::profile;
-use crate::{db::HirDatabase, DebruijnIndex};
+use crate::{db::HirDatabase, DebruijnIndex, Substs};
 use super::{Canonical, GenericPredicate, HirDisplay, ProjectionTy, TraitRef, Ty, TypeWalk};
@@ -190,15 +190,7 @@ fn solution_from_chalk(
    solution: chalk_solve::Solution<Interner>,
 ) -> Solution {
    let convert_subst = |subst: chalk_ir::Canonical<chalk_ir::Substitution<Interner>>| {
-        let value = subst
+        let result = from_chalk(db, subst);
-            .value
-            .iter(&Interner)
-            .map(|p| match p.ty(&Interner) {
-                Some(ty) => from_chalk(db, ty.clone()),
-                None => unimplemented!(),
-            })
-            .collect();
-        let result = Canonical { value, num_vars: subst.binders.len(&Interner) };
        SolutionVariables(result)
    };
    match solution {
@@ -222,7 +214,7 @@ fn solution_from_chalk(
 }
 #[derive(Clone, Debug, PartialEq, Eq)]
-pub struct SolutionVariables(pub Canonical<Vec<Ty>>);
+pub struct SolutionVariables(pub Canonical<Substs>);
 #[derive(Clone, Debug, PartialEq, Eq)]
 /// A (possible) solution for a proposed goal.
diff --git a/crates/ra_hir_ty/src/traits/chalk.rs b/crates/ra_hir_ty/src/traits/chalk.rs
index 8ef4941c0..c97b81d57 100644
--- a/crates/ra_hir_ty/src/traits/chalk.rs
+++ b/crates/ra_hir_ty/src/traits/chalk.rs
@@ -77,8 +77,8 @@ impl<'a> chalk_solve::RustIrDatabase<Interner> for ChalkContext<'a> {
        // Note: Since we're using impls_for_trait, only impls where the trait
        // can be resolved should ever reach Chalk. `impl_datum` relies on that
        // and will panic if the trait can't be resolved.
-        let in_deps = self.db.impls_from_deps(self.krate);
+        let in_deps = self.db.trait_impls_in_deps(self.krate);
-        let in_self = self.db.impls_in_crate(self.krate);
+        let in_self = self.db.trait_impls_in_crate(self.krate);
        let impl_maps = [in_deps, in_self];
        let id_to_chalk = |id: hir_def::ImplId| Impl::ImplDef(id).to_chalk(self.db);
@@ -87,14 +87,12 @@ impl<'a> chalk_solve::RustIrDatabase<Interner> for ChalkContext<'a> {
            Some(fp) => impl_maps
                .iter()
                .flat_map(|crate_impl_defs| {
-                    crate_impl_defs.lookup_impl_defs_for_trait_and_ty(trait_, fp).map(id_to_chalk)
+                    crate_impl_defs.for_trait_and_self_ty(trait_, fp).map(id_to_chalk)
                })
                .collect(),
            None => impl_maps
                .iter()
-                .flat_map(|crate_impl_defs| {
+                .flat_map(|crate_impl_defs| crate_impl_defs.for_trait(trait_).map(id_to_chalk))
-                    crate_impl_defs.lookup_impl_defs_for_trait(trait_).map(id_to_chalk)
-                })
                .collect(),
        };
diff --git a/crates/ra_hir_ty/src/traits/chalk/mapping.rs b/crates/ra_hir_ty/src/traits/chalk/mapping.rs
index ac82ea831..433d6aa03 100644
--- a/crates/ra_hir_ty/src/traits/chalk/mapping.rs
+++ b/crates/ra_hir_ty/src/traits/chalk/mapping.rs
@@ -17,7 +17,7 @@ use crate::{
    primitive::{FloatBitness, FloatTy, IntBitness, IntTy, Signedness},
    traits::{builtin, AssocTyValue, Canonical, Impl, Obligation},
    ApplicationTy, CallableDef, GenericPredicate, InEnvironment, OpaqueTy, OpaqueTyId,
-    ProjectionPredicate, ProjectionTy, Substs, TraitEnvironment, TraitRef, Ty, TypeCtor,
+    ProjectionPredicate, ProjectionTy, Substs, TraitEnvironment, TraitRef, Ty, TyKind, TypeCtor,
 };
 use super::interner::*;
@@ -555,22 +555,39 @@ where