313 files changed, 13661 insertions, 11706 deletions

diff --git a/.github/workflows/release.yaml b/.github/workflows/release.yaml
index 2c1192f07..3f52f31f8 100644
--- a/.github/workflows/release.yaml
+++ b/.github/workflows/release.yaml
@@ -39,7 +39,6 @@ jobs:
       with:
         toolchain: stable
         profile: minimal
-        target: x86_64-unknown-linux-musl
         override: true
 
     - name: Install Nodejs
diff --git a/.vscode/launch.json b/.vscode/launch.json
index 3f74d7566..6a2fff906 100644
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@@ -41,7 +41,7 @@
       "outFiles": [
         "${workspaceFolder}/editors/code/out/**/*.js"
       ],
-      "preLaunchTask": "Build Extension",
+      "preLaunchTask": "Build Server and Extension",
       "skipFiles": [
         "<node_internals>/**/*.js"
       ],
@@ -62,7 +62,7 @@
       "outFiles": [
         "${workspaceFolder}/editors/code/out/**/*.js"
       ],
-      "preLaunchTask": "Build Extension",
+      "preLaunchTask": "Build Server (Release) and Extension",
       "skipFiles": [
         "<node_internals>/**/*.js"
       ],
diff --git a/.vscode/tasks.json b/.vscode/tasks.json
index 4037e7cce..0969ce89a 100644
--- a/.vscode/tasks.json
+++ b/.vscode/tasks.json
@@ -4,7 +4,7 @@
   "version": "2.0.0",
   "tasks": [
     {
-      "label": "Build Extension",
+      "label": "Build Extension in Background",
       "group": "build",
       "type": "npm",
       "script": "watch",
@@ -16,11 +16,40 @@
       "isBackground": true,
     },
     {
+      "label": "Build Extension",
+      "group": "build",
+      "type": "npm",
+      "script": "build",
+      "path": "editors/code/",
+      "problemMatcher": {
+        "base": "$tsc",
+        "fileLocation": ["relative", "${workspaceFolder}/editors/code/"]
+      },
+    },
+    {
       "label": "Build Server",
       "group": "build",
       "type": "shell",
       "command": "cargo build --package rust-analyzer",
       "problemMatcher": "$rustc"
     },
+    {
+      "label": "Build Server (Release)",
+      "group": "build",
+      "type": "shell",
+      "command": "cargo build --release --package rust-analyzer",
+      "problemMatcher": "$rustc"
+    },
+
+    {
+      "label": "Build Server and Extension",
+      "dependsOn": ["Build Server", "Build Extension"],
+      "problemMatcher": "$rustc"
+    },
+    {
+      "label": "Build Server (Release) and Extension",
+      "dependsOn": ["Build Server (Release)", "Build Extension"],
+      "problemMatcher": "$rustc"
+    }
   ]
 }
diff --git a/Cargo.lock b/Cargo.lock
index 367ff3f82..5d50a766f 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -58,9 +58,9 @@ dependencies = [
 
 [[package]]
 name = "backtrace-sys"
-version = "0.1.36"
+version = "0.1.37"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "78848718ee1255a2485d1309ad9cdecfc2e7d0362dd11c6829364c6b35ae1bc7"
+checksum = "18fbebbe1c9d1f383a9cc7e8ccdb471b91c8d024ee9c2ca5b5346121fe8b4399"
 dependencies = [
  "cc",
  "libc",
@@ -68,9 +68,9 @@ dependencies = [
 
 [[package]]
 name = "base64"
-version = "0.11.0"
+version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b41b7ea54a0c9d92199de89e20e58d49f02f8e699814ef3fdf266f6f748d15c7"
+checksum = "7d5ca2cd0adc3f48f9e9ea5a6bbdf9ccc0bfade884847e484d452414c7ccffb3"
 
 [[package]]
 name = "bitflags"
@@ -170,7 +170,7 @@ dependencies = [
  "chalk-ir",
  "chalk-macros",
  "chalk-rust-ir",
- "ena",
+ "ena 0.13.1",
  "itertools",
  "petgraph",
  "rustc-hash",
@@ -199,14 +199,15 @@ dependencies = [
 
 [[package]]
 name = "console"
-version = "0.10.0"
+version = "0.10.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6728a28023f207181b193262711102bfbaf47cc9d13bc71d0736607ef8efe88c"
+checksum = "2586208b33573b7f76ccfbe5adb076394c88deaf81b84d7213969805b0a952a7"
 dependencies = [
  "clicolors-control",
  "encode_unicode",
  "lazy_static",
  "libc",
+ "terminal_size",
  "termios",
  "winapi 0.3.8",
 ]
@@ -316,6 +317,15 @@ dependencies = [
 ]
 
 [[package]]
+name = "ena"
+version = "0.14.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d7402b94a93c24e742487327a7cd839dc9d36fec9de9fb25b09f2dae459f36c3"
+dependencies = [
+ "log",
+]
+
+[[package]]
 name = "encode_unicode"
 version = "0.3.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -381,9 +391,9 @@ dependencies = [
 
 [[package]]
 name = "fst"
-version = "0.4.1"
+version = "0.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4eaf9ea41cc964d742f7fc7861db75d2d6e83a3ce0d897d5c6f8b621f015ddc8"
+checksum = "81f9cac32c1741cdf6b66be7dcf0d9c7f25ccf12f8aa84c16cfa31f9f14513b3"
 
 [[package]]
 name = "fuchsia-zircon"
@@ -447,9 +457,9 @@ dependencies = [
 
 [[package]]
 name = "hermit-abi"
-version = "0.1.11"
+version = "0.1.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8a0d737e0f947a1864e93d33fdef4af8445a00d1ed8dc0c8ddb73139ea6abf15"
+checksum = "61565ff7aaace3525556587bd2dc31d4a07071957be715e63ce7b1eccf51a8f4"
 dependencies = [
  "libc",
 ]
@@ -645,9 +655,9 @@ dependencies = [
 
 [[package]]
 name = "lsp-types"
-version = "0.73.0"
+version = "0.74.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "93d0cf64ea141b43d9e055f6b9df13f0bce32b103d84237509ce0a571ab9b159"
+checksum = "57c0e6a2b8837d27b29deb3f3e6dc1c6d2f57947677f9be1024e482ec5b59525"
 dependencies = [
  "base64",
  "bitflags",
@@ -696,9 +706,9 @@ dependencies = [
 
 [[package]]
 name = "mio"
-version = "0.6.21"
+version = "0.6.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "302dec22bcf6bae6dfb69c647187f4b4d0fb6f535521f7bc022430ce8e12008f"
+checksum = "fce347092656428bc8eaf6201042cb551b8d67855af7374542a92a0fbfcac430"
 dependencies = [
  "cfg-if",
  "fuchsia-zircon",
@@ -739,9 +749,9 @@ dependencies = [
 
 [[package]]
 name = "net2"
-version = "0.2.33"
+version = "0.2.34"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "42550d9fb7b6684a6d404d9fa7250c2eb2646df731d1c06afc06dcee9e1bcf88"
+checksum = "2ba7c918ac76704fb42afcbbb43891e72731f3dcca3bef2a19786297baf14af7"
 dependencies = [
  "cfg-if",
  "libc",
@@ -814,9 +824,9 @@ dependencies = [
 
 [[package]]
 name = "paste"
-version = "0.1.10"
+version = "0.1.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ab4fb1930692d1b6a9cfabdde3d06ea0a7d186518e2f4d67660d8970e2fa647a"
+checksum = "a3c897744f63f34f7ae3a024d9162bb5001f4ad661dd24bea0dc9f075d2de1c6"
 dependencies = [
  "paste-impl",
  "proc-macro-hack",
@@ -824,9 +834,9 @@ dependencies = [
 
 [[package]]
 name = "paste-impl"
-version = "0.1.10"
+version = "0.1.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a62486e111e571b1e93b710b61e8f493c0013be39629b714cb166bdb06aa5a8a"
+checksum = "66fd6f92e3594f2dd7b3fc23e42d82e292f7bcda6d8e5dcd167072327234ab89"
 dependencies = [
  "proc-macro-hack",
  "proc-macro2",
@@ -885,9 +895,9 @@ dependencies = [
 
 [[package]]
 name = "quote"
-version = "1.0.3"
+version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2bdc6c187c65bca4260c9011c9e3132efe4909da44726bad24cf7572ae338d7f"
+checksum = "4c1f4b0efa5fc5e8ceb705136bfee52cfdb6a4e3509f770b478cd6ed434232a7"
 dependencies = [
  "proc-macro2",
 ]
@@ -1023,7 +1033,7 @@ dependencies = [
  "chalk-ir",
  "chalk-rust-ir",
  "chalk-solve",
- "ena",
+ "ena 0.14.0",
  "insta",
  "itertools",
  "log",
@@ -1193,9 +1203,9 @@ dependencies = [
 
 [[package]]
 name = "ra_vfs"
-version = "0.5.3"
+version = "0.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "58a265769d5e5655345a9fcbd870a1a7c3658558c0d8efaed79e0669358f46b8"
+checksum = "fcaa5615f420134aea7667253db101d03a5c5f300eac607872dc2a36407b2ac9"
 dependencies = [
  "crossbeam-channel",
  "jod-thread",
@@ -1374,9 +1384,9 @@ dependencies = [
 
 [[package]]
 name = "rustc-ap-rustc_lexer"
-version = "652.0.0"
+version = "656.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3a6a43c4d0889218c5e2ae68ffea239f303fc05ab1078c73f74e63feb87f7889"
+checksum = "9cbba98ec46e96a4663197dfa8c0378752de2006e314e5400c0ca74929d6692f"
 dependencies = [
  "unicode-xid",
 ]
@@ -1486,18 +1496,18 @@ checksum = "388a1df253eca08550bef6c72392cfe7c30914bf41df5269b68cbd6ff8f570a3"
 
 [[package]]
 name = "serde"
-version = "1.0.104"
+version = "1.0.106"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "414115f25f818d7dfccec8ee535d76949ae78584fc4f79a6f45a904bf8ab4449"
+checksum = "36df6ac6412072f67cf767ebbde4133a5b2e88e76dc6187fa7104cd16f783399"
 dependencies = [
  "serde_derive",
 ]
 
 [[package]]
 name = "serde_derive"
-version = "1.0.104"
+version = "1.0.106"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "128f9e303a5a29922045a830221b8f78ec74a5f544944f3d5984f8ec3895ef64"
+checksum = "9e549e3abf4fb8621bd1609f11dfc9f5e50320802273b12f3811a67e6716ea6c"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -1506,9 +1516,9 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.51"
+version = "1.0.52"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "da07b57ee2623368351e9a0488bb0b261322a15a6e0ae53e243cbdc0f4208da9"
+checksum = "a7894c8ed05b7a3a279aeb79025fdec1d3158080b75b98a08faf2806bb799edd"
 dependencies = [
  "itoa",
  "ryu",
@@ -1607,6 +1617,16 @@ dependencies = [
 ]
 
 [[package]]
+name = "terminal_size"
+version = "0.1.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8038f95fc7a6f351163f4b964af631bd26c9e828f7db085f2a84aca56f70d13b"
+dependencies = [
+ "libc",
+ "winapi 0.3.8",
+]
+
+[[package]]
 name = "termios"
 version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/crates/ra_assists/src/ast_transform.rs b/crates/ra_assists/src/ast_transform.rs
index 52b4c82db..9ac65ab39 100644
--- a/crates/ra_assists/src/ast_transform.rs
+++ b/crates/ra_assists/src/ast_transform.rs
@@ -85,6 +85,7 @@ impl<'a> SubstituteTypeParams<'a> {
             ast::TypeRef::PathType(path_type) => path_type.path()?,
             _ => return None,
         };
+        // FIXME: use `hir::Path::from_src` instead.
         let path = hir::Path::from_ast(path)?;
         let resolution = self.source_scope.resolve_hir_path(&path)?;
         match resolution {
@@ -128,6 +129,7 @@ impl<'a> QualifyPaths<'a> {
             // don't try to qualify `Fn(Foo) -> Bar` paths, they are in prelude anyway
             return None;
         }
+        // FIXME: use `hir::Path::from_src` instead.
         let hir_path = hir::Path::from_ast(p.clone());
         let resolution = self.source_scope.resolve_hir_path(&hir_path?)?;
         match resolution {
diff --git a/crates/ra_assists/src/doc_tests/generated.rs b/crates/ra_assists/src/doc_tests/generated.rs
index e4fa9ee36..6696cc832 100644
--- a/crates/ra_assists/src/doc_tests/generated.rs
+++ b/crates/ra_assists/src/doc_tests/generated.rs
@@ -180,7 +180,9 @@ trait Trait<T> {
 }
 
 impl Trait<u32> for () {
-    fn foo(&self) -> u32 { todo!() }
+    fn foo(&self) -> u32 {
+        todo!()
+    }
 
 }
 "#####,
@@ -726,3 +728,22 @@ use std::{collections::HashMap};
 "#####,
     )
 }
+
+#[test]
+fn doctest_unwrap_block() {
+    check(
+        "unwrap_block",
+        r#####"
+fn foo() {
+    if true {<|>
+        println!("foo");
+    }
+}
+"#####,
+        r#####"
+fn foo() {
+    println!("foo");
+}
+"#####,
+    )
+}
diff --git a/crates/ra_assists/src/handlers/add_from_impl_for_enum.rs b/crates/ra_assists/src/handlers/add_from_impl_for_enum.rs
index 03806724a..49deb6701 100644
--- a/crates/ra_assists/src/handlers/add_from_impl_for_enum.rs
+++ b/crates/ra_assists/src/handlers/add_from_impl_for_enum.rs
@@ -1,11 +1,12 @@
+use ra_ide_db::RootDatabase;
 use ra_syntax::{
     ast::{self, AstNode, NameOwner},
     TextSize,
 };
 use stdx::format_to;
 
-use crate::{Assist, AssistCtx, AssistId};
-use ra_ide_db::RootDatabase;
+use crate::{utils::FamousDefs, Assist, AssistCtx, AssistId};
+use test_utils::tested_by;
 
 // Assist add_from_impl_for_enum
 //
@@ -41,7 +42,8 @@ pub(crate) fn add_from_impl_for_enum(ctx: AssistCtx) -> Option<Assist> {
         _ => return None,
     };
 
-    if already_has_from_impl(ctx.sema, &variant) {
+    if existing_from_impl(ctx.sema, &variant).is_some() {
+        tested_by!(test_add_from_impl_already_exists);
         return None;
     }
 
@@ -70,41 +72,33 @@ impl From<{0}> for {1} {{
     )
 }
 
-fn already_has_from_impl(
+fn existing_from_impl(
     sema: &'_ hir::Semantics<'_, RootDatabase>,
     variant: &ast::EnumVariant,
-) -> bool {
-    let scope = sema.scope(&variant.syntax());
+) -> Option<()> {
+    let variant = sema.to_def(variant)?;
+    let enum_ = variant.parent_enum(sema.db);
+    let krate = enum_.module(sema.db).krate();
 
-    let from_path = ast::make::path_from_text("From");
-    let from_hir_path = match hir::Path::from_ast(from_path) {
-        Some(p) => p,
-        None => return false,
-    };
-    let from_trait = match scope.resolve_hir_path(&from_hir_path) {
-        Some(hir::PathResolution::Def(hir::ModuleDef::Trait(t))) => t,
-        _ => return false,
-    };
+    let from_trait = FamousDefs(sema, krate).core_convert_From()?;
 
-    let e: hir::Enum = match sema.to_def(&variant.parent_enum()) {
-        Some(e) => e,
-        None => return false,
-    };
-    let e_ty = e.ty(sema.db);
+    let enum_type = enum_.ty(sema.db);
 
-    let hir_enum_var: hir::EnumVariant = match sema.to_def(variant) {
-        Some(ev) => ev,
-        None => return false,
-    };
-    let var_ty = hir_enum_var.fields(sema.db)[0].signature_ty(sema.db);
+    let wrapped_type = variant.fields(sema.db).get(0)?.signature_ty(sema.db);
 
-    e_ty.impls_trait(sema.db, from_trait, &[var_ty])
+    if enum_type.impls_trait(sema.db, from_trait, &[wrapped_type]) {
+        Some(())
+    } else {
+        None
+    }
 }
 
 #[cfg(test)]
 mod tests {
     use super::*;
+
     use crate::helpers::{check_assist, check_assist_not_applicable};
+    use test_utils::covers;
 
     #[test]
     fn test_add_from_impl_for_enum() {
@@ -136,36 +130,40 @@ mod tests {
         );
     }
 
+    fn check_not_applicable(ra_fixture: &str) {
+        let fixture =
+            format!("//- main.rs crate:main deps:core\n{}\n{}", ra_fixture, FamousDefs::FIXTURE);
+        check_assist_not_applicable(add_from_impl_for_enum, &fixture)
+    }
+
     #[test]
     fn test_add_from_impl_no_element() {
-        check_assist_not_applicable(add_from_impl_for_enum, "enum A { <|>One }");
+        check_not_applicable("enum A { <|>One }");
     }
 
     #[test]
     fn test_add_from_impl_more_than_one_element_in_tuple() {
-        check_assist_not_applicable(add_from_impl_for_enum, "enum A { <|>One(u32, String) }");
+        check_not_applicable("enum A { <|>One(u32, String) }");
     }
 
     #[test]
     fn test_add_from_impl_struct_variant() {
-        check_assist_not_applicable(add_from_impl_for_enum, "enum A { <|>One { x: u32 } }");
+        check_not_applicable("enum A { <|>One { x: u32 } }");
     }
 
     #[test]
     fn test_add_from_impl_already_exists() {
-        check_assist_not_applicable(
-            add_from_impl_for_enum,
-            r#"enum A { <|>One(u32), }
+        covers!(test_add_from_impl_already_exists);
+        check_not_applicable(
+            r#"
+enum A { <|>One(u32), }
 
 impl From<u32> for A {
     fn from(v: u32) -> Self {
         A::One(v)
     }
 }
-
-pub trait From<T> {
-    fn from(T) -> Self;
-}"#,
+"#,
         );
     }
 
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 2d6d44980..e466c9a86 100644
--- a/crates/ra_assists/src/handlers/add_missing_impl_members.rs
+++ b/crates/ra_assists/src/handlers/add_missing_impl_members.rs
@@ -1,6 +1,10 @@
 use hir::HasSource;
 use ra_syntax::{
-    ast::{self, edit, make, AstNode, NameOwner},
+    ast::{
+        self,
+        edit::{self, IndentLevel},
+        make, AstNode, NameOwner,
+    },
     SmolStr,
 };
 
@@ -40,7 +44,9 @@ enum AddMissingImplMembersMode {
 // }
 //
 // impl Trait<u32> for () {
-//     fn foo(&self) -> u32 { todo!() }
+//     fn foo(&self) -> u32 {
+//         todo!()
+//     }
 //
 // }
 // ```
@@ -165,7 +171,9 @@ fn add_missing_impl_members_inner(
 
 fn add_body(fn_def: ast::FnDef) -> ast::FnDef {
     if fn_def.body().is_none() {
-        fn_def.with_body(make::block_from_expr(make::expr_todo()))
+        let body = make::block_expr(None, Some(make::expr_todo()));
+        let body = IndentLevel(1).increase_indent(body);
+        fn_def.with_body(body)
     } else {
         fn_def
     }
@@ -181,7 +189,7 @@ mod tests {
     fn test_add_missing_impl_members() {
         check_assist(
             add_missing_impl_members,
-            "
+            r#"
 trait Foo {
     type Output;
 
@@ -197,8 +205,8 @@ struct S;
 impl Foo for S {
     fn bar(&self) {}
 <|>
-}",
-            "
+}"#,
+            r#"
 trait Foo {
     type Output;
 
@@ -215,10 +223,14 @@ impl Foo for S {
     fn bar(&self) {}
     <|>type Output;
     const CONST: usize = 42;
-    fn foo(&self) { todo!() }
-    fn baz(&self) { todo!() }
+    fn foo(&self) {
+        todo!()
+    }
+    fn baz(&self) {
+        todo!()
+    }
 
-}",
+}"#,
         );
     }
 
@@ -226,7 +238,7 @@ impl Foo for S {
     fn test_copied_overriden_members() {
         check_assist(
             add_missing_impl_members,
-            "
+            r#"
 trait Foo {
     fn foo(&self);
     fn bar(&self) -> bool { true }
@@ -238,8 +250,8 @@ struct S;
 impl Foo for S {
     fn bar(&self) {}
 <|>
-}",
-            "
+}"#,
+            r#"
 trait Foo {
     fn foo(&self);
     fn bar(&self) -> bool { true }
@@ -250,9 +262,11 @@ struct S;
 
 impl Foo for S {
     fn bar(&self) {}
-    <|>fn foo(&self) { todo!() }
+    <|>fn foo(&self) {
+        todo!()
+    }
 
-}",
+}"#,
         );
     }
 
@@ -260,16 +274,18 @@ impl Foo for S {
     fn test_empty_impl_def() {
         check_assist(
             add_missing_impl_members,
-            "
+            r#"
 trait Foo { fn foo(&self); }
 struct S;
-impl Foo for S { <|> }",
-            "
+impl Foo for S { <|> }"#,
+            r#"
 trait Foo { fn foo(&self); }
 struct S;
 impl Foo for S {
-    <|>fn foo(&self) { todo!() }
-}",
+    <|>fn foo(&self) {
+        todo!()
+    }
+}"#,
         );
     }
 
@@ -277,16 +293,18 @@ impl Foo for S {
     fn fill_in_type_params_1() {
         check_assist(
             add_missing_impl_members,
-            "
+            r#"
 trait Foo<T> { fn foo(&self, t: T) -> &T; }
 struct S;
-impl Foo<u32> for S { <|> }",
-            "
+impl Foo<u32> for S { <|> }"#,
+            r#"
 trait Foo<T> { fn foo(&self, t: T) -> &T; }
 struct S;
 impl Foo<u32> for S {
-    <|>fn foo(&self, t: u32) -> &u32 { todo!() }
-}",
+    <|>fn foo(&self, t: u32) -> &u32 {
+        todo!()
+    }
+}"#,
         );
     }
 
@@ -294,16 +312,18 @@ impl Foo<u32> for S {
     fn fill_in_type_params_2() {
         check_assist(
             add_missing_impl_members,
-            "
+            r#"
 trait Foo<T> { fn foo(&self, t: T) -> &T; }
 struct S;
-impl<U> Foo<U> for S { <|> }",
-            "
+impl<U> Foo<U> for S { <|> }"#,
+            r#"
 trait Foo<T> { fn foo(&self, t: T) -> &T; }
 struct S;
 impl<U> Foo<U> for S {
-    <|>fn foo(&self, t: U) -> &U { todo!() }
-}",
+    <|>fn foo(&self, t: U) -> &U {
+        todo!()
+    }
+}"#,
         );
     }
 
@@ -311,16 +331,18 @@ impl<U> Foo<U> for S {
     fn test_cursor_after_empty_impl_def() {
         check_assist(
             add_missing_impl_members,
-            "
+            r#"
 trait Foo { fn foo(&self); }
 struct S;
-impl Foo for S {}<|>",
-            "
+impl Foo for S {}<|>"#,
+            r#"
 trait Foo { fn foo(&self); }
 struct S;
 impl Foo for S {
-    <|>fn foo(&self) { todo!() }
-}",
+    <|>fn foo(&self) {
+        todo!()
+    }
+}"#,
         )
     }
 
@@ -328,22 +350,24 @@ impl Foo for S {
     fn test_qualify_path_1() {
         check_assist(
             add_missing_impl_members,
-            "
+            r#"
 mod foo {
     pub struct Bar;
     trait Foo { fn foo(&self, bar: Bar); }
 }
 struct S;
-impl foo::Foo for S { <|> }",
-            "
+impl foo::Foo for S { <|> }"#,
+            r#"
 mod foo {
     pub struct Bar;
     trait Foo { fn foo(&self, bar: Bar); }
 }
 struct S;
 impl foo::Foo for S {
-    <|>fn foo(&self, bar: foo::Bar) { todo!() }
-}",
+    <|>fn foo(&self, bar: foo::Bar) {
+        todo!()
+    }
+}"#,
         );
     }
 
@@ -351,22 +375,24 @@ impl foo::Foo for S {
     fn test_qualify_path_generic() {
         check_assist(
             add_missing_impl_members,
-            "
+            r#"
 mod foo {
     pub struct Bar<T>;
     trait Foo { fn foo(&self, bar: Bar<u32>); }
 }
 struct S;
-impl foo::Foo for S { <|> }",
-            "
+impl foo::Foo for S { <|> }"#,
+            r#"
 mod foo {
     pub struct Bar<T>;
     trait Foo { fn foo(&self, bar: Bar<u32>); }
 }
 struct S;
 impl foo::Foo for S {
-    <|>fn foo(&self, bar: foo::Bar<u32>) { todo!() }
-}",
+    <|>fn foo(&self, bar: foo::Bar<u32>) {
+        todo!()
+    }
+}"#,
         );
     }
 
@@ -374,22 +400,24 @@ impl foo::Foo for S {
     fn test_qualify_path_and_substitute_param() {
         check_assist(
             add_missing_impl_members,
-            "
+            r#"
 mod foo {
     pub struct Bar<T>;
     trait Foo<T> { fn foo(&self, bar: Bar<T>); }
 }
 struct S;
-impl foo::Foo<u32> for S { <|> }",
-            "
+impl foo::Foo<u32> for S { <|> }"#,
+            r#"
 mod foo {
     pub struct Bar<T>;
     trait Foo<T> { fn foo(&self, bar: Bar<T>); }
 }
 struct S;
 impl foo::Foo<u32> for S {
-    <|>fn foo(&self, bar: foo::Bar<u32>) { todo!() }
-}",
+    <|>fn foo(&self, bar: foo::Bar<u32>) {
+        todo!()
+    }
+}"#,
         );
     }
 
@@ -398,15 +426,15 @@ impl foo::Foo<u32> for S {
         // when substituting params, the substituted param should not be qualified!
         check_assist(
             add_missing_impl_members,
-            "
+            r#"
 mod foo {
     trait Foo<T> { fn foo(&self, bar: T); }
     pub struct Param;
 }
 struct Param;
 struct S;
-impl foo::Foo<Param> for S { <|> }",
-            "
+impl foo::Foo<Param> for S { <|> }"#,
+            r#"
 mod foo {
     trait Foo<T> { fn foo(&self, bar: T); }
     pub struct Param;
@@ -414,8 +442,10 @@ mod foo {
 struct Param;
 struct S;
 impl foo::Foo<Param> for S {
-    <|>fn foo(&self, bar: Param) { todo!() }
-}",
+    <|>fn foo(&self, bar: Param) {
+        todo!()
+    }
+}"#,
         );
     }
 
@@ -423,15 +453,15 @@ impl foo::Foo<Param> for S {
     fn test_qualify_path_associated_item() {
         check_assist(
             add_missing_impl_members,
-            "
+            r#"
 mod foo {
     pub struct Bar<T>;
     impl Bar<T> { type Assoc = u32; }
     trait Foo { fn foo(&self, bar: Bar<u32>::Assoc); }
 }
 struct S;
-impl foo::Foo for S { <|> }",
-            "
+impl foo::Foo for S { <|> }"#,
+            r#"
 mod foo {
     pub struct Bar<T>;
     impl Bar<T> { type Assoc = u32; }
@@ -439,8 +469,10 @@ mod foo {
 }
 struct S;
 impl foo::Foo for S {
-    <|>fn foo(&self, bar: foo::Bar<u32>::Assoc) { todo!() }
-}",
+    <|>fn foo(&self, bar: foo::Bar<u32>::Assoc) {
+        todo!()
+    }
+}"#,
         );
     }
 
@@ -448,15 +480,15 @@ impl foo::Foo for S {
     fn test_qualify_path_nested() {
         check_assist(
             add_missing_impl_members,
-            "
+            r#"
 mod foo {
     pub struct Bar<T>;
     pub struct Baz;
     trait Foo { fn foo(&self, bar: Bar<Baz>); }
 }
 struct S;
-impl foo::Foo for S { <|> }",
-            "
+impl foo::Foo for S { <|> }"#,
+            r#"
 mod foo {
     pub struct Bar<T>;
     pub struct Baz;
@@ -464,8 +496,10 @@ mod foo {
 }
 struct S;
 impl foo::Foo for S {
-    <|>fn foo(&self, bar: foo::Bar<foo::Baz>) { todo!() }
-}",
+    <|>fn foo(&self, bar: foo::Bar<foo::Baz>) {
+        todo!()
+    }
+}"#,
         );
     }
 
@@ -473,22 +507,24 @@ impl foo::Foo for S {
     fn test_qualify_path_fn_trait_notation() {
         check_assist(
             add_missing_impl_members,
-            "
+            r#"
 mod foo {
     pub trait Fn<Args> { type Output; }
     trait Foo { fn foo(&self, bar: dyn Fn(u32) -> i32); }
 }
 struct S;
-impl foo::Foo for S { <|> }",
-            "
+impl foo::Foo for S { <|> }"#,
+            r#"
 mod foo {
     pub trait Fn<Args> { type Output; }
     trait Foo { fn foo(&self, bar: dyn Fn(u32) -> i32); }
 }
 struct S;
 impl foo::Foo for S {
-    <|>fn foo(&self, bar: dyn Fn(u32) -> i32) { todo!() }
-}",
+    <|>fn foo(&self, bar: dyn Fn(u32) -> i32) {
+        todo!()
+    }
+}"#,
         );
     }
 
@@ -496,10 +532,10 @@ impl foo::Foo for S {
     fn test_empty_trait() {
         check_assist_not_applicable(
             add_missing_impl_members,
-            "
+            r#"
 trait Foo;
 struct S;
-impl Foo for S { <|> }",
+impl Foo for S { <|> }"#,
         )
     }
 
@@ -507,13 +543,13 @@ impl Foo for S { <|> }",
     fn test_ignore_unnamed_trait_members_and_default_methods() {
         check_assist_not_applicable(
             add_missing_impl_members,
-            "
+            r#"
 trait Foo {
     fn (arg: u32);
     fn valid(some: u32) -> bool { false }
 }
 struct S;
-impl Foo for S { <|> }",
+impl Foo for S { <|> }"#,
         )
     }
 
@@ -544,7 +580,9 @@ trait Foo {
 struct S;
 impl Foo for S {
     <|>type Output;
-    fn foo(&self) { todo!() }
+    fn foo(&self) {
+        todo!()
+    }
 }"#,
         )
     }
@@ -553,7 +591,7 @@ impl Foo for S {
     fn test_default_methods() {
         check_assist(
             add_missing_default_members,
-            "
+            r#"
 trait Foo {
     type Output;
 
@@ -563,8 +601,8 @@ trait Foo {
     fn foo(some: u32) -> bool;
 }
 struct S;
-impl Foo for S { <|> }",
-            "
+impl Foo for S { <|> }"#,
+            r#"
 trait Foo {
     type Output;
 
@@ -576,7 +614,7 @@ trait Foo {
 struct S;
 impl Foo for S {
     <|>fn valid(some: u32) -> bool { false }
-}",
+}"#,
         )
     }
 }
diff --git a/crates/ra_assists/src/handlers/early_return.rs b/crates/ra_assists/src/handlers/early_return.rs
index ea6c56f8c..eede2fe91 100644
--- a/crates/ra_assists/src/handlers/early_return.rs
+++ b/crates/ra_assists/src/handlers/early_return.rs
@@ -2,7 +2,7 @@ use std::{iter::once, ops::RangeInclusive};
 
 use ra_syntax::{
     algo::replace_children,
-    ast::{self, edit::IndentLevel, make, Block, Pat::TupleStructPat},
+    ast::{self, edit::IndentLevel, make},
     AstNode,
     SyntaxKind::{FN_DEF, LOOP_EXPR, L_CURLY, R_CURLY, WHILE_EXPR, WHITESPACE},
     SyntaxNode,
@@ -47,7 +47,7 @@ pub(crate) fn convert_to_guarded_return(ctx: AssistCtx) -> Option<Assist> {
     // Check if there is an IfLet that we can handle.
     let if_let_pat = match cond.pat() {
         None => None, // No IfLet, supported.
-        Some(TupleStructPat(pat)) if pat.args().count() == 1 => {
+        Some(ast::Pat::TupleStructPat(pat)) if pat.args().count() == 1 => {
             let path = pat.path()?;
             match path.qualifier() {
                 None => {
@@ -61,9 +61,9 @@ pub(crate) fn convert_to_guarded_return(ctx: AssistCtx) -> Option<Assist> {
     };
 
     let cond_expr = cond.expr()?;
-    let then_block = if_expr.then_branch()?.block()?;
+    let then_block = if_expr.then_branch()?;
 
-    let parent_block = if_expr.syntax().parent()?.ancestors().find_map(ast::Block::cast)?;
+    let parent_block = if_expr.syntax().parent()?.ancestors().find_map(ast::BlockExpr::cast)?;
 
     if parent_block.expr()? != if_expr.clone().into() {
         return None;
@@ -80,7 +80,7 @@ pub(crate) fn convert_to_guarded_return(ctx: AssistCtx) -> Option<Assist> {
         return None;
     }
 
-    let parent_container = parent_block.syntax().parent()?.parent()?;
+    let parent_container = parent_block.syntax().parent()?;
 
     let early_expression: ast::Expr = match parent_container.kind() {
         WHILE_EXPR | LOOP_EXPR => make::expr_continue(),
@@ -144,13 +144,13 @@ pub(crate) fn convert_to_guarded_return(ctx: AssistCtx) -> Option<Assist> {
             }
         };
         edit.target(if_expr.syntax().text_range());
-        edit.replace_ast(parent_block, ast::Block::cast(new_block).unwrap());
+        edit.replace_ast(parent_block, ast::BlockExpr::cast(new_block).unwrap());
         edit.set_cursor(cursor_position);
 
         fn replace(
             new_expr: &SyntaxNode,
-            then_block: &Block,
-            parent_block: &Block,
+            then_block: &ast::BlockExpr,
+            parent_block: &ast::BlockExpr,
             if_expr: &ast::IfExpr,
         ) -> SyntaxNode {
             let then_block_items = IndentLevel::from(1).decrease_indent(then_block.clone());
diff --git a/crates/ra_assists/src/handlers/inline_local_variable.rs b/crates/ra_assists/src/handlers/inline_local_variable.rs
index f5702f6e0..60ec536a7 100644
--- a/crates/ra_assists/src/handlers/inline_local_variable.rs
+++ b/crates/ra_assists/src/handlers/inline_local_variable.rs
@@ -89,6 +89,7 @@ pub(crate) fn inline_local_variable(ctx: AssistCtx) -> Option<Assist> {
             | (ast::Expr::ParenExpr(_), _)
             | (ast::Expr::PathExpr(_), _)
             | (ast::Expr::BlockExpr(_), _)
+            | (ast::Expr::EffectExpr(_), _)
             | (_, ast::Expr::CallExpr(_))
             | (_, ast::Expr::TupleExpr(_))
             | (_, ast::Expr::ArrayExpr(_))
diff --git a/crates/ra_assists/src/handlers/introduce_variable.rs b/crates/ra_assists/src/handlers/introduce_variable.rs
index eda9ac296..39c656305 100644
--- a/crates/ra_assists/src/handlers/introduce_variable.rs
+++ b/crates/ra_assists/src/handlers/introduce_variable.rs
@@ -111,7 +111,7 @@ fn valid_target_expr(node: SyntaxNode) -> Option<ast::Expr> {
 /// expression like a lambda or match arm.
 fn anchor_stmt(expr: ast::Expr) -> Option<(SyntaxNode, bool)> {
     expr.syntax().ancestors().find_map(|node| {
-        if let Some(expr) = node.parent().and_then(ast::Block::cast).and_then(|it| it.expr()) {
+        if let Some(expr) = node.parent().and_then(ast::BlockExpr::cast).and_then(|it| it.expr()) {
             if expr.syntax() == &node {
                 tested_by!(test_introduce_var_last_expr);
                 return Some((node, false));
diff --git a/crates/ra_assists/src/handlers/move_guard.rs b/crates/ra_assists/src/handlers/move_guard.rs
index d5ccdd91c..b084dd9ee 100644
--- a/crates/ra_assists/src/handlers/move_guard.rs
+++ b/crates/ra_assists/src/handlers/move_guard.rs
@@ -113,9 +113,9 @@ pub(crate) fn move_arm_cond_to_match_guard(ctx: AssistCtx) -> Option<Assist> {
         "Move condition to match guard",
         |edit| {
             edit.target(if_expr.syntax().text_range());
-            let then_only_expr = then_block.block().and_then(|it| it.statements().next()).is_none();
+            let then_only_expr = then_block.statements().next().is_none();
 
-            match &then_block.block().and_then(|it| it.expr()) {
+            match &then_block.expr() {
                 Some(then_expr) if then_only_expr => {
                     edit.replace(if_expr.syntax().text_range(), then_expr.syntax().text())
                 }
diff --git a/crates/ra_assists/src/handlers/replace_if_let_with_match.rs b/crates/ra_assists/src/handlers/replace_if_let_with_match.rs
index 0a0a88f3d..9841f6980 100644
--- a/crates/ra_assists/src/handlers/replace_if_let_with_match.rs
+++ b/crates/ra_assists/src/handlers/replace_if_let_with_match.rs
@@ -1,11 +1,10 @@
 use ra_fmt::unwrap_trivial_block;
 use ra_syntax::{
-    ast::{self, make},
+    ast::{self, edit::IndentLevel, make},
     AstNode,
 };
 
-use crate::{Assist, AssistCtx, AssistId};
-use ast::edit::IndentLevel;
+use crate::{utils::TryEnum, Assist, AssistCtx, AssistId};
 
 // Assist: replace_if_let_with_match
 //
@@ -44,15 +43,21 @@ pub(crate) fn replace_if_let_with_match(ctx: AssistCtx) -> Option<Assist> {
         ast::ElseBranch::IfExpr(_) => return None,
     };
 
-    ctx.add_assist(AssistId("replace_if_let_with_match"), "Replace with match", |edit| {
+    let sema = ctx.sema;
+    ctx.add_assist(AssistId("replace_if_let_with_match"), "Replace with match", move |edit| {
         let match_expr = {
             let then_arm = {
                 let then_expr = unwrap_trivial_block(then_block);
-                make::match_arm(vec![pat], then_expr)
+                make::match_arm(vec![pat.clone()], then_expr)
             };
             let else_arm = {
+                let pattern = sema
+                    .type_of_pat(&pat)
+                    .and_then(|ty| TryEnum::from_ty(sema, &ty))
+                    .map(|it| it.sad_pattern())
+                    .unwrap_or_else(|| make::placeholder_pat().into());
                 let else_expr = unwrap_trivial_block(else_block);
-                make::match_arm(vec![make::placeholder_pat().into()], else_expr)
+                make::match_arm(vec![pattern], else_expr)
             };
             make::expr_match(expr, make::match_arm_list(vec![then_arm, else_arm]))
         };
@@ -68,6 +73,7 @@ pub(crate) fn replace_if_let_with_match(ctx: AssistCtx) -> Option<Assist> {
 #[cfg(test)]
 mod tests {
     use super::*;
+
     use crate::helpers::{check_assist, check_assist_target};
 
     #[test]
@@ -145,4 +151,64 @@ impl VariantData {
         }",
         );
     }
+
+    #[test]
+    fn special_case_option() {
+        check_assist(
+            replace_if_let_with_match,
+            r#"
+enum Option<T> { Some(T), None }
+use Option::*;
+
+fn foo(x: Option<i32>) {
+    <|>if let Some(x) = x {
+        println!("{}", x)
+    } else {
+        println!("none")
+    }
+}
+           "#,
+            r#"
+enum Option<T> { Some(T), None }
+use Option::*;
+
+fn foo(x: Option<i32>) {
+    <|>match x {
+        Some(x) => println!("{}", x),
+        None => println!("none"),
+    }
+}
+           "#,
+        );
+    }
+
+    #[test]
+    fn special_case_result() {
+        check_assist(
+            replace_if_let_with_match,
+            r#"
+enum Result<T, E> { Ok(T), Err(E) }
+use Result::*;
+
+fn foo(x: Result<i32, ()>) {
+    <|>if let Ok(x) = x {
+        println!("{}", x)
+    } else {
+        println!("none")
+    }
+}
+           "#,
+            r#"
+enum Result<T, E> { Ok(T), Err(E) }
+use Result::*;
+
+fn foo(x: Result<i32, ()>) {
+    <|>match x {
+        Ok(x) => println!("{}", x),
+        Err(_) => println!("none"),
+    }
+}
+           "#,
+        );
+    }
 }
diff --git a/crates/ra_assists/src/handlers/replace_let_with_if_let.rs b/crates/ra_assists/src/handlers/replace_let_with_if_let.rs
index bdbaae389..0cf23b754 100644
--- a/crates/ra_assists/src/handlers/replace_let_with_if_let.rs
+++ b/crates/ra_assists/src/handlers/replace_let_with_if_let.rs
@@ -1,6 +1,5 @@
 use std::iter::once;
 
-use hir::Adt;
 use ra_syntax::{
     ast::{
         self,
@@ -12,6 +11,7 @@ use ra_syntax::{
 
 use crate::{
     assist_ctx::{Assist, AssistCtx},
+    utils::TryEnum,
     AssistId,
 };
 
@@ -45,20 +45,10 @@ pub(crate) fn replace_let_with_if_let(ctx: AssistCtx) -> Option<Assist> {
     let init = let_stmt.initializer()?;
     let original_pat = let_stmt.pat()?;
     let ty = ctx.sema.type_of_expr(&init)?;
-    let enum_ = match ty.as_adt() {
-        Some(Adt::Enum(it)) => it,
-        _ => return None,
-    };
-    let happy_case =
-        [("Result", "Ok"), ("Option", "Some")].iter().find_map(|(known_type, happy_case)| {
-            if &enum_.name(ctx.db).to_string() == known_type {
-                return Some(happy_case);
-            }
-            None
-        });
+    let happy_variant = TryEnum::from_ty(ctx.sema, &ty).map(|it| it.happy_case());
 
     ctx.add_assist(AssistId("replace_let_with_if_let"), "Replace with if-let", |edit| {
-        let with_placeholder: ast::Pat = match happy_case {
+        let with_placeholder: ast::Pat = match happy_variant {
             None => make::placeholder_pat().into(),
             Some(var_name) => make::tuple_struct_pat(
                 make::path_unqualified(make::path_segment(make::name_ref(var_name))),
diff --git a/crates/ra_assists/src/handlers/replace_qualified_name_with_use.rs b/crates/ra_assists/src/handlers/replace_qualified_name_with_use.rs
index 2f02df303..918e8dd8d 100644
--- a/crates/ra_assists/src/handlers/replace_qualified_name_with_use.rs
+++ b/crates/ra_assists/src/handlers/replace_qualified_name_with_use.rs
@@ -27,7 +27,7 @@ pub(crate) fn replace_qualified_name_with_use(ctx: AssistCtx) -> Option<Assist>
         return None;
     }
 
-    let hir_path = hir::Path::from_ast(path.clone())?;
+    let hir_path = ctx.sema.lower_path(&path)?;
     let segments = collect_hir_path_segments(&hir_path)?;
     if segments.len() < 2 {
         return None;
diff --git a/crates/ra_assists/src/handlers/replace_unwrap_with_match.rs b/crates/ra_assists/src/handlers/replace_unwrap_with_match.rs
index 62cb7a763..62d4ea522 100644
--- a/crates/ra_assists/src/handlers/replace_unwrap_with_match.rs
+++ b/crates/ra_assists/src/handlers/replace_unwrap_with_match.rs
@@ -1,12 +1,11 @@
 use std::iter;
 
 use ra_syntax::{
-    ast::{self, make},
+    ast::{self, edit::IndentLevel, make},
     AstNode,
 };
 
-use crate::{Assist, AssistCtx, AssistId};
-use ast::edit::IndentLevel;
+use crate::{utils::TryEnum, Assist, AssistCtx, AssistId};
 
 // Assist: replace_unwrap_with_match
 //
@@ -38,42 +37,27 @@ pub(crate) fn replace_unwrap_with_match(ctx: AssistCtx) -> Option<Assist> {
     }
     let caller = method_call.expr()?;
     let ty = ctx.sema.type_of_expr(&caller)?;
+    let happy_variant = TryEnum::from_ty(ctx.sema, &ty)?.happy_case();
 
-    let type_name = ty.as_adt()?.name(ctx.sema.db).to_string();
+    ctx.add_assist(AssistId("replace_unwrap_with_match"), "Replace unwrap with match", |edit| {
+        let ok_path = make::path_unqualified(make::path_segment(make::name_ref(happy_variant)));
+        let it = make::bind_pat(make::name("a")).into();
+        let ok_tuple = make::tuple_struct_pat(ok_path, iter::once(it)).into();
 
-    for (unwrap_type, variant_name) in [("Result", "Ok"), ("Option", "Some")].iter() {
-        if &type_name == unwrap_type {
-            return ctx.add_assist(
-                AssistId("replace_unwrap_with_match"),
-                "Replace unwrap with match",
-                |edit| {
-                    let ok_path =
-                        make::path_unqualified(make::path_segment(make::name_ref(variant_name)));
-                    let it = make::bind_pat(make::name("a")).into();
-                    let ok_tuple = make::tuple_struct_pat(ok_path, iter::once(it)).into();
+        let bind_path = make::path_unqualified(make::path_segment(make::name_ref("a")));
+        let ok_arm = make::match_arm(iter::once(ok_tuple), make::expr_path(bind_path));
 
-                    let bind_path = make::path_unqualified(make::path_segment(make::name_ref("a")));
-                    let ok_arm = make::match_arm(iter::once(ok_tuple), make::expr_path(bind_path));
+        let unreachable_call = make::unreachable_macro_call().into();
+        let err_arm = make::match_arm(iter::once(make::placeholder_pat().into()), unreachable_call);
 
-                    let unreachable_call = make::unreachable_macro_call().into();
-                    let err_arm = make::match_arm(
-                        iter::once(make::placeholder_pat().into()),
-                        unreachable_call,
-                    );
+        let match_arm_list = make::match_arm_list(vec![ok_arm, err_arm]);
+        let match_expr = make::expr_match(caller.clone(), match_arm_list);
+        let match_expr = IndentLevel::from_node(method_call.syntax()).increase_indent(match_expr);
 
-                    let match_arm_list = make::match_arm_list(vec![ok_arm, err_arm]);
-                    let match_expr = make::expr_match(caller.clone(), match_arm_list);
-                    let match_expr =
-                        IndentLevel::from_node(method_call.syntax()).increase_indent(match_expr);
-
-                    edit.target(method_call.syntax().text_range());
-                    edit.set_cursor(caller.syntax().text_range().start());
-                    edit.replace_ast::<ast::Expr>(method_call.into(), match_expr);
-                },
-            );
-        }
-    }
-    None
+        edit.target(method_call.syntax().text_range());
+        edit.set_cursor(caller.syntax().text_range().start());
+        edit.replace_ast::<ast::Expr>(method_call.into(), match_expr);
+    })
 }
 
 #[cfg(test)]
diff --git a/crates/ra_assists/src/handlers/unwrap_block.rs b/crates/ra_assists/src/handlers/unwrap_block.rs
new file mode 100644
index 000000000..58649c47e
--- /dev/null
+++ b/crates/ra_assists/src/handlers/unwrap_block.rs
@@ -0,0 +1,348 @@
+use crate::{Assist, AssistCtx, AssistId};
+
+use ast::{BlockExpr, Expr, ForExpr, IfExpr, LoopBodyOwner, LoopExpr, WhileExpr};
+use ra_fmt::unwrap_trivial_block;
+use ra_syntax::{ast, AstNode, TextRange, T};
+
+// Assist: unwrap_block
+//
+// This assist removes if...else, for, while and loop control statements to just keep the body.
+//
+// ```
+// fn foo() {
+//     if true {<|>
+//         println!("foo");
+//     }
+// }
+// ```
+// ->
+// ```
+// fn foo() {
+//     println!("foo");
+// }
+// ```
+pub(crate) fn unwrap_block(ctx: AssistCtx) -> Option<Assist> {
+    let l_curly_token = ctx.find_token_at_offset(T!['{'])?;
+
+    let res = if let Some(if_expr) = l_curly_token.ancestors().find_map(IfExpr::cast) {
+        // if expression
+        let expr_to_unwrap = if_expr.blocks().find_map(|expr| extract_expr(ctx.frange.range, expr));
+        let expr_to_unwrap = expr_to_unwrap?;
+        // Find if we are in a else if block
+        let ancestor = if_expr.syntax().ancestors().skip(1).find_map(ast::IfExpr::cast);
+
+        if let Some(ancestor) = ancestor {
+            Some((ast::Expr::IfExpr(ancestor), expr_to_unwrap))
+        } else {
+            Some((ast::Expr::IfExpr(if_expr), expr_to_unwrap))
+        }
+    } else if let Some(for_expr) = l_curly_token.ancestors().find_map(ForExpr::cast) {
+        // for expression
+        let block_expr = for_expr.loop_body()?;
+        extract_expr(ctx.frange.range, block_expr)
+            .map(|expr_to_unwrap| (ast::Expr::ForExpr(for_expr), expr_to_unwrap))
+    } else if let Some(while_expr) = l_curly_token.ancestors().find_map(WhileExpr::cast) {
+        // while expression
+        let block_expr = while_expr.loop_body()?;
+        extract_expr(ctx.frange.range, block_expr)
+            .map(|expr_to_unwrap| (ast::Expr::WhileExpr(while_expr), expr_to_unwrap))
+    } else if let Some(loop_expr) = l_curly_token.ancestors().find_map(LoopExpr::cast) {
+        // loop expression
+        let block_expr = loop_expr.loop_body()?;
+        extract_expr(ctx.frange.range, block_expr)
+            .map(|expr_to_unwrap| (ast::Expr::LoopExpr(loop_expr), expr_to_unwrap))
+    } else {
+        None
+    };
+
+    let (expr, expr_to_unwrap) = res?;
+    ctx.add_assist(AssistId("unwrap_block"), "Unwrap block", |edit| {
+        edit.set_cursor(expr.syntax().text_range().start());
+        edit.target(expr_to_unwrap.syntax().text_range());
+
+        let pat_start: &[_] = &[' ', '{', '\n'];
+        let expr_to_unwrap = expr_to_unwrap.to_string();
+        let expr_string = expr_to_unwrap.trim_start_matches(pat_start);
+        let mut expr_string_lines: Vec<&str> = expr_string.lines().collect();
+        expr_string_lines.pop(); // Delete last line
+
+        let expr_string = expr_string_lines
+            .into_iter()
+            .map(|line| line.replacen("    ", "", 1)) // Delete indentation
+            .collect::<Vec<String>>()
+            .join("\n");
+
+        edit.replace(expr.syntax().text_range(), expr_string);
+    })
+}
+
+fn extract_expr(cursor_range: TextRange, block: BlockExpr) -> Option<Expr> {
+    let cursor_in_range = block.l_curly_token()?.text_range().contains_range(cursor_range);
+
+    if cursor_in_range {
+        Some(unwrap_trivial_block(block))
+    } else {
+        None
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::helpers::{check_assist, check_assist_not_applicable};
+
+    use super::*;
+
+    #[test]
+    fn simple_if() {
+        check_assist(
+            unwrap_block,
+            r#"
+            fn main() {
+                bar();
+                if true {<|>
+                    foo();
+
+                    //comment
+                    bar();
+                } else {
+                    println!("bar");
+                }
+            }
+            "#,
+            r#"
+            fn main() {
+                bar();
+                <|>foo();
+
+                //comment
+                bar();
+            }
+            "#,
+        );
+    }
+
+    #[test]
+    fn simple_if_else() {
+        check_assist(
+            unwrap_block,
+            r#"
+            fn main() {
+                bar();
+                if true {
+                    foo();
+
+                    //comment
+                    bar();
+                } else {<|>
+                    println!("bar");
+                }
+            }
+            "#,
+            r#"
+            fn main() {
+                bar();
+                <|>println!("bar");
+            }
+            "#,
+        );
+    }
+
+    #[test]
+    fn simple_if_else_if() {
+        check_assist(
+            unwrap_block,
+            r#"
+            fn main() {
+                //bar();
+                if true {
+                    println!("true");
+
+                    //comment
+                    //bar();
+                } else if false {<|>
+                    println!("bar");
+                } else {
+                    println!("foo");
+                }
+            }
+            "#,
+            r#"
+            fn main() {
+                //bar();
+                <|>println!("bar");
+            }
+            "#,
+        );
+    }
+
+    #[test]
+    fn simple_if_bad_cursor_position() {
+        check_assist_not_applicable(
+            unwrap_block,
+            r#"
+            fn main() {
+                bar();<|>
+                if true {
+                    foo();
+
+                    //comment
+                    bar();
+                } else {
+                    println!("bar");
+                }
+            }
+            "#,
+        );
+    }
+
+    #[test]
+    fn simple_for() {
+        check_assist(
+            unwrap_block,
+            r#"
+            fn main() {
+                for i in 0..5 {<|>
+                    if true {
+                        foo();
+
+                        //comment
+                        bar();
+                    } else {
+                        println!("bar");
+                    }
+                }
+            }
+            "#,
+            r#"
+            fn main() {
+                <|>if true {
+                    foo();
+
+                    //comment
+                    bar();
+                } else {
+                    println!("bar");
+                }
+            }
+            "#,
+        );
+    }
+
+    #[test]
+    fn simple_if_in_for() {
+        check_assist(
+            unwrap_block,
+            r#"
+            fn main() {
+                for i in 0..5 {
+                    if true {<|>
+                        foo();
+
+                        //comment
+                        bar();
+                    } else {
+                        println!("bar");
+                    }
+                }
+            }
+            "#,
+            r#"
+            fn main() {
+                for i in 0..5 {
+                    <|>foo();
+
+                    //comment
+                    bar();
+                }
+            }
+            "#,
+        );
+    }
+
+    #[test]
+    fn simple_loop() {
+        check_assist(
+            unwrap_block,
+            r#"
+            fn main() {
+                loop {<|>
+                    if true {
+                        foo();
+
+                        //comment
+                        bar();
+                    } else {
+                        println!("bar");
+                    }
+                }
+            }
+            "#,
+            r#"
+            fn main() {
+                <|>if true {
+                    foo();
+
+                    //comment
+                    bar();
+                } else {
+                    println!("bar");
+                }
+            }
+            "#,
+        );
+    }
+
+    #[test]
+    fn simple_while() {
+        check_assist(
+            unwrap_block,
+            r#"
+            fn main() {
+                while true {<|>
+                    if true {
+                        foo();
+
+                        //comment
+                        bar();
+                    } else {
+                        println!("bar");
+                    }
+                }
+            }
+            "#,
+            r#"
+            fn main() {
+                <|>if true {
+                    foo();
+
+                    //comment
+                    bar();
+                } else {
+                    println!("bar");
+                }
+            }
+            "#,
+        );
+    }
+
+    #[test]
+    fn simple_if_in_while_bad_cursor_position() {
+        check_assist_not_applicable(
+            unwrap_block,
+            r#"
+            fn main() {
+                while true {
+                    if true {
+                        foo();<|>
+
+                        //comment
+                        bar();
+                    } else {
+                        println!("bar");
+                    }
+                }
+            }
+            "#,
+        );
+    }
+}
diff --git a/crates/ra_assists/src/lib.rs b/crates/ra_assists/src/lib.rs
index 64bd87afb..c5df86600 100644
--- a/crates/ra_assists/src/lib.rs
+++ b/crates/ra_assists/src/lib.rs
@@ -143,6 +143,7 @@ mod handlers {
     mod split_import;
     mod add_from_impl_for_enum;
     mod reorder_fields;
+    mod unwrap_block;
 
     pub(crate) fn all() -> &'static [AssistHandler] {
         &[
@@ -181,6 +182,7 @@ mod handlers {
             replace_unwrap_with_match::replace_unwrap_with_match,
             split_import::split_import,
             add_from_impl_for_enum::add_from_impl_for_enum,
+            unwrap_block::unwrap_block,
             // These are manually sorted for better priorities
             add_missing_impl_members::add_missing_impl_members,
             add_missing_impl_members::add_missing_default_members,
diff --git a/crates/ra_assists/src/marks.rs b/crates/ra_assists/src/marks.rs
index 6c2a2b8b6..8d910205f 100644
--- a/crates/ra_assists/src/marks.rs
+++ b/crates/ra_assists/src/marks.rs
@@ -8,4 +8,5 @@ test_utils::marks![
     test_not_inline_mut_variable
     test_not_applicable_if_variable_unused
     change_visibility_field_false_positive
+    test_add_from_impl_already_exists
 ];
diff --git a/crates/ra_assists/src/utils.rs b/crates/ra_assists/src/utils.rs
index 3d6c59bda..efd988697 100644
--- a/crates/ra_assists/src/utils.rs
+++ b/crates/ra_assists/src/utils.rs
@@ -1,7 +1,9 @@
 //! Assorted functions shared by several assists.
 pub(crate) mod insert_use;
 
-use hir::Semantics;
+use std::iter;
+
+use hir::{Adt, Crate, Semantics, Trait, Type};
 use ra_ide_db::RootDatabase;
 use ra_syntax::{
     ast::{self, make, NameOwner},
@@ -99,3 +101,109 @@ fn invert_special_case(expr: &ast::Expr) -> Option<ast::Expr> {
         _ => None,
     }
 }
+
+#[derive(Clone, Copy)]
+pub(crate) enum TryEnum {
+    Result,
+    Option,
+}
+
+impl TryEnum {
+    const ALL: [TryEnum; 2] = [TryEnum::Option, TryEnum::Result];
+
+    pub(crate) fn from_ty(sema: &Semantics<RootDatabase>, ty: &Type) -> Option<TryEnum> {
+        let enum_ = match ty.as_adt() {
+            Some(Adt::Enum(it)) => it,
+            _ => return None,
+        };
+        TryEnum::ALL.iter().find_map(|&var| {
+            if &enum_.name(sema.db).to_string() == var.type_name() {
+                return Some(var);
+            }
+            None
+        })
+    }
+
+    pub(crate) fn happy_case(self) -> &'static str {
+        match self {
+            TryEnum::Result => "Ok",
+            TryEnum::Option => "Some",
+        }
+    }
+
+    pub(crate) fn sad_pattern(self) -> ast::Pat {
+        match self {
+            TryEnum::Result => make::tuple_struct_pat(
+                make::path_unqualified(make::path_segment(make::name_ref("Err"))),
+                iter::once(make::placeholder_pat().into()),
+            )
+            .into(),
+            TryEnum::Option => make::bind_pat(make::name("None")).into(),
+        }
+    }
+
+    fn type_name(self) -> &'static str {
+        match self {
+            TryEnum::Result => "Result",
+            TryEnum::Option => "Option",
+        }
+    }
+}
+
+/// Helps with finding well-know things inside the standard library. This is
+/// somewhat similar to the known paths infra inside hir, but it different; We
+/// want to make sure that IDE specific paths don't become interesting inside
+/// the compiler itself as well.
+pub(crate) struct FamousDefs<'a, 'b>(pub(crate) &'a Semantics<'b, RootDatabase>, pub(crate) Crate);
+
+#[allow(non_snake_case)]
+impl FamousDefs<'_, '_> {
+    #[cfg(test)]
+    pub(crate) const FIXTURE: &'static str = r#"
+//- /libcore.rs crate:core
+pub mod convert{
+    pub trait From<T> {
+        fn from(T) -> Self;
+    }
+}
+
+pub mod prelude { pub use crate::convert::From }
+#[prelude_import]
+pub use prelude::*;
+"#;
+
+    pub(crate) fn core_convert_From(&self) -> Option<Trait> {
+        self.find_trait("core:convert:From")
+    }
+
+    fn find_trait(&self, path: &str) -> Option<Trait> {
+        let db = self.0.db;
+        let mut path = path.split(':');
+        let trait_ = path.next_back()?;
+        let std_crate = path.next()?;
+        let std_crate = self
+            .1
+            .dependencies(db)
+            .into_iter()
+            .find(|dep| &dep.name.to_string() == std_crate)?
+            .krate;
+
+        let mut module = std_crate.root_module(db)?;
+        for segment in path {
+            module = module.children(db).find_map(|child| {
+                let name = child.name(db)?;
+                if &name.to_string() == segment {
+                    Some(child)
+                } else {
+                    None
+                }
+            })?;
+        }
+        let def =
+            module.scope(db, None).into_iter().find(|(name, _def)| &name.to_string() == trait_)?.1;
+        match def {
+            hir::ScopeDef::ModuleDef(hir::ModuleDef::Trait(it)) => Some(it),
+            _ => None,
+        }
+    }
+}
diff --git a/crates/ra_flycheck/Cargo.toml b/crates/ra_flycheck/Cargo.toml
index 76e5cada4..324c33d9d 100644
--- a/crates/ra_flycheck/Cargo.toml
+++ b/crates/ra_flycheck/Cargo.toml
@@ -6,7 +6,7 @@ authors = ["rust-analyzer developers"]
 
 [dependencies]
 crossbeam-channel = "0.4.0"
-lsp-types = { version = "0.73.0", features = ["proposed"] }
+lsp-types = { version = "0.74.0", features = ["proposed"] }
 log = "0.4.8"
 cargo_metadata = "0.9.1"
 serde_json = "1.0.48"
diff --git a/crates/ra_fmt/src/lib.rs b/crates/ra_fmt/src/lib.rs
index 0b4ba1bbe..f910ded9d 100644
--- a/crates/ra_fmt/src/lib.rs
+++ b/crates/ra_fmt/src/lib.rs
@@ -42,7 +42,6 @@ pub fn unwrap_trivial_block(block: ast::BlockExpr) -> ast::Expr {
 }
 
 pub fn extract_trivial_expression(block: &ast::BlockExpr) -> Option<ast::Expr> {
-    let block = block.block()?;
     let has_anything_else = |thing: &SyntaxNode| -> bool {
         let mut non_trivial_children =
             block.syntax().children_with_tokens().filter(|it| match it.kind() {
@@ -57,18 +56,17 @@ pub fn extract_trivial_expression(block: &ast::BlockExpr) -> Option<ast::Expr> {
             return None;
         }
         return Some(expr);
-    } else {
-        // Unwrap `{ continue; }`
-        let (stmt,) = block.statements().next_tuple()?;
-        if let ast::Stmt::ExprStmt(expr_stmt) = stmt {
-            if has_anything_else(expr_stmt.syntax()) {
-                return None;
-            }
-            let expr = expr_stmt.expr()?;
-            match expr.syntax().kind() {
-                CONTINUE_EXPR | BREAK_EXPR | RETURN_EXPR => return Some(expr),
-                _ => (),
-            }
+    }
+    // Unwrap `{ continue; }`
+    let (stmt,) = block.statements().next_tuple()?;
+    if let ast::Stmt::ExprStmt(expr_stmt) = stmt {
+        if has_anything_else(expr_stmt.syntax()) {
+            return None;
+        }
+        let expr = expr_stmt.expr()?;
+        match expr.syntax().kind() {
+            CONTINUE_EXPR | BREAK_EXPR | RETURN_EXPR => return Some(expr),
+            _ => (),
         }
     }
     None
diff --git a/crates/ra_hir/src/code_model.rs b/crates/ra_hir/src/code_model.rs
index fb788736d..af59aa1b6 100644
--- a/crates/ra_hir/src/code_model.rs
+++ b/crates/ra_hir/src/code_model.rs
@@ -953,6 +953,16 @@ impl TypeParam {
     pub fn module(self, db: &dyn HirDatabase) -> Module {
         self.id.parent.module(db.upcast()).into()
     }
+
+    pub fn ty(self, db: &dyn HirDatabase) -> Type {
+        let resolver = self.id.parent.resolver(db.upcast());
+        let environment = TraitEnvironment::lower(db, &resolver);
+        let ty = Ty::Placeholder(self.id);
+        Type {
+            krate: self.id.parent.module(db.upcast()).krate,
+            ty: InEnvironment { value: ty, environment },
+        }
+    }
 }
 
 // FIXME: rename from `ImplDef` to `Impl`
@@ -1157,18 +1167,21 @@ impl Type {
 
     pub fn fields(&self, db: &dyn HirDatabase) -> Vec<(Field, Type)> {
         if let Ty::Apply(a_ty) = &self.ty.value {
-            if let TypeCtor::Adt(AdtId::StructId(s)) = a_ty.ctor {
-                let var_def = s.into();
-                return db
-                    .field_types(var_def)
-                    .iter()
-                    .map(|(local_id, ty)| {
-                        let def = Field { parent: var_def.into(), id: local_id };
-                        let ty = ty.clone().subst(&a_ty.parameters);
-                        (def, self.derived(ty))
-                    })
-                    .collect();
-            }
+            let variant_id = match a_ty.ctor {
+                TypeCtor::Adt(AdtId::StructId(s)) => s.into(),
+                TypeCtor::Adt(AdtId::UnionId(u)) => u.into(),
+                _ => return Vec::new(),
+            };
+
+            return db
+                .field_types(variant_id)
+                .iter()
+                .map(|(local_id, ty)| {
+                    let def = Field { parent: variant_id.into(), id: local_id };
+                    let ty = ty.clone().subst(&a_ty.parameters);
+                    (def, self.derived(ty))
+                })
+                .collect();
         };
         Vec::new()
     }
diff --git a/crates/ra_hir/src/lib.rs b/crates/ra_hir/src/lib.rs
index 312ef3814..c5df4ac24 100644
--- a/crates/ra_hir/src/lib.rs
+++ b/crates/ra_hir/src/lib.rs
@@ -70,6 +70,7 @@ pub use hir_def::{
     type_ref::Mutability,
 };
 pub use hir_expand::{
-    name::Name, HirFileId, InFile, MacroCallId, MacroCallLoc, MacroDefId, MacroFile, Origin,
+    hygiene::Hygiene, name::Name, HirFileId, InFile, MacroCallId, MacroCallLoc, MacroDefId,
+    MacroFile, Origin,
 };
 pub use hir_ty::{display::HirDisplay, CallableDef};
diff --git a/crates/ra_hir/src/semantics.rs b/crates/ra_hir/src/semantics.rs
index 86bfb416c..515e5eb17 100644
--- a/crates/ra_hir/src/semantics.rs
+++ b/crates/ra_hir/src/semantics.rs
@@ -8,7 +8,8 @@ use hir_def::{
     resolver::{self, HasResolver, Resolver},
     AsMacroCall, TraitId,
 };
-use hir_expand::ExpansionInfo;
+use hir_expand::{hygiene::Hygiene, ExpansionInfo};
+use hir_ty::associated_type_shorthand_candidates;
 use itertools::Itertools;
 use ra_db::{FileId, FileRange};
 use ra_prof::profile;
@@ -24,8 +25,9 @@ use crate::{
     semantics::source_to_def::{ChildContainer, SourceToDefCache, SourceToDefCtx},
     source_analyzer::{resolve_hir_path, SourceAnalyzer},
     AssocItem, Field, Function, HirFileId, ImplDef, InFile, Local, MacroDef, Module, ModuleDef,
-    Name, Origin, Path, ScopeDef, Trait, Type, TypeParam,
+    Name, Origin, Path, ScopeDef, Trait, Type, TypeAlias, TypeParam,
 };
+use resolver::TypeNs;
 
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub enum PathResolution {
@@ -40,6 +42,44 @@ pub enum PathResolution {
     AssocItem(AssocItem),
 }
 
+impl PathResolution {
+    fn in_type_ns(&self) -> Option<TypeNs> {
+        match self {
+            PathResolution::Def(ModuleDef::Adt(adt)) => Some(TypeNs::AdtId((*adt).into())),
+            PathResolution::Def(ModuleDef::BuiltinType(builtin)) => {
+                Some(TypeNs::BuiltinType(*builtin))
+            }
+            PathResolution::Def(ModuleDef::Const(_))
+            | PathResolution::Def(ModuleDef::EnumVariant(_))
+            | PathResolution::Def(ModuleDef::Function(_))
+            | PathResolution::Def(ModuleDef::Module(_))
+            | PathResolution::Def(ModuleDef::Static(_))
+            | PathResolution::Def(ModuleDef::Trait(_)) => None,
+            PathResolution::Def(ModuleDef::TypeAlias(alias)) => {
+                Some(TypeNs::TypeAliasId((*alias).into()))
+            }
+            PathResolution::Local(_) | PathResolution::Macro(_) => None,
+            PathResolution::TypeParam(param) => Some(TypeNs::GenericParam((*param).into())),
+            PathResolution::SelfType(impl_def) => Some(TypeNs::SelfType((*impl_def).into())),
+            PathResolution::AssocItem(AssocItem::Const(_))
+            | PathResolution::AssocItem(AssocItem::Function(_)) => None,
+            PathResolution::AssocItem(AssocItem::TypeAlias(alias)) => {
+                Some(TypeNs::TypeAliasId((*alias).into()))
+            }
+        }
+    }
+
+    /// Returns an iterator over associated types that may be specified after this path (using
+    /// `Ty::Assoc` syntax).
+    pub fn assoc_type_shorthand_candidates<R>(
+        &self,
+        db: &dyn HirDatabase,
+        mut cb: impl FnMut(TypeAlias) -> Option<R>,
+    ) -> Option<R> {
+        associated_type_shorthand_candidates(db, self.in_type_ns()?, |_, _, id| cb(id.into()))
+    }
+}
+
 /// Primary API to get semantic information, like types, from syntax trees.
 pub struct Semantics<'db, DB> {
     pub db: &'db DB,
@@ -206,6 +246,11 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
         self.analyze(path.syntax()).resolve_path(self.db, path)
     }
 
+    pub fn lower_path(&self, path: &ast::Path) -> Option<Path> {
+        let src = self.find_file(path.syntax().clone());
+        Path::from_src(path.clone(), &Hygiene::new(self.db.upcast(), src.file_id.into()))
+    }
+
     pub fn resolve_bind_pat_to_const(&self, pat: &ast::BindPat) -> Option<ModuleDef> {
         self.analyze(pat.syntax()).resolve_bind_pat_to_const(self.db, pat)
     }
diff --git a/crates/ra_hir/src/semantics/source_to_def.rs b/crates/ra_hir/src/semantics/source_to_def.rs
index 6f3b5b2da..8af64fdc1 100644
--- a/crates/ra_hir/src/semantics/source_to_def.rs
+++ b/crates/ra_hir/src/semantics/source_to_def.rs
@@ -151,7 +151,7 @@ impl SourceToDefCtx<'_, '_> {
         let krate = self.file_to_def(file_id)?.krate;
         let file_ast_id = self.db.ast_id_map(src.file_id).ast_id(&src.value);
         let ast_id = Some(AstId::new(src.file_id, file_ast_id));
-        Some(MacroDefId { krate: Some(krate), ast_id, kind })
+        Some(MacroDefId { krate: Some(krate), ast_id, kind, local_inner: false })
     }
 
     pub(super) fn find_container(&mut self, src: InFile<&SyntaxNode>) -> Option<ChildContainer> {
diff --git a/crates/ra_hir/src/source_analyzer.rs b/crates/ra_hir/src/source_analyzer.rs
index 74d64c97d..c63d1b847 100644
--- a/crates/ra_hir/src/source_analyzer.rs
+++ b/crates/ra_hir/src/source_analyzer.rs
@@ -224,7 +224,8 @@ impl SourceAnalyzer {
             }
         }
         // This must be a normal source file rather than macro file.
-        let hir_path = crate::Path::from_ast(path.clone())?;
+        let hir_path =
+            crate::Path::from_src(path.clone(), &Hygiene::new(db.upcast(), self.file_id))?;
         resolve_hir_path(db, &self.resolver, &hir_path)
     }
 
diff --git a/crates/ra_hir_def/src/adt.rs b/crates/ra_hir_def/src/adt.rs
index 753becc3d..8eef51828 100644
--- a/crates/ra_hir_def/src/adt.rs
+++ b/crates/ra_hir_def/src/adt.rs
@@ -12,9 +12,15 @@ use ra_prof::profile;
 use ra_syntax::ast::{self, NameOwner, TypeAscriptionOwner, VisibilityOwner};
 
 use crate::{
-    body::CfgExpander, db::DefDatabase, src::HasChildSource, src::HasSource, trace::Trace,
-    type_ref::TypeRef, visibility::RawVisibility, EnumId, HasModule, LocalEnumVariantId,
-    LocalFieldId, Lookup, ModuleId, StructId, UnionId, VariantId,
+    body::{CfgExpander, LowerCtx},
+    db::DefDatabase,
+    src::HasChildSource,
+    src::HasSource,
+    trace::Trace,
+    type_ref::TypeRef,
+    visibility::RawVisibility,
+    EnumId, HasModule, LocalEnumVariantId, LocalFieldId, Lookup, ModuleId, StructId, UnionId,
+    VariantId,
 };
 
 /// Note that we use `StructData` for unions as well!
@@ -198,6 +204,8 @@ fn lower_struct(
     trace: &mut Trace<FieldData, Either<ast::TupleFieldDef, ast::RecordFieldDef>>,
     ast: &InFile<ast::StructKind>,
 ) -> StructKind {
+    let ctx = LowerCtx::new(db, ast.file_id);
+
     match &ast.value {
         ast::StructKind::Tuple(fl) => {
             for (i, fd) in fl.fields().enumerate() {
@@ -210,7 +218,7 @@ fn lower_struct(
                     || Either::Left(fd.clone()),
                     || FieldData {
                         name: Name::new_tuple_field(i),
-                        type_ref: TypeRef::from_ast_opt(fd.type_ref()),
+                        type_ref: TypeRef::from_ast_opt(&ctx, fd.type_ref()),
                         visibility: RawVisibility::from_ast(db, ast.with_value(fd.visibility())),
                     },
                 );
@@ -228,7 +236,7 @@ fn lower_struct(
                     || Either::Right(fd.clone()),
                     || FieldData {
                         name: fd.name().map(|n| n.as_name()).unwrap_or_else(Name::missing),
-                        type_ref: TypeRef::from_ast_opt(fd.ascribed_type()),
+                        type_ref: TypeRef::from_ast_opt(&ctx, fd.ascribed_type()),
                         visibility: RawVisibility::from_ast(db, ast.with_value(fd.visibility())),
                     },
                 );
diff --git a/crates/ra_hir_def/src/attr.rs b/crates/ra_hir_def/src/attr.rs
index 5a86af8ba..576cd0c65 100644
--- a/crates/ra_hir_def/src/attr.rs
+++ b/crates/ra_hir_def/src/attr.rs
@@ -140,6 +140,7 @@ impl Attr {
     }
 }
 
+#[derive(Debug, Clone, Copy)]
 pub struct AttrQuery<'a> {
     attrs: &'a Attrs,
     key: &'static str,
diff --git a/crates/ra_hir_def/src/body.rs b/crates/ra_hir_def/src/body.rs
index 890cefcaf..4edaad960 100644
--- a/crates/ra_hir_def/src/body.rs
+++ b/crates/ra_hir_def/src/body.rs
@@ -15,6 +15,8 @@ use ra_prof::profile;
 use ra_syntax::{ast, AstNode, AstPtr};
 use rustc_hash::FxHashMap;
 
+pub(crate) use lower::LowerCtx;
+
 use crate::{
     attr::Attrs,
     db::DefDatabase,
diff --git a/crates/ra_hir_def/src/body/lower.rs b/crates/ra_hir_def/src/body/lower.rs
index 571603854..687216dc3 100644
--- a/crates/ra_hir_def/src/body/lower.rs
+++ b/crates/ra_hir_def/src/body/lower.rs
@@ -3,8 +3,9 @@
 
 use either::Either;
 use hir_expand::{
+    hygiene::Hygiene,
     name::{name, AsName, Name},
-    MacroDefId, MacroDefKind,
+    HirFileId, MacroDefId, MacroDefKind,
 };
 use ra_arena::Arena;
 use ra_syntax::{
@@ -26,7 +27,7 @@ use crate::{
         LogicOp, MatchArm, Ordering, Pat, PatId, RecordFieldPat, RecordLitField, Statement,
     },
     item_scope::BuiltinShadowMode,
-    path::GenericArgs,
+    path::{GenericArgs, Path},
     type_ref::{Mutability, TypeRef},
     AdtId, ConstLoc, ContainerId, DefWithBodyId, EnumLoc, FunctionLoc, Intern, ModuleDefId,
     StaticLoc, StructLoc, TraitLoc, TypeAliasLoc, UnionLoc,
@@ -35,6 +36,23 @@ use crate::{
 use super::{ExprSource, PatSource};
 use ast::AstChildren;
 
+pub(crate) struct LowerCtx {
+    hygiene: Hygiene,
+}
+
+impl LowerCtx {
+    pub fn new(db: &dyn DefDatabase, file_id: HirFileId) -> Self {
+        LowerCtx { hygiene: Hygiene::new(db.upcast(), file_id) }
+    }
+    pub fn with_hygiene(hygiene: &Hygiene) -> Self {
+        LowerCtx { hygiene: hygiene.clone() }
+    }
+
+    pub fn lower_path(&self, ast: ast::Path) -> Option<Path> {
+        Path::from_src(ast, &self.hygiene)
+    }
+}
+
 pub(super) fn lower(
     db: &dyn DefDatabase,
     def: DefWithBodyId,
@@ -42,10 +60,13 @@ pub(super) fn lower(
     params: Option<ast::ParamList>,
     body: Option<ast::Expr>,
 ) -> (Body, BodySourceMap) {
+    let ctx = LowerCtx::new(db, expander.current_file_id.clone());
+
     ExprCollector {
         db,
         def,
         expander,
+        ctx,
         source_map: BodySourceMap::default(),
         body: Body {
             exprs: Arena::default(),
@@ -62,7 +83,7 @@ struct ExprCollector<'a> {
     db: &'a dyn DefDatabase,
     def: DefWithBodyId,
     expander: Expander,
-
+    ctx: LowerCtx,
     body: Body,
     source_map: BodySourceMap,
 }
@@ -182,10 +203,16 @@ impl ExprCollector<'_> {
 
                 self.alloc_expr(Expr::If { condition, then_branch, else_branch }, syntax_ptr)
             }
-            ast::Expr::TryBlockExpr(e) => {
-                let body = self.collect_block_opt(e.body());
-                self.alloc_expr(Expr::TryBlock { body }, syntax_ptr)
-            }
+            ast::Expr::EffectExpr(e) => match e.effect() {
+                ast::Effect::Try(_) => {
+                    let body = self.collect_block_opt(e.block_expr());
+                    self.alloc_expr(Expr::TryBlock { body }, syntax_ptr)
+                }
+                // FIXME: we need to record these effects somewhere...
+                ast::Effect::Async(_) | ast::Effect::Label(_) | ast::Effect::Unsafe(_) => {
+                    self.collect_block_opt(e.block_expr())
+                }
+            },
             ast::Expr::BlockExpr(e) => self.collect_block(e),
             ast::Expr::LoopExpr(e) => {
                 let body = self.collect_block_opt(e.loop_body());
@@ -241,7 +268,8 @@ impl ExprCollector<'_> {
                     Vec::new()
                 };
                 let method_name = e.name_ref().map(|nr| nr.as_name()).unwrap_or_else(Name::missing);
-                let generic_args = e.type_arg_list().and_then(GenericArgs::from_ast);
+                let generic_args =
+                    e.type_arg_list().and_then(|it| GenericArgs::from_ast(&self.ctx, it));
                 self.alloc_expr(
                     Expr::MethodCall { receiver, method_name, args, generic_args },
                     syntax_ptr,
@@ -347,7 +375,7 @@ impl ExprCollector<'_> {
             }
             ast::Expr::CastExpr(e) => {
                 let expr = self.collect_expr_opt(e.expr());
-                let type_ref = TypeRef::from_ast_opt(e.type_ref());
+                let type_ref = TypeRef::from_ast_opt(&self.ctx, e.type_ref());
                 self.alloc_expr(Expr::Cast { expr, type_ref }, syntax_ptr)
             }
             ast::Expr::RefExpr(e) => {
@@ -369,12 +397,16 @@ impl ExprCollector<'_> {
                 if let Some(pl) = e.param_list() {
                     for param in pl.params() {
                         let pat = self.collect_pat_opt(param.pat());
-                        let type_ref = param.ascribed_type().map(TypeRef::from_ast);
+                        let type_ref =
+                            param.ascribed_type().map(|it| TypeRef::from_ast(&self.ctx, it));
                         args.push(pat);
                         arg_types.push(type_ref);
                     }
                 }
-                let ret_type = e.ret_type().and_then(|r| r.type_ref()).map(TypeRef::from_ast);
+                let ret_type = e
+                    .ret_type()
+                    .and_then(|r| r.type_ref())
+                    .map(|it| TypeRef::from_ast(&self.ctx, it));
                 let body = self.collect_expr_opt(e.body());
                 self.alloc_expr(Expr::Lambda { args, arg_types, ret_type, body }, syntax_ptr)
             }
@@ -434,6 +466,7 @@ impl ExprCollector<'_> {
                         krate: Some(self.expander.module.krate),
                         ast_id: Some(self.expander.ast_id(&e)),
                         kind: MacroDefKind::Declarative,
+                        local_inner: false,
                     };
                     self.body.item_scope.define_legacy_macro(name, mac);
 
@@ -468,19 +501,15 @@ impl ExprCollector<'_> {
         }
     }
 
-    fn collect_block(&mut self, expr: ast::BlockExpr) -> ExprId {
-        let syntax_node_ptr = AstPtr::new(&expr.clone().into());
-        let block = match expr.block() {
-            Some(block) => block,
-            None => return self.alloc_expr(Expr::Missing, syntax_node_ptr),
-        };
+    fn collect_block(&mut self, block: ast::BlockExpr) -> ExprId {
+        let syntax_node_ptr = AstPtr::new(&block.clone().into());
         self.collect_block_items(&block);
         let statements = block
             .statements()
             .map(|s| match s {
                 ast::Stmt::LetStmt(stmt) => {
                     let pat = self.collect_pat_opt(stmt.pat());
-                    let type_ref = stmt.ascribed_type().map(TypeRef::from_ast);
+                    let type_ref = stmt.ascribed_type().map(|it| TypeRef::from_ast(&self.ctx, it));
                     let initializer = stmt.initializer().map(|e| self.collect_expr(e));
                     Statement::Let { pat, type_ref, initializer }
                 }
@@ -491,7 +520,7 @@ impl ExprCollector<'_> {
         self.alloc_expr(Expr::Block { statements, tail }, syntax_node_ptr)
     }
 
-    fn collect_block_items(&mut self, block: &ast::Block) {
+    fn collect_block_items(&mut self, block: &ast::BlockExpr) {
         let container = ContainerId::DefWithBodyId(self.def);
         for item in block.items() {
             let (def, name): (ModuleDefId, Option<ast::Name>) = match item {
diff --git a/crates/ra_hir_def/src/data.rs b/crates/ra_hir_def/src/data.rs
index ccb682f9a..7a2067e49 100644
--- a/crates/ra_hir_def/src/data.rs
+++ b/crates/ra_hir_def/src/data.rs
@@ -15,6 +15,7 @@ use ra_syntax::ast::{
 
 use crate::{
     attr::Attrs,
+    body::LowerCtx,
     db::DefDatabase,
     path::{path, AssociatedTypeBinding, GenericArgs, Path},
     src::HasSource,
@@ -40,13 +41,14 @@ impl FunctionData {
     pub(crate) fn fn_data_query(db: &impl DefDatabase, func: FunctionId) -> Arc<FunctionData> {
         let loc = func.lookup(db);
         let src = loc.source(db);
+        let ctx = LowerCtx::new(db, src.file_id);
         let name = src.value.name().map(|n| n.as_name()).unwrap_or_else(Name::missing);
         let mut params = Vec::new();
         let mut has_self_param = false;
         if let Some(param_list) = src.value.param_list() {
             if let Some(self_param) = param_list.self_param() {
                 let self_type = if let Some(type_ref) = self_param.ascribed_type() {
-                    TypeRef::from_ast(type_ref)
+                    TypeRef::from_ast(&ctx, type_ref)
                 } else {
                     let self_type = TypeRef::Path(name![Self].into());
                     match self_param.kind() {
@@ -63,14 +65,14 @@ impl FunctionData {
                 has_self_param = true;
             }
             for param in param_list.params() {
-                let type_ref = TypeRef::from_ast_opt(param.ascribed_type());
+                let type_ref = TypeRef::from_ast_opt(&ctx, param.ascribed_type());
                 params.push(type_ref);
             }
         }
         let attrs = Attrs::new(&src.value, &Hygiene::new(db.upcast(), src.file_id));
 
         let ret_type = if let Some(type_ref) = src.value.ret_type().and_then(|rt| rt.type_ref()) {
-            TypeRef::from_ast(type_ref)
+            TypeRef::from_ast(&ctx, type_ref)
         } else {
             TypeRef::unit()
         };
@@ -122,7 +124,8 @@ impl TypeAliasData {
         let loc = typ.lookup(db);
         let node = loc.source(db);
         let name = node.value.name().map_or_else(Name::missing, |n| n.as_name());
-        let type_ref = node.value.type_ref().map(TypeRef::from_ast);
+        let lower_ctx = LowerCtx::new(db, node.file_id);
+        let type_ref = node.value.type_ref().map(|it| TypeRef::from_ast(&lower_ctx, it));
         let vis_default = RawVisibility::default_for_container(loc.container);
         let visibility = RawVisibility::from_ast_with_default(
             db,
@@ -130,7 +133,7 @@ impl TypeAliasData {
             node.as_ref().map(|n| n.visibility()),
         );
         let bounds = if let Some(bound_list) = node.value.type_bound_list() {
-            bound_list.bounds().map(TypeBound::from_ast).collect()
+            bound_list.bounds().map(|it| TypeBound::from_ast(&lower_ctx, it)).collect()
         } else {
             Vec::new()
         };
@@ -223,9 +226,10 @@ impl ImplData {
         let _p = profile("impl_data_query");
         let impl_loc = id.lookup(db);
         let src = impl_loc.source(db);
+        let lower_ctx = LowerCtx::new(db, src.file_id);
 
-        let target_trait = src.value.target_trait().map(TypeRef::from_ast);
-        let target_type = TypeRef::from_ast_opt(src.value.target_type());
+        let target_trait = src.value.target_trait().map(|it| TypeRef::from_ast(&lower_ctx, it));
+        let target_type = TypeRef::from_ast_opt(&lower_ctx, src.value.target_type());
         let is_negative = src.value.excl_token().is_some();
         let module_id = impl_loc.container.module(db);
 
@@ -279,8 +283,9 @@ impl ConstData {
         vis_default: RawVisibility,
         node: InFile<N>,
     ) -> ConstData {
+        let ctx = LowerCtx::new(db, node.file_id);
         let name = node.value.name().map(|n| n.as_name());
-        let type_ref = TypeRef::from_ast_opt(node.value.ascribed_type());
+        let type_ref = TypeRef::from_ast_opt(&ctx, node.value.ascribed_type());
         let visibility =
             RawVisibility::from_ast_with_default(db, vis_default, node.map(|n| n.visibility()));
         ConstData { name, type_ref, visibility }
diff --git a/crates/ra_hir_def/src/generics.rs b/crates/ra_hir_def/src/generics.rs
index d850244c4..09a5241f7 100644
--- a/crates/ra_hir_def/src/generics.rs
+++ b/crates/ra_hir_def/src/generics.rs
@@ -15,6 +15,7 @@ use ra_prof::profile;
 use ra_syntax::ast::{self, NameOwner, TypeBoundsOwner, TypeParamsOwner};
 
 use crate::{
+    body::LowerCtx,
     child_by_source::ChildBySource,
     db::DefDatabase,
     dyn_map::DynMap,
@@ -80,11 +81,13 @@ impl GenericParams {
     fn new(db: &dyn DefDatabase, def: GenericDefId) -> (GenericParams, InFile<SourceMap>) {
         let mut generics = GenericParams { types: Arena::default(), where_predicates: Vec::new() };
         let mut sm = ArenaMap::default();
+
         // FIXME: add `: Sized` bound for everything except for `Self` in traits
         let file_id = match def {
             GenericDefId::FunctionId(it) => {
                 let src = it.lookup(db).source(db);
-                generics.fill(&mut sm, &src.value);
+                let lower_ctx = LowerCtx::new(db, src.file_id);
+                generics.fill(&lower_ctx, &mut sm, &src.value);
                 // lower `impl Trait` in arguments
                 let data = db.function_data(it);
                 for param in &data.params {
@@ -94,21 +97,25 @@ impl GenericParams {
             }
             GenericDefId::AdtId(AdtId::StructId(it)) => {
                 let src = it.lookup(db).source(db);
-                generics.fill(&mut sm, &src.value);
+                let lower_ctx = LowerCtx::new(db, src.file_id);
+                generics.fill(&lower_ctx, &mut sm, &src.value);
                 src.file_id
             }
             GenericDefId::AdtId(AdtId::UnionId(it)) => {
                 let src = it.lookup(db).source(db);
-                generics.fill(&mut sm, &src.value);
+                let lower_ctx = LowerCtx::new(db, src.file_id);
+                generics.fill(&lower_ctx, &mut sm, &src.value);
                 src.file_id
             }
             GenericDefId::AdtId(AdtId::EnumId(it)) => {
                 let src = it.lookup(db).source(db);
-                generics.fill(&mut sm, &src.value);
+                let lower_ctx = LowerCtx::new(db, src.file_id);
+                generics.fill(&lower_ctx, &mut sm, &src.value);
                 src.file_id
             }
             GenericDefId::TraitId(it) => {
                 let src = it.lookup(db).source(db);
+                let lower_ctx = LowerCtx::new(db, src.file_id);
 
                 // traits get the Self type as an implicit first type parameter
                 let self_param_id = generics.types.alloc(TypeParamData {
@@ -120,14 +127,16 @@ impl GenericParams {
                 // add super traits as bounds on Self
                 // i.e., trait Foo: Bar is equivalent to trait Foo where Self: Bar
                 let self_param = TypeRef::Path(name![Self].into());
-                generics.fill_bounds(&src.value, self_param);
+                generics.fill_bounds(&lower_ctx, &src.value, self_param);
 
-                generics.fill(&mut sm, &src.value);
+                generics.fill(&lower_ctx, &mut sm, &src.value);
                 src.file_id
             }
             GenericDefId::TypeAliasId(it) => {
                 let src = it.lookup(db).source(db);
-                generics.fill(&mut sm, &src.value);
+                let lower_ctx = LowerCtx::new(db, src.file_id);
+
+                generics.fill(&lower_ctx, &mut sm, &src.value);
                 src.file_id
             }
             // Note that we don't add `Self` here: in `impl`s, `Self` is not a
@@ -135,7 +144,9 @@ impl GenericParams {
             // type, so this is handled by the resolver.
             GenericDefId::ImplId(it) => {
                 let src = it.lookup(db).source(db);
-                generics.fill(&mut sm, &src.value);
+                let lower_ctx = LowerCtx::new(db, src.file_id);
+
+                generics.fill(&lower_ctx, &mut sm, &src.value);
                 src.file_id
             }
             // We won't be using this ID anyway
@@ -145,28 +156,38 @@ impl GenericParams {
         (generics, InFile::new(file_id, sm))
     }
 
-    fn fill(&mut self, sm: &mut SourceMap, node: &dyn TypeParamsOwner) {
+    fn fill(&mut self, lower_ctx: &LowerCtx, sm: &mut SourceMap, node: &dyn TypeParamsOwner) {
         if let Some(params) = node.type_param_list() {
-            self.fill_params(sm, params)
+            self.fill_params(lower_ctx, sm, params)
         }
         if let Some(where_clause) = node.where_clause() {
-            self.fill_where_predicates(where_clause);
+            self.fill_where_predicates(lower_ctx, where_clause);
         }
     }
 
-    fn fill_bounds(&mut self, node: &dyn ast::TypeBoundsOwner, type_ref: TypeRef) {
+    fn fill_bounds(
+        &mut self,
+        lower_ctx: &LowerCtx,
+        node: &dyn ast::TypeBoundsOwner,
+        type_ref: TypeRef,
+    ) {
         for bound in
             node.type_bound_list().iter().flat_map(|type_bound_list| type_bound_list.bounds())
         {
-            self.add_where_predicate_from_bound(bound, type_ref.clone());
+            self.add_where_predicate_from_bound(lower_ctx, bound, type_ref.clone());
         }
     }
 
-    fn fill_params(&mut self, sm: &mut SourceMap, params: ast::TypeParamList) {
+    fn fill_params(
+        &mut self,
+        lower_ctx: &LowerCtx,
+        sm: &mut SourceMap,
+        params: ast::TypeParamList,
+    ) {
         for type_param in params.type_params() {
             let name = type_param.name().map_or_else(Name::missing, |it| it.as_name());
             // FIXME: Use `Path::from_src`
-            let default = type_param.default_type().map(TypeRef::from_ast);
+            let default = type_param.default_type().map(|it| TypeRef::from_ast(lower_ctx, it));
             let param = TypeParamData {
                 name: Some(name.clone()),
                 default,
@@ -176,29 +197,34 @@ impl GenericParams {
             sm.insert(param_id, Either::Right(type_param.clone()));
 
             let type_ref = TypeRef::Path(name.into());
-            self.fill_bounds(&type_param, type_ref);
+            self.fill_bounds(&lower_ctx, &type_param, type_ref);
         }
     }
 
-    fn fill_where_predicates(&mut self, where_clause: ast::WhereClause) {
+    fn fill_where_predicates(&mut self, lower_ctx: &LowerCtx, where_clause: ast::WhereClause) {
         for pred in where_clause.predicates() {
             let type_ref = match pred.type_ref() {
                 Some(type_ref) => type_ref,
                 None => continue,
             };
-            let type_ref = TypeRef::from_ast(type_ref);
+            let type_ref = TypeRef::from_ast(lower_ctx, type_ref);
             for bound in pred.type_bound_list().iter().flat_map(|l| l.bounds()) {
-                self.add_where_predicate_from_bound(bound, type_ref.clone());
+                self.add_where_predicate_from_bound(lower_ctx, bound, type_ref.clone());
             }
         }
     }
 
-    fn add_where_predicate_from_bound(&mut self, bound: ast::TypeBound, type_ref: TypeRef) {
+    fn add_where_predicate_from_bound(
+        &mut self,
+        lower_ctx: &LowerCtx,
+        bound: ast::TypeBound,
+        type_ref: TypeRef,
+    ) {
         if bound.question_token().is_some() {
             // FIXME: remove this bound
             return;
         }
-        let bound = TypeBound::from_ast(bound);
+        let bound = TypeBound::from_ast(lower_ctx, bound);
         self.where_predicates
             .push(WherePredicate { target: WherePredicateTarget::TypeRef(type_ref), bound });
     }
diff --git a/crates/ra_hir_def/src/nameres/collector.rs b/crates/ra_hir_def/src/nameres/collector.rs
index 98c74fe25..bf3968bd6 100644
--- a/crates/ra_hir_def/src/nameres/collector.rs
+++ b/crates/ra_hir_def/src/nameres/collector.rs
@@ -204,6 +204,7 @@ impl DefCollector<'_> {
                 ast_id: None,
                 krate: Some(krate),
                 kind: MacroDefKind::CustomDerive(expander),
+                local_inner: false,
             };
 
             self.define_proc_macro(name.clone(), macro_id);
@@ -941,6 +942,7 @@ impl ModCollector<'_, '_> {
                     ast_id: Some(ast_id.ast_id),
                     krate: Some(self.def_collector.def_map.krate),
                     kind: MacroDefKind::Declarative,
+                    local_inner: mac.local_inner,
                 };
                 self.def_collector.define_macro(self.module_id, name.clone(), macro_id, mac.export);
             }
diff --git a/crates/ra_hir_def/src/nameres/raw.rs b/crates/ra_hir_def/src/nameres/raw.rs
index 39b011ad7..a71503c76 100644
--- a/crates/ra_hir_def/src/nameres/raw.rs
+++ b/crates/ra_hir_def/src/nameres/raw.rs
@@ -188,6 +188,7 @@ pub(super) struct MacroData {
     pub(super) path: ModPath,
     pub(super) name: Option<Name>,
     pub(super) export: bool,
+    pub(super) local_inner: bool,
     pub(super) builtin: bool,
 }
 
@@ -401,14 +402,32 @@ impl RawItemsCollector {