44 files changed, 606 insertions, 261 deletions

diff --git a/Cargo.lock b/Cargo.lock
index fd04ec3c5..1aa0c072d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -26,9 +26,9 @@ dependencies = [
 
 [[package]]
 name = "anyhow"
-version = "1.0.36"
+version = "1.0.37"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "68803225a7b13e47191bab76f2687382b60d259e8cf37f6e1893658b84bb9479"
+checksum = "ee67c11feeac938fae061b232e38e0b6d94f97a9df10e6271319325ac4c56a86"
 
 [[package]]
 name = "anymap"
@@ -53,7 +53,7 @@ dependencies = [
  "either",
  "hir",
  "ide_db",
- "itertools",
+ "itertools 0.10.0",
  "profile",
  "rustc-hash",
  "stdx",
@@ -211,7 +211,7 @@ dependencies = [
  "chalk-derive",
  "chalk-ir",
  "ena",
- "itertools",
+ "itertools 0.9.0",
  "petgraph",
  "rustc-hash",
  "tracing",
@@ -250,7 +250,7 @@ dependencies = [
  "expect-test",
  "hir",
  "ide_db",
- "itertools",
+ "itertools 0.10.0",
  "log",
  "profile",
  "rustc-hash",
@@ -349,6 +349,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "524cbf6897b527295dff137cec09ecf3a05f4fddffd7dfcd1585403449e74198"
 
 [[package]]
+name = "dissimilar"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fc4b29f4b9bb94bf267d57269fd0706d343a160937108e9619fe380645428abb"
+
+[[package]]
 name = "drop_bomb"
 version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -534,7 +540,7 @@ dependencies = [
  "hir_def",
  "hir_expand",
  "hir_ty",
- "itertools",
+ "itertools 0.10.0",
  "log",
  "profile",
  "rustc-hash",
@@ -557,7 +563,7 @@ dependencies = [
  "fst",
  "hir_expand",
  "indexmap",
- "itertools",
+ "itertools 0.10.0",
  "log",
  "mbe",
  "once_cell",
@@ -601,7 +607,7 @@ dependencies = [
  "expect-test",
  "hir_def",
  "hir_expand",
- "itertools",
+ "itertools 0.10.0",
  "log",
  "once_cell",
  "profile",
@@ -637,7 +643,7 @@ dependencies = [
  "hir",
  "ide_db",
  "indexmap",
- "itertools",
+ "itertools 0.10.0",
  "log",
  "oorandom",
  "profile",
@@ -661,7 +667,7 @@ dependencies = [
  "expect-test",
  "fst",
  "hir",
- "itertools",
+ "itertools 0.10.0",
  "log",
  "once_cell",
  "profile",
@@ -742,10 +748,19 @@ dependencies = [
 ]
 
 [[package]]
+name = "itertools"
+version = "0.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "37d572918e350e82412fe766d24b15e6682fb2ed2bbe018280caa810397cb319"
+dependencies = [
+ "either",
+]
+
+[[package]]
 name = "itoa"
-version = "0.4.6"
+version = "0.4.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dc6f3ad7b9d11a0c00842ff8de1b60ee58661048eb8049ed33c73594f359d7e6"
+checksum = "dd25036021b0de88a0aff6b850051563c6516d0bf53f8638938edbb9de732736"
 
 [[package]]
 name = "jod-thread"
@@ -1219,7 +1234,7 @@ dependencies = [
  "base_db",
  "cargo_metadata",
  "cfg",
- "itertools",
+ "itertools 0.10.0",
  "log",
  "paths",
  "proc_macro_api",
@@ -1334,6 +1349,7 @@ dependencies = [
  "anyhow",
  "cfg",
  "crossbeam-channel 0.5.0",
+ "dissimilar",
  "env_logger",
  "expect-test",
  "flycheck",
@@ -1342,7 +1358,7 @@ dependencies = [
  "hir_ty",
  "ide",
  "ide_db",
- "itertools",
+ "itertools 0.10.0",
  "jod-thread",
  "log",
  "lsp-server",
@@ -1518,9 +1534,9 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.60"
+version = "1.0.61"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1500e84d27fe482ed1dc791a56eddc2f230046a040fa908c08bda1d9fb615779"
+checksum = "4fceb2595057b6891a4ee808f70054bd2d12f0e97f1cbb78689b59f676df325a"
 dependencies = [
  "indexmap",
  "itoa",
@@ -1586,7 +1602,7 @@ dependencies = [
  "expect-test",
  "hir",
  "ide_db",
- "itertools",
+ "itertools 0.10.0",
  "rustc-hash",
  "syntax",
  "test_utils",
@@ -1599,9 +1615,9 @@ version = "0.0.0"
 
 [[package]]
 name = "syn"
-version = "1.0.55"
+version = "1.0.56"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a571a711dddd09019ccc628e1b17fe87c59b09d513c06c026877aa708334f37a"
+checksum = "a9802ddde94170d186eeee5005b798d9c159fa970403f1be19976d0cfb939b72"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -1627,7 +1643,7 @@ dependencies = [
  "arrayvec",
  "expect-test",
  "indexmap",
- "itertools",
+ "itertools 0.10.0",
  "once_cell",
  "parser",
  "profile",
diff --git a/crates/assists/Cargo.toml b/crates/assists/Cargo.toml
index 3fd8327d6..ed8ad666f 100644
--- a/crates/assists/Cargo.toml
+++ b/crates/assists/Cargo.toml
@@ -11,7 +11,7 @@ doctest = false
 
 [dependencies]
 rustc-hash = "1.1.0"
-itertools = "0.9.0"
+itertools = "0.10.0"
 either = "1.6.1"
 
 stdx = { path = "../stdx", version = "0.0.0" }
diff --git a/crates/assists/src/handlers/extract_variable.rs b/crates/assists/src/handlers/extract_variable.rs
index d2ae137cd..9957012fe 100644
--- a/crates/assists/src/handlers/extract_variable.rs
+++ b/crates/assists/src/handlers/extract_variable.rs
@@ -91,7 +91,7 @@ pub(crate) fn extract_variable(acc: &mut Assists, ctx: &AssistContext) -> Option
             // extra newlines in the indent block
             let text = indent.text();
             if text.starts_with('\n') {
-                buf.push_str("\n");
+                buf.push('\n');
                 buf.push_str(text.trim_start_matches('\n'));
             } else {
                 buf.push_str(text);
diff --git a/crates/assists/src/handlers/replace_derive_with_manual_impl.rs b/crates/assists/src/handlers/replace_derive_with_manual_impl.rs
index 4d6a1956b..cb7a5c104 100644
--- a/crates/assists/src/handlers/replace_derive_with_manual_impl.rs
+++ b/crates/assists/src/handlers/replace_derive_with_manual_impl.rs
@@ -62,21 +62,22 @@ pub(crate) fn replace_derive_with_manual_impl(
     let current_module = ctx.sema.scope(annotated_name.syntax()).module()?;
     let current_crate = current_module.krate();
 
-    let found_traits =
-        imports_locator::find_exact_imports(&ctx.sema, current_crate, trait_token.text())
-            .filter_map(
-                |candidate: either::Either<hir::ModuleDef, hir::MacroDef>| match candidate {
-                    either::Either::Left(hir::ModuleDef::Trait(trait_)) => Some(trait_),
-                    _ => None,
-                },
-            )
-            .flat_map(|trait_| {
-                current_module
-                    .find_use_path(ctx.sema.db, hir::ModuleDef::Trait(trait_))
-                    .as_ref()
-                    .map(mod_path_to_ast)
-                    .zip(Some(trait_))
-            });
+    let found_traits = imports_locator::find_exact_imports(
+        &ctx.sema,
+        current_crate,
+        trait_token.text().to_string(),
+    )
+    .filter_map(|candidate: either::Either<hir::ModuleDef, hir::MacroDef>| match candidate {
+        either::Either::Left(hir::ModuleDef::Trait(trait_)) => Some(trait_),
+        _ => None,
+    })
+    .flat_map(|trait_| {
+        current_module
+            .find_use_path(ctx.sema.db, hir::ModuleDef::Trait(trait_))
+            .as_ref()
+            .map(mod_path_to_ast)
+            .zip(Some(trait_))
+    });
 
     let mut no_traits_found = true;
     for (trait_path, trait_) in found_traits.inspect(|_| no_traits_found = false) {
diff --git a/crates/assists/src/utils/import_assets.rs b/crates/assists/src/utils/import_assets.rs
index ff5c0e78e..4ce82c1ba 100644
--- a/crates/assists/src/utils/import_assets.rs
+++ b/crates/assists/src/utils/import_assets.rs
@@ -179,25 +179,24 @@ impl ImportAssets {
             }
         };
 
-        let mut res =
-            imports_locator::find_exact_imports(sema, current_crate, &self.get_search_query())
-                .filter_map(filter)
-                .filter_map(|candidate| {
-                    let item: hir::ItemInNs = candidate.either(Into::into, Into::into);
-                    if let Some(prefix_kind) = prefixed {
-                        self.module_with_name_to_import.find_use_path_prefixed(
-                            db,
-                            item,
-                            prefix_kind,
-                        )
-                    } else {
-                        self.module_with_name_to_import.find_use_path(db, item)
-                    }
-                    .map(|path| (path, item))
-                })
-                .filter(|(use_path, _)| use_path.len() > 1)
-                .take(20)
-                .collect::<Vec<_>>();
+        let mut res = imports_locator::find_exact_imports(
+            sema,
+            current_crate,
+            self.get_search_query().to_string(),
+        )
+        .filter_map(filter)
+        .filter_map(|candidate| {
+            let item: hir::ItemInNs = candidate.either(Into::into, Into::into);
+            if let Some(prefix_kind) = prefixed {
+                self.module_with_name_to_import.find_use_path_prefixed(db, item, prefix_kind)
+            } else {
+                self.module_with_name_to_import.find_use_path(db, item)
+            }
+            .map(|path| (path, item))
+        })
+        .filter(|(use_path, _)| use_path.len() > 1)
+        .take(20)
+        .collect::<Vec<_>>();
         res.sort_by_key(|(path, _)| path.clone());
         res
     }
diff --git a/crates/completion/Cargo.toml b/crates/completion/Cargo.toml
index 35e169a28..78e93e78e 100644
--- a/crates/completion/Cargo.toml
+++ b/crates/completion/Cargo.toml
@@ -10,7 +10,7 @@ edition = "2018"
 doctest = false
 
 [dependencies]
-itertools = "0.9.0"
+itertools = "0.10.0"
 log = "0.4.8"
 rustc-hash = "1.1.0"
 either = "1.6.1"
diff --git a/crates/completion/src/completions/attribute.rs b/crates/completion/src/completions/attribute.rs
index 19ce2482f..8695eed39 100644
--- a/crates/completion/src/completions/attribute.rs
+++ b/crates/completion/src/completions/attribute.rs
@@ -234,7 +234,7 @@ fn parse_comma_sep_input(derive_input: ast::TokenTree) -> Result<FxHashSet<Strin
                         current_derive = String::new();
                     }
                 } else {
-                    current_derive.push_str(token.to_string().trim());
+                    current_derive.push_str(token.text().trim());
                 }
             }
 
diff --git a/crates/completion/src/completions/postfix.rs b/crates/completion/src/completions/postfix.rs
index d6db82a93..3883d6d21 100644
--- a/crates/completion/src/completions/postfix.rs
+++ b/crates/completion/src/completions/postfix.rs
@@ -502,7 +502,7 @@ fn main() {
     #[test]
     fn postfix_completion_for_format_like_strings() {
         check_edit(
-            "fmt",
+            "format",
             r#"fn main() { "{some_var:?}".<|> }"#,
             r#"fn main() { format!("{:?}", some_var) }"#,
         );
diff --git a/crates/completion/src/completions/postfix/format_like.rs b/crates/completion/src/completions/postfix/format_like.rs
index 88ba86acb..def4b13fb 100644
--- a/crates/completion/src/completions/postfix/format_like.rs
+++ b/crates/completion/src/completions/postfix/format_like.rs
@@ -22,7 +22,7 @@ use syntax::ast::{self, AstToken};
 
 /// Mapping ("postfix completion item" => "macro to use")
 static KINDS: &[(&str, &str)] = &[
-    ("fmt", "format!"),
+    ("format", "format!"),
     ("panic", "panic!"),
     ("println", "println!"),
     ("eprintln", "eprintln!"),
@@ -108,7 +108,8 @@ impl FormatStrParser {
         // "{MyStruct { val_a: 0, val_b: 1 }}".
         let mut inexpr_open_count = 0;
 
-        for chr in self.input.chars() {
+        let mut chars = self.input.chars().peekable();
+        while let Some(chr) = chars.next() {
             match (self.state, chr) {
                 (State::NotExpr, '{') => {
                     self.output.push(chr);
@@ -157,6 +158,11 @@ impl FormatStrParser {
                         inexpr_open_count -= 1;
                     }
                 }
+                (State::Expr, ':') if chars.peek().copied() == Some(':') => {
+                    // path seperator
+                    current_expr.push_str("::");
+                    chars.next();
+                }
                 (State::Expr, ':') => {
                     if inexpr_open_count == 0 {
                         // We're outside of braces, thus assume that it's a specifier, like "{Some(value):?}"
@@ -249,6 +255,9 @@ mod tests {
                 expect![["{:?}; SomeStruct { val_a: 0, val_b: 1 }"]],
             ),
             ("{     2 + 2        }", expect![["{}; 2 + 2"]]),
+            ("{strsim::jaro_winkle(a)}", expect![["{}; strsim::jaro_winkle(a)"]]),
+            ("{foo::bar::baz()}", expect![["{}; foo::bar::baz()"]]),
+            ("{foo::bar():?}", expect![["{:?}; foo::bar()"]]),
         ];
 
         for (input, output) in test_vector {
diff --git a/crates/completion/src/completions/unqualified_path.rs b/crates/completion/src/completions/unqualified_path.rs
index d09849752..81a6d00e2 100644
--- a/crates/completion/src/completions/unqualified_path.rs
+++ b/crates/completion/src/completions/unqualified_path.rs
@@ -101,8 +101,9 @@ fn complete_enum_variants(acc: &mut Completions, ctx: &CompletionContext, ty: &T
 //
 // .Fuzzy search details
 //
-// To avoid an excessive amount of the results returned, completion input is checked for inclusion in the identifiers only
-// (i.e. in `HashMap` in the `std::collections::HashMap` path), also not in the module indentifiers.
+// To avoid an excessive amount of the results returned, completion input is checked for inclusion in the names only
+// (i.e. in `HashMap` in the `std::collections::HashMap` path).
+// For the same reasons, avoids searching for any imports for inputs with their length less that 2 symbols.
 //
 // .Merge Behavior
 //
@@ -126,15 +127,20 @@ fn fuzzy_completion(acc: &mut Completions, ctx: &CompletionContext) -> Option<()
     let _p = profile::span("fuzzy_completion");
     let potential_import_name = ctx.token.to_string();
 
+    if potential_import_name.len() < 2 {
+        return None;
+    }
+
     let current_module = ctx.scope.module()?;
     let anchor = ctx.name_ref_syntax.as_ref()?;
     let import_scope = ImportScope::find_insert_use_container(anchor.syntax(), &ctx.sema)?;
 
+    let user_input_lowercased = potential_import_name.to_lowercase();
     let mut all_mod_paths = imports_locator::find_similar_imports(
         &ctx.sema,
         ctx.krate?,
-        Some(100),
-        &potential_import_name,
+        Some(40),
+        potential_import_name,
         true,
     )
     .filter_map(|import_candidate| {
@@ -150,7 +156,6 @@ fn fuzzy_completion(acc: &mut Completions, ctx: &CompletionContext) -> Option<()
     .filter(|(mod_path, _)| mod_path.len() > 1)
     .collect::<Vec<_>>();
 
-    let user_input_lowercased = potential_import_name.to_lowercase();
     all_mod_paths.sort_by_cached_key(|(mod_path, _)| {
         compute_fuzzy_completion_order_key(mod_path, &user_input_lowercased)
     });
diff --git a/crates/completion/src/lib.rs b/crates/completion/src/lib.rs
index 8e27bb153..c57d05bbe 100644
--- a/crates/completion/src/lib.rs
+++ b/crates/completion/src/lib.rs
@@ -137,7 +137,7 @@ pub fn resolve_completion_edits(
     config: &CompletionConfig,
     position: FilePosition,
     full_import_path: &str,
-    imported_name: &str,
+    imported_name: String,
 ) -> Option<Vec<TextEdit>> {
     let ctx = CompletionContext::new(db, position, config)?;
     let anchor = ctx.name_ref_syntax.as_ref()?;
diff --git a/crates/hir/Cargo.toml b/crates/hir/Cargo.toml
index 6dc5ad63b..d4ea7327e 100644
--- a/crates/hir/Cargo.toml
+++ b/crates/hir/Cargo.toml
@@ -14,7 +14,7 @@ log = "0.4.8"
 rustc-hash = "1.1.0"
 either = "1.5.3"
 arrayvec = "0.5.1"
-itertools = "0.9.0"
+itertools = "0.10.0"
 
 stdx = { path = "../stdx", version = "0.0.0" }
 syntax = { path = "../syntax", version = "0.0.0" }
diff --git a/crates/hir_def/Cargo.toml b/crates/hir_def/Cargo.toml
index a88b5f57e..e8b581e2f 100644
--- a/crates/hir_def/Cargo.toml
+++ b/crates/hir_def/Cargo.toml
@@ -17,7 +17,7 @@ either = "1.5.3"
 anymap = "0.12.1"
 drop_bomb = "0.1.4"
 fst = { version = "0.4", default-features = false }
-itertools = "0.9.0"
+itertools = "0.10.0"
 indexmap = "1.4.0"
 smallvec = "1.4.0"
 
diff --git a/crates/hir_def/src/import_map.rs b/crates/hir_def/src/import_map.rs
index c0f108848..30b22f51d 100644
--- a/crates/hir_def/src/import_map.rs
+++ b/crates/hir_def/src/import_map.rs
@@ -238,32 +238,53 @@ pub enum ImportKind {
     BuiltinType,
 }
 
+/// A way to match import map contents against the search query.
+#[derive(Debug)]
+pub enum SearchMode {
+    /// Import map entry should strictly match the query string.
+    Equals,
+    /// Import map entry should contain the query string.
+    Contains,
+    /// Import map entry should contain all letters from the query string,
+    /// in the same order, but not necessary adjacent.
+    Fuzzy,
+}
+
 #[derive(Debug)]
 pub struct Query {
     query: String,
     lowercased: String,
-    anchor_end: bool,
+    name_only: bool,
+    search_mode: SearchMode,
     case_sensitive: bool,
     limit: usize,
     exclude_import_kinds: FxHashSet<ImportKind>,
 }
 
 impl Query {
-    pub fn new(query: &str) -> Self {
+    pub fn new(query: String) -> Self {
+        let lowercased = query.to_lowercase();
         Self {
-            lowercased: query.to_lowercase(),
-            query: query.to_string(),
-            anchor_end: false,
+            query,
+            lowercased,
+            name_only: false,
+            search_mode: SearchMode::Contains,
             case_sensitive: false,
             limit: usize::max_value(),
             exclude_import_kinds: FxHashSet::default(),
         }
     }
 
-    /// Only returns items whose paths end with the (case-insensitive) query string as their last
-    /// segment.
-    pub fn anchor_end(self) -> Self {
-        Self { anchor_end: true, ..self }
+    /// Matches entries' names only, ignoring the rest of
+    /// the qualifier.
+    /// Example: for `std::marker::PhantomData`, the name is `PhantomData`.
+    pub fn name_only(self) -> Self {
+        Self { name_only: true, ..self }
+    }
+
+    /// Specifies the way to search for the entries using the query.
+    pub fn search_mode(self, search_mode: SearchMode) -> Self {
+        Self { search_mode, ..self }
     }
 
     /// Limits the returned number of items to `limit`.
@@ -283,6 +304,40 @@ impl Query {
     }
 }
 
+fn contains_query(query: &Query, input_path: &ImportPath, enforce_lowercase: bool) -> bool {
+    let mut input = if query.name_only {
+        input_path.segments.last().unwrap().to_string()
+    } else {
+        input_path.to_string()
+    };
+    if enforce_lowercase || !query.case_sensitive {
+        input.make_ascii_lowercase();
+    }
+
+    let query_string =
+        if !enforce_lowercase && query.case_sensitive { &query.query } else { &query.lowercased };
+
+    match query.search_mode {
+        SearchMode::Equals => &input == query_string,
+        SearchMode::Contains => input.contains(query_string),
+        SearchMode::Fuzzy => {
+            let mut unchecked_query_chars = query_string.chars();
+            let mut mismatching_query_char = unchecked_query_chars.next();
+
+            for input_char in input.chars() {
+                match mismatching_query_char {
+                    None => return true,
+                    Some(matching_query_char) if matching_query_char == input_char => {
+                        mismatching_query_char = unchecked_query_chars.next();
+                    }
+                    _ => (),
+                }
+            }
+            mismatching_query_char.is_none()
+        }
+    }
+}
+
 /// Searches dependencies of `krate` for an importable path matching `query`.
 ///
 /// This returns a list of items that could be imported from dependencies of `krate`.
@@ -312,39 +367,29 @@ pub fn search_dependencies<'a>(
             let importables = &import_map.importables[indexed_value.value as usize..];
 
             // Path shared by the importable items in this group.
-            let path = &import_map.map[&importables[0]].path;
-
-            if query.anchor_end {
-                // Last segment must match query.
-                let last = path.segments.last().unwrap().to_string();
-                if last.to_lowercase() != query.lowercased {
-                    continue;
-                }
+            let common_importables_path = &import_map.map[&importables[0]].path;
+            if !contains_query(&query, common_importables_path, true) {
+                continue;
             }
 
+            let common_importables_path_fst = fst_path(common_importables_path);
             // Add the items from this `ModPath` group. Those are all subsequent items in
             // `importables` whose paths match `path`.
             let iter = importables
                 .iter()
                 .copied()
                 .take_while(|item| {
-                    let item_path = &import_map.map[item].path;
-                    fst_path(item_path) == fst_path(path)
+                    common_importables_path_fst == fst_path(&import_map.map[item].path)
                 })
                 .filter(|&item| match item_import_kind(item) {
                     Some(import_kind) => !query.exclude_import_kinds.contains(&import_kind),
                     None => true,
+                })
+                .filter(|item| {
+                    !query.case_sensitive // we've already checked the common importables path case-insensitively
+                        || contains_query(&query, &import_map.map[item].path, false)
                 });
-
-            if query.case_sensitive {
-                // FIXME: This does not do a subsequence match.
-                res.extend(iter.filter(|item| {
-                    let item_path = &import_map.map[item].path;
-                    item_path.to_string().contains(&query.query)
-                }));
-            } else {
-                res.extend(iter);
-            }
+            res.extend(iter);
 
             if res.len() >= query.limit {
                 res.truncate(query.limit);
@@ -387,8 +432,9 @@ fn item_import_kind(item: ItemInNs) -> Option<ImportKind> {
 mod tests {
     use base_db::{fixture::WithFixture, SourceDatabase, Upcast};
     use expect_test::{expect, Expect};
+    use stdx::format_to;
 
-    use crate::{test_db::TestDB, AssocContainerId, Lookup};
+    use crate::{data::FunctionData, test_db::TestDB, AssocContainerId, Lookup};
 
     use super::*;
 
@@ -407,14 +453,32 @@ mod tests {
             .into_iter()
             .filter_map(|item| {
                 let mark = match item {
+                    ItemInNs::Types(ModuleDefId::FunctionId(_))
+                    | ItemInNs::Values(ModuleDefId::FunctionId(_)) => "f",
                     ItemInNs::Types(_) => "t",
                     ItemInNs::Values(_) => "v",
                     ItemInNs::Macros(_) => "m",
                 };
-                let item = assoc_to_trait(&db, item);
                 item.krate(db.upcast()).map(|krate| {
                     let map = db.import_map(krate);
-                    let path = map.path_of(item).unwrap();
+
+                    let path = match assoc_to_trait(&db, item) {
+                        Some(trait_) => {
+                            let mut full_path = map.path_of(trait_).unwrap().to_string();
+                            if let ItemInNs::Types(ModuleDefId::FunctionId(function_id))
+                            | ItemInNs::Values(ModuleDefId::FunctionId(function_id)) = item
+                            {
+                                format_to!(
+                                    full_path,
+                                    "::{}",
+                                    FunctionData::fn_data_query(&db, function_id).name,
+                                );
+                            }
+                            full_path
+                        }
+                        None => map.path_of(item).unwrap().to_string(),
+                    };
+
                     format!(
                         "{}::{} ({})\n",
                         crate_graph[krate].display_name.as_ref().unwrap(),
@@ -427,15 +491,15 @@ mod tests {
         expect.assert_eq(&actual)
     }
 
-    fn assoc_to_trait(db: &dyn DefDatabase, item: ItemInNs) -> ItemInNs {
+    fn assoc_to_trait(db: &dyn DefDatabase, item: ItemInNs) -> Option<ItemInNs> {
         let assoc: AssocItemId = match item {
             ItemInNs::Types(it) | ItemInNs::Values(it) => match it {
                 ModuleDefId::TypeAliasId(it) => it.into(),
                 ModuleDefId::FunctionId(it) => it.into(),
                 ModuleDefId::ConstId(it) => it.into(),
-                _ => return item,
+                _ => return None,
             },
-            _ => return item,
+            _ => return None,
         };
 
         let container = match assoc {
@@ -445,8 +509,8 @@ mod tests {
         };
 
         match container {
-            AssocContainerId::TraitId(it) => ItemInNs::Types(it.into()),
-            _ => item,
+            AssocContainerId::TraitId(it) => Some(ItemInNs::Types(it.into())),
+            _ => None,
         }
     }
 
@@ -685,7 +749,7 @@ mod tests {
     }
 
     #[test]
-    fn search() {
+    fn search_mode() {
         let ra_fixture = r#"
             //- /main.rs crate:main deps:dep
             //- /dep.rs crate:dep deps:tdep
@@ -713,28 +777,96 @@ mod tests {
         check_search(
             ra_fixture,
             "main",
-            Query::new("fmt"),
+            Query::new("fmt".to_string()).search_mode(SearchMode::Fuzzy),
             expect![[r#"
                 dep::fmt (t)
                 dep::Fmt (t)
                 dep::Fmt (v)
                 dep::Fmt (m)
                 dep::fmt::Display (t)
-                dep::format (v)
+                dep::format (f)
+                dep::fmt::Display::fmt (f)
+            "#]],
+        );
+
+        check_search(
+            ra_fixture,
+            "main",
+            Query::new("fmt".to_string()).search_mode(SearchMode::Equals),
+            expect![[r#"
+                dep::fmt (t)
+                dep::Fmt (t)
+                dep::Fmt (v)
+                dep::Fmt (m)
+                dep::fmt::Display::fmt (f)
+            "#]],
+        );
+
+        check_search(
+            ra_fixture,
+            "main",
+            Query::new("fmt".to_string()).search_mode(SearchMode::Contains),
+            expect![[r#"
+                dep::fmt (t)
+                dep::Fmt (t)
+                dep::Fmt (v)
+                dep::Fmt (m)
                 dep::fmt::Display (t)
+                dep::fmt::Display::fmt (f)
             "#]],
         );
+    }
+
+    #[test]
+    fn name_only() {
+        let ra_fixture = r#"
+            //- /main.rs crate:main deps:dep
+            //- /dep.rs crate:dep deps:tdep
+            use tdep::fmt as fmt_dep;
+            pub mod fmt {
+                pub trait Display {
+                    fn fmt();
+                }
+            }
+            #[macro_export]
+            macro_rules! Fmt {
+                () => {};
+            }
+            pub struct Fmt;
+
+            pub fn format() {}
+            pub fn no() {}
+
+            //- /tdep.rs crate:tdep
+            pub mod fmt {
+                pub struct NotImportableFromMain;
+            }
+        "#;
 
         check_search(
             ra_fixture,
             "main",
-            Query::new("fmt").anchor_end(),
+            Query::new("fmt".to_string()),
             expect![[r#"
                 dep::fmt (t)
                 dep::Fmt (t)
                 dep::Fmt (v)
                 dep::Fmt (m)
                 dep::fmt::Display (t)
+                dep::fmt::Display::fmt (f)
+            "#]],
+        );
+
+        check_search(
+            ra_fixture,
+            "main",
+            Query::new("fmt".to_string()).name_only(),
+            expect![[r#"
+                dep::fmt (t)
+                dep::Fmt (t)
+                dep::Fmt (v)
+                dep::Fmt (m)
+                dep::fmt::Display::fmt (f)
             "#]],
         );
     }
@@ -752,7 +884,7 @@ mod tests {
         check_search(
             ra_fixture,
             "main",
-            Query::new("FMT"),
+            Query::new("FMT".to_string()),
             expect![[r#"
                 dep::fmt (t)
                 dep::fmt (v)
@@ -764,7 +896,7 @@ mod tests {
         check_search(
             ra_fixture,
             "main",
-            Query::new("FMT").case_sensitive(),
+            Query::new("FMT".to_string()).case_sensitive(),
             expect![[r#"
                 dep::FMT (t)
                 dep::FMT (v)
@@ -793,7 +925,7 @@ mod tests {
         pub fn no() {}
     "#,
             "main",
-            Query::new("").limit(2),
+            Query::new("".to_string()).limit(2),
             expect![[r#"
                 dep::fmt (t)
                 dep::Fmt (t)
@@ -814,7 +946,7 @@ mod tests {
         check_search(
             ra_fixture,
             "main",
-            Query::new("FMT"),
+            Query::new("FMT".to_string()),
             expect![[r#"
                 dep::fmt (t)
                 dep::fmt (v)
@@ -826,7 +958,7 @@ mod tests {
         check_search(
             ra_fixture,
             "main",
-            Query::new("FMT").exclude_import_kind(ImportKind::Adt),
+            Query::new("FMT".to_string()).exclude_import_kind(ImportKind::Adt),
             expect![[r#""#]],
         );
     }
diff --git a/crates/hir_def/src/nameres.rs b/crates/hir_def/src/nameres.rs
index ffd0381d4..5682e122d 100644
--- a/crates/hir_def/src/nameres.rs
+++ b/crates/hir_def/src/nameres.rs
@@ -249,7 +249,7 @@ impl CrateDefMap {
                     buf.push_str(" _");
                 }
 
-                buf.push_str("\n");
+                buf.push('\n');
             }
 
             for (name, child) in map.modules[module].children.iter() {
@@ -454,7 +454,7 @@ mod diagnostics {
                                     });
                                 for token in tokens {
                                     if token.kind() == SyntaxKind::IDENT
-                                        && token.to_string() == *name
+                                        && token.text() == name.as_str()
                                     {
                                         precise_location = Some(token.text_range());
                                         break 'outer;
diff --git a/crates/hir_expand/src/builtin_macro.rs b/crates/hir_expand/src/builtin_macro.rs
index 6382521fb..80b60d59f 100644
--- a/crates/hir_expand/src/builtin_macro.rs
+++ b/crates/hir_expand/src/builtin_macro.rs
@@ -259,7 +259,8 @@ fn format_args_expand(
     }
     for arg in &mut args {
         // Remove `key =`.
-        if matches!(arg.get(1), Some(tt::TokenTree::Leaf(tt::Leaf::Punct(p))) if p.char == '=') {
+        if matches!(arg.get(1), Some(tt::TokenTree::Leaf(tt::Leaf::Punct(p))) if p.char == '=' && p.spacing != tt::Spacing::Joint)
+        {
             arg.drain(..2);
         }
     }
diff --git a/crates/hir_ty/Cargo.toml b/crates/hir_ty/Cargo.toml
index 965c1780a..2dfccd191 100644
--- a/crates/hir_ty/Cargo.toml
+++ b/crates/hir_ty/Cargo.toml
@@ -10,7 +10,7 @@ edition = "2018"
 doctest = false
 
 [dependencies]
-itertools = "0.9.0"
+itertools = "0.10.0"
 arrayvec = "0.5.1"
 smallvec = "1.2.0"
 ena = "0.14.0"
diff --git a/crates/hir_ty/src/infer/expr.rs b/crates/hir_ty/src/infer/expr.rs
index 70a3f3075..f2fc69b2f 100644
--- a/crates/hir_ty/src/infer/expr.rs
+++ b/crates/hir_ty/src/infer/expr.rs
@@ -648,6 +648,8 @@ impl<'a> InferenceContext<'a> {
             }
             Expr::Array(array) => {
                 let elem_ty = match &expected.ty {
+                    // FIXME: remove when https://github.com/rust-lang/rust/issues/80501 is fixed
+                    #[allow(unreachable_patterns)]
                     ty_app!(TypeCtor::Array, st) | ty_app!(TypeCtor::Slice, st) => {
                         st.as_single().clone()
                     }
diff --git a/crates/ide/Cargo.toml b/crates/ide/Cargo.toml
index 4d483580d..f1544dbe0 100644
--- a/crates/ide/Cargo.toml
+++ b/crates/ide/Cargo.toml
@@ -12,7 +12,7 @@ doctest = false
 [dependencies]
 either = "1.5.3"
 indexmap = "1.4.0"
-itertools = "0.9.0"
+itertools = "0.10.0"
 log = "0.4.8"
 rustc-hash = "1.1.0"
 oorandom = "11.1.2"
diff --git a/crates/ide/src/diagnostics.rs b/crates/ide/src/diagnostics.rs
index 038273750..79d126ff2 100644
--- a/crates/ide/src/diagnostics.rs
+++ b/crates/ide/src/diagnostics.rs
@@ -199,6 +199,12 @@ fn check_unnecessary_braces_in_use_statement(
 ) -> Option<()> {
     let use_tree_list = ast::UseTreeList::cast(node.clone())?;
     if let Some((single_use_tree,)) = use_tree_list.use_trees().collect_tuple() {
+        // If there is a comment inside the bracketed `use`,
+        // assume it is a commented out module path and don't show diagnostic.
+        if use_tree_list.has_inner_comment() {
+            return Some(());
+        }
+
         let use_range = use_tree_list.syntax().text_range();
         let edit =
             text_edit_for_remove_unnecessary_braces_with_self_in_use_statement(&single_use_tree)
@@ -638,6 +644,22 @@ mod a {
 }
 "#,
         );
+        check_no_diagnostics(
+            r#"
+use a;
+use a::{
+    c,
+    // d::e
+};
+
+mod a {
+    mod c {}
+    mod d {
+        mod e {}
+    }
+}
+"#,
+        );
         check_fix(
             r"
             mod b {}
diff --git a/crates/ide/src/lib.rs b/crates/ide/src/lib.rs
index 41eb139d1..b3331f03f 100644
--- a/crates/ide/src/lib.rs
+++ b/crates/ide/src/lib.rs
@@ -475,7 +475,7 @@ impl Analysis {
         config: &CompletionConfig,
         position: FilePosition,
         full_import_path: &str,
-        imported_name: &str,
+        imported_name: String,
     ) -> Cancelable<Vec<TextEdit>> {
         Ok(self
             .with_db(|db| {
diff --git a/crates/ide_db/Cargo.toml b/crates/ide_db/Cargo.toml
index 0ad6e1000..ebe53c8ee 100644
--- a/crates/ide_db/Cargo.toml
+++ b/crates/ide_db/Cargo.toml
@@ -19,7 +19,7 @@ fst = { version = "0.4", default-features = false }
 rustc-hash = "1.1.0"
 once_cell = "1.3.1"
 either = "1.6.1"
-itertools = "0.9.0"
+itertools = "0.10.0"
 
 stdx = { path = "../stdx", version = "0.0.0" }
 syntax = { path = "../syntax", version = "0.0.0" }
diff --git a/crates/ide_db/src/imports_locator.rs b/crates/ide_db/src/imports_locator.rs
index b2980a5d6..0f4c2ca47 100644
--- a/crates/ide_db/src/imports_locator.rs
+++ b/crates/ide_db/src/imports_locator.rs
@@ -15,19 +15,23 @@ use rustc_hash::FxHashSet;
 pub fn find_exact_imports<'a>(
     sema: &Semantics<'a, RootDatabase>,
     krate: Crate,
-    name_to_import: &str,
+    name_to_import: String,
 ) -> impl Iterator<Item = Either<ModuleDef, MacroDef>> {
     let _p = profile::span("find_exact_imports");
     find_imports(
         sema,
         krate,
         {
-            let mut local_query = symbol_index::Query::new(name_to_import.to_string());
+            let mut local_query = symbol_index::Query::new(name_to_import.clone());
             local_query.exact();
             local_query.limit(40);
             local_query
         },
-        import_map::Query::new(name_to_import).anchor_end().case_sensitive().limit(40),
+        import_map::Query::new(name_to_import)
+            .limit(40)
+            .name_only()
+            .search_mode(import_map::SearchMode::Equals)
+            .case_sensitive(),
     )
 }
 
@@ -35,17 +39,18 @@ pub fn find_similar_imports<'a>(
     sema: &Semantics<'a, RootDatabase>,
     krate: Crate,
     limit: Option<usize>,
-    name_to_import: &str,
-    ignore_modules: bool,
+    fuzzy_search_string: String,
+    name_only: bool,
 ) -> impl Iterator<Item = Either<ModuleDef, MacroDef>> {
     let _p = profile::span("find_similar_imports");
 
-    let mut external_query = import_map::Query::new(name_to_import);
-    if ignore_modules {
-        external_query = external_query.exclude_import_kind(import_map::ImportKind::Module);
+    let mut external_query = import_map::Query::new(fuzzy_search_string.clone())
+        .search_mode(import_map::SearchMode::Fuzzy);
+    if name_only {
+        external_query = external_query.name_only();
     }
 
-    let mut local_query = symbol_index::Query::new(name_to_import.to_string());
+    let mut local_query = symbol_index::Query::new(fuzzy_search_string);
 
     if let Some(limit) = limit {
         local_query.limit(limit);
diff --git a/crates/mbe/src/lib.rs b/crates/mbe/src/lib.rs
index 3ad609a00..b3472879d 100644
--- a/crates/mbe/src/lib.rs
+++ b/crates/mbe/src/lib.rs
@@ -14,10 +14,10 @@ mod tests;
 
 use std::fmt;
 
-pub use tt::{Delimiter, Punct};
+pub use tt::{Delimiter, DelimiterKind, Punct};
 
 use crate::{
-    parser::{parse_pattern, Op},
+    parser::{parse_pattern, parse_template, Op},
     tt_iter::TtIter,
 };
 
@@ -78,8 +78,24 @@ pub struct MacroRules {
 
 #[derive(Clone, Debug, PartialEq, Eq)]
 struct Rule {
-    lhs: tt::Subtree,
-    rhs: tt::Subtree,
+    lhs: MetaTemplate,
+    rhs: MetaTemplate,
+}
+
+#[derive(Clone, Debug, PartialEq, Eq)]
+struct MetaTemplate {
+    delimiter: Option<Delimiter>,
+    tokens: Vec<Result<Op, ExpandError>>,
+}
+
+impl<'a> MetaTemplate {
+    fn iter(&self) -> impl Iterator<Item = &Result<Op, ExpandError>> {
+        self.tokens.iter()
+    }
+
+    fn delimiter_kind(&self) -> Option<DelimiterKind> {
+        self.delimiter.map(|it| it.kind)
+    }
 }
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
@@ -167,7 +183,7 @@ impl MacroRules {
             rules.push(rule);
             if let Err(()) = src.expect_char(';') {
                 if src.len() > 0 {
-                    return Err(ParseError::Expected("expected `:`".to_string()));
+                    return Err(ParseError::Expected("expected `;`".to_string()));
                 }
                 break;
             }
@@ -201,23 +217,23 @@ impl MacroRules {
 
 impl Rule {
     fn parse(src: &mut TtIter) -> Result<Rule, ParseError> {
-        let mut lhs = src
+        let lhs = src
             .expect_subtree()
-            .map_err(|()| ParseError::Expected("expected subtree".to_string()))?
-            .clone();
-        lhs.delimiter = None;
+            .map_err(|()| ParseError::Expected("expected subtree".to_string()))?;
         src.expect_char('=').map_err(|()| ParseError::Expected("expected `=`".to_string()))?;
         src.expect_char('>').map_err(|()| ParseError::Expected("expected `>`".to_string()))?;
-        let mut rhs = src
+        let rhs = src
             .expect_subtree()
-            .map_err(|()| ParseError::Expected("expected subtree".to_string()))?
-            .clone();
-        rhs.delimiter = None;
+            .map_err(|()| ParseError::Expected("expected subtree".to_string()))?;
+
+        let lhs = MetaTemplate { tokens: parse_pattern(&lhs), delimiter: None };
+        let rhs = MetaTemplate { tokens: parse_template(&rhs), delimiter: None };
+
         Ok(crate::Rule { lhs, rhs })
     }
 }
 
-fn to_parse_error(e: ExpandError) -> ParseError {
+fn to_parse_error(e: &ExpandError) -> ParseError {
     let msg = match e {
         ExpandError::InvalidRepeat => "invalid repeat".to_string(),
         _ => "invalid macro definition".to_string(),
@@ -225,22 +241,22 @@ fn to_parse_error(e: ExpandError) -> ParseError {
     ParseError::Expected(msg)
 }
 
-fn validate(pattern: &tt::Subtree) -> Result<(), ParseError> {
-    for op in parse_pattern(pattern) {
-        let op = op.map_err(to_parse_error)?;
+fn validate(pattern: &MetaTemplate) -> Result<(), ParseError> {
+    for op in pattern.iter() {
+        let op = op.as_ref().map_err(|e| to_parse_error(&e))?;
 
         match op {
-            Op::TokenTree(tt::TokenTree::Subtree(subtree)) => validate(subtree)?,
+            Op::Subtree(subtree) => validate(&subtree)?,
             Op::Repeat { subtree, separator, .. } => {
                 // Checks that no repetition which could match an empty token
                 // https://github.com/rust-lang/rust/blob/a58b1ed44f5e06976de2bdc4d7dc81c36a96934f/src/librustc_expand/mbe/macro_rules.rs#L558
 
                 if separator.is_none() {
-                    if parse_pattern(subtree).all(|child_op| {
-                        match child_op.map_err(to_parse_error) {
+                    if subtree.iter().all(|child_op| {
+                        match child_op.as_ref().map_err(to_parse_error) {
                             Ok(Op::Var { kind, .. }) => {
                                 // vis is optional
-                                if kind.map_or(false, |it| it == "vis") {
+                                if kind.as_ref().map_or(false, |it| it == "vis") {
                                     return true;
                                 }
                             }
diff --git a/crates/mbe/src/mbe_expander/matcher.rs b/crates/mbe/src/mbe_expander/matcher.rs
index 44722c0f1..ab5f87c48 100644
--- a/crates/mbe/src/mbe_expander/matcher.rs
+++ b/crates/mbe/src/mbe_expander/matcher.rs
@@ -2,10 +2,10 @@
 
 use crate::{
     mbe_expander::{Binding, Bindings, Fragment},
-    parser::{parse_pattern, Op, RepeatKind, Separator},
+    parser::{Op, RepeatKind, Separator},
     subtree_source::SubtreeTokenSource,
     tt_iter::TtIter,
-    ExpandError,
+    ExpandError, MetaTemplate,
 };
 
 use super::ExpandResult;
@@ -83,7 +83,7 @@ impl Match {
 // sense to try using it. Matching errors are added to the `Match`. It might
 // make sense to make pattern parsing a separate step?
 
-pub(super) fn match_(pattern: &tt::Subtree, src: &tt::Subtree) -> Result<Match, ExpandError> {
+pub(super) fn match_(pattern: &MetaTemplate, src: &tt::Subtree) -> Result<Match, ExpandError> {
     assert!(pattern.delimiter == None);
 
     let mut res = Match::default();
@@ -101,12 +101,12 @@ pub(super) fn match_(pattern: &tt::Subtree, src: &tt::Subtree) -> Result<Match,
 
 fn match_subtree(
     res: &mut Match,
-    pattern: &tt::Subtree,
+    pattern: &MetaTemplate,
     src: &mut TtIter,
 ) -> Result<(), ExpandError> {
-    for op in parse_pattern(pattern) {
-        match op? {
-            Op::TokenTree(tt::TokenTree::Leaf(lhs)) => {
+    for op in pattern.iter() {
+        match op.as_ref().map_err(|err| err.clone())? {
+            Op::Leaf(lhs) => {
                 let rhs = match src.expect_leaf() {
                     Ok(l) => l,
                     Err(()) => {
@@ -132,7 +132,7 @@ fn match_subtree(
                     }
                 }
             }
-            Op::TokenTree(tt::TokenTree::Subtree(lhs)) => {
+            Op::Subtree(lhs) => {
                 let rhs = match src.expect_subtree() {
                     Ok(s) => s,
                     Err(()) => {
@@ -172,7 +172,7 @@ fn match_subtree(
                 }
             }
             Op::Repeat { subtree, kind, separator } => {
-                match_repeat(res, subtree, kind, separator, src)?;
+                match_repeat(res, subtree, *kind, separator, src)?;
             }
         }
     }
@@ -372,9 +372,9 @@ impl<'a> TtIter<'a> {
 
 pub(super) fn match_repeat(
     res: &mut Match,
-    pattern: &tt::Subtree,
+    pattern: &MetaTemplate,
     kind: RepeatKind,
-    separator: Option<Separator>,
+    separator: &Option<Separator>,
     src: &mut TtIter,
 ) -> Result<(), ExpandError> {
     // Dirty hack to make macro-expansion terminate.
@@ -489,12 +489,12 @@ fn match_meta_var(kind: &str, input: &mut TtIter) -> ExpandResult<Option<Fragmen
     result.map(|tt| if kind == "expr" { tt.map(Fragment::Ast) } else { tt.map(Fragment::Tokens) })
 }
 
-fn collect_vars(buf: &mut Vec<SmolStr>, pattern: &tt::Subtree) -> Result<(), ExpandError> {
-    for op in parse_pattern(pattern) {
-        match op? {
+fn collect_vars(buf: &mut Vec<SmolStr>, pattern: &MetaTemplate) -> Result<(), ExpandError> {
+    for op in pattern.iter() {
+        match op.as_ref().map_err(|e| e.clone())? {
             Op::Var { name, .. } => buf.push(name.clone()),
-            Op::TokenTree(tt::TokenTree::Leaf(_)) => (),
-            Op::TokenTree(tt::TokenTree::Subtree(subtree)) => collect_vars(buf, subtree)?,
+            Op::Leaf(_) => (),
+            Op::Subtree(subtree) => collect_vars(buf, subtree)?,
             Op::Repeat { subtree, .. } => collect_vars(buf, subtree)?,
         }
     }
diff --git a/crates/mbe/src/mbe_expander/transcriber.rs b/crates/mbe/src/mbe_expander/transcriber.rs
index 57592dc92..720531237 100644
--- a/crates/mbe/src/mbe_expander/transcriber.rs
+++ b/crates/mbe/src/mbe_expander/transcriber.rs
@@ -6,8 +6,8 @@ use syntax::SmolStr;
 use super::ExpandResult;
 use crate::{
     mbe_expander::{Binding, Bindings, Fragment},
-    parser::{parse_template, Op, RepeatKind, Separator},
-    ExpandError,
+    parser::{Op, RepeatKind, Separator},
+    ExpandError, MetaTemplate,
 };
 
 impl Bindings {
@@ -50,7 +50,10 @@ impl Bindings {
     }
 }
 
-pub(super) fn transcribe(template: &tt::Subtree, bindings: &Bindings) -> ExpandResult<tt::Subtree> {
+pub(super) fn transcribe(
+    template: &MetaTemplate,
+    bindings: &Bindings,
+) -> ExpandResult<tt::Subtree> {
     assert!(template.delimiter == None);
     let mut ctx = ExpandCtx { bindings: &bindings, nesting: Vec::new() };
     let mut arena: Vec<tt::TokenTree> = Vec::new();
@@ -76,35 +79,35 @@ struct ExpandCtx<'a> {
 
 fn expand_subtree(
     ctx: &mut ExpandCtx,
-    template: &tt::Subtree,
+    template: &MetaTemplate,
     arena: &mut Vec<tt::TokenTree>,
 ) -> ExpandResult<tt::Subtree> {
     // remember how many elements are in the arena now - when returning, we want to drain exactly how many elements we added. This way, the recursive uses of the arena get their own "view" of the arena, but will reuse the allocation
     let start_elements = arena.len();
     let mut err = None;
-    for op in parse_template(template) {
+    for op in template.iter() {
         let op = match op {
             Ok(op) => op,
             Err(e) => {
-                err = Some(e);
+                err = Some(e.clone());
                 break;
             }
         };
         match op {
-            Op::TokenTree(tt @ tt::TokenTree::Leaf(..)) => arena.push(tt.clone()),
-            Op::TokenTree(tt::TokenTree::Subtree(tt)) => {
-                let ExpandResult { value: tt, err: e } = expand_subtree(ctx, tt, arena);
+            Op::Leaf(tt) => arena.push(tt.clone().into()),
+            Op::Subtree(tt) => {
+                let ExpandResult { value: tt, err: e } = expand_subtree(ctx, &tt, arena);
                 err = err.or(e);
                 arena.push(tt.into());
             }
             Op::Var { name, .. } => {
-                let ExpandResult { value: fragment, err: e } = expand_var(ctx, name);
+                let ExpandResult { value: fragment, err: e } = expand_var(ctx, &name);
                 err = err.or(e);
                 push_fragment(arena, fragment);
             }
             Op::Repeat { subtree, kind, separator } => {
                 let ExpandResult { value: fragment, err: e } =
-                    expand_repeat(ctx, subtree, kind, separator, arena);
+                    expand_repeat(ctx, subtree, *kind, separator, arena);
                 err = err.or(e);
                 push_fragment(arena, fragment)
             }
@@ -161,9 +164,9 @@ fn expand_var(ctx: &mut ExpandCtx, v: &SmolStr) -> ExpandResult<Fragment> {
 
 fn expand_repeat(
     ctx: &mut ExpandCtx,
-    template: &tt::Subtree,
+    template: &MetaTemplate,
     kind: RepeatKind,
-    separator: Option<Separator>,
+    separator: &Option<Separator>,
     arena: &mut Vec<tt::TokenTree>,
 ) -> ExpandResult<Fragment> {
     let mut buf: Vec<tt::TokenTree> = Vec::new();
diff --git a/crates/mbe/src/parser.rs b/crates/mbe/src/parser.rs
index d681905f5..2f3ebc831 100644
--- a/crates/mbe/src/parser.rs
+++ b/crates/mbe/src/parser.rs
@@ -4,16 +4,17 @@
 use smallvec::SmallVec;
 use syntax::SmolStr;
 
-use crate::{tt_iter::TtIter, ExpandError};
+use crate::{tt_iter::TtIter, ExpandError, MetaTemplate};
 
-#[derive(Debug)]
-pub(crate) enum Op<'a> {
-    Var { name: &'a SmolStr, kind: Option<&'a SmolStr> },
-    Repeat { subtree: &'a tt::Subtree, kind: RepeatKind, separator: Option<Separator> },
-    TokenTree(&'a tt::TokenTree),
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub(crate) enum Op {
+    Var { name: SmolStr, kind: Option<SmolStr> },
+    Repeat { subtree: MetaTemplate, kind: RepeatKind, separator: Option<Separator> },
+    Leaf(tt::Leaf),
+    Subtree(MetaTemplate),
 }
 
-#[derive(Clone, Debug, PartialEq, Eq)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub(crate) enum RepeatKind {
     ZeroOrMore,
     OneOrMore,
@@ -45,16 +46,12 @@ impl PartialEq for Separator {
     }
 }
 
-pub(crate) fn parse_template(
-    template: &tt::Subtree,
-) -> impl Iterator<Item = Result<Op<'_>, ExpandError>> {
-    parse_inner(template, Mode::Template)
+pub(crate) fn parse_template(template: &tt::Subtree) -> Vec<Result<Op, ExpandError>> {
+    parse_inner(&template, Mode::Template)
 }
 
-pub(crate) fn parse_pattern(
-    pattern: &tt::Subtree,
-) -> impl Iterator<Item = Result<Op<'_>, ExpandError>> {
-    parse_inner(pattern, Mode::Pattern)
+pub(crate) fn parse_pattern(pattern: &tt::Subtree) -> Vec<Result<Op, ExpandError>> {
+    parse_inner(&pattern, Mode::Pattern)
 }
 
 #[derive(Clone, Copy)]
@@ -63,12 +60,13 @@ enum Mode {
     Template,
 }
 
-fn parse_inner(src: &tt::Subtree, mode: Mode) -> impl Iterator<Item = Result<Op<'_>, ExpandError>> {
-    let mut src = TtIter::new(src);
+fn parse_inner(tt: &tt::Subtree, mode: Mode) -> Vec<Result<Op, ExpandError>> {
+    let mut src = TtIter::new(&tt);
     std::iter::from_fn(move || {
         let first = src.next()?;
         Some(next_op(first, &mut src, mode))
     })
+    .collect()
 }
 
 macro_rules! err {
@@ -83,21 +81,20 @@ macro_rules! bail {
     };
 }
 
-fn next_op<'a>(
-    first: &'a tt::TokenTree,
-    src: &mut TtIter<'a>,
-    mode: Mode,
-) -> Result<Op<'a>, ExpandError> {
+fn next_op<'a>(first: &tt::TokenTree, src: &mut TtIter<'a>, mode: Mode) -> Result<Op, ExpandError> {
     let res = match first {
-        tt::TokenTree::Leaf(tt::Leaf::Punct(tt::Punct { char: '$', .. })) => {
+        tt::TokenTree::Leaf(leaf @ tt::Leaf::Punct(tt::Punct { char: '$', .. })) => {
             // Note that the '$' itself is a valid token inside macro_rules.
             let second = match src.next() {
-                None => return Ok(Op::TokenTree(first)),
+                None => return Ok(Op::Leaf(leaf.clone())),
                 Some(it) => it,
             };
             match second {
                 tt::TokenTree::Subtree(subtree) => {
                     let (separator, kind) = parse_repeat(src)?;
+                    let delimiter = subtree.delimiter;
+                    let tokens = parse_inner(&subtree, mode);
+                    let subtree = MetaTemplate { tokens, delimiter };
                     Op::Repeat { subtree, separator, kind }
                 }
                 tt::TokenTree::Leaf(leaf) => match leaf {
@@ -107,18 +104,18 @@ fn next_op<'a>(
                         if punct.char != '_' {
                             return Err(ExpandError::UnexpectedToken);
                         }
-                        let name = &UNDERSCORE;
+                        let name = UNDERSCORE.clone();
                         let kind = eat_fragment_kind(src, mode)?;
                         Op::Var { name, kind }
                     }
                     tt::Leaf::Ident(ident) => {
-                        let name = &ident.text;
+                        let name = ident.text.clone();
                         let kind = eat_fragment_kind(src, mode)?;
                         Op::Var { name, kind }
                     }
                     tt::Leaf::Literal(lit) => {
-                        if is_boolean_literal(lit) {
-                            let name = &lit.text;
+                        if is_boolean_literal(&lit) {
+                            let name = lit.text.clone();
                             let kind = eat_fragment_kind(src, mode)?;
                             Op::Var { name, kind }
                         } else {
@@ -128,19 +125,22 @@ fn next_op<'a>(
                 },
             }
         }
-        tt => Op::TokenTree(tt),
+        tt::TokenTree::Leaf(tt) => Op::Leaf(tt.clone()),
+        tt::TokenTree::Subtree(subtree) => {
+            let delimiter = subtree.delimiter;
+            let tokens = parse_inner(&subtree, mode);
+            let subtree = MetaTemplate { tokens, delimiter };
+            Op::Subtree(subtree)
+        }
     };
     Ok(res)
 }
 
-fn eat_fragment_kind<'a>(
-    src: &mut TtIter<'a>,
-    mode: Mode,
-) -> Result<Option<&'a SmolStr>, ExpandError> {
+fn eat_fragment_kind<'a>(src: &mut TtIter<'a>, mode: Mode) -> Result<Option<SmolStr>, ExpandError> {
     if let Mode::Pattern = mode {
         src.expect_char(':').map_err(|()| err!("bad fragment specifier 1"))?;
         let ident = src.expect_ident().map_err(|()| err!("bad fragment specifier 1"))?;
-        return Ok(Some(&ident.text));
+        return Ok(Some(ident.text.clone()));
     };
     Ok(None)
 }
diff --git a/crates/proc_macro_srv/src/rustc_server.rs b/crates/proc_macro_srv/src/rustc_server.rs
index 503f4c101..b54aa1f3b 100644
--- a/crates/proc_macro_srv/src/rustc_server.rs
+++ b/crates/proc_macro_srv/src/rustc_server.rs
@@ -204,17 +204,18 @@ pub mod token_stream {
                 let content = subtree
                     .token_trees
                     .iter()
-                    .map(|tkn| {
-                        let s = to_text(tkn);
+                    .fold((String::new(), true), |(last, last_to_joint), tkn| {
+                        let s = [last, to_text(tkn)].join(if last_to_joint { "" } else { " " });
+                        let mut is_joint = false;
                         if let tt::TokenTree::Leaf(tt::Leaf::Punct(punct)) = tkn {
-                            if punct.spacing == tt::Spacing::Alone {
-                                return s + " ";
+                            if punct.spacing == tt::Spacing::Joint {
+                                is_joint = true;
                             }
                         }
-                        s
+                        (s, is_joint)
                     })
-                    .collect::<Vec<_>>()
-                    .concat();
+                    .0;
+
                 let (open, close) = match subtree.delimiter.map(|it| it.kind) {
                     None => ("", ""),
                     Some(tt::DelimiterKind::Brace) => ("{", "}"),
@@ -710,4 +711,32 @@ mod tests {
         assert_eq!(srv.character('c').text, "'c'");
         assert_eq!(srv.byte_string(b"1234586\x88").text, "b\"1234586\\x88\"");
     }
+
+    #[test]
+    fn test_rustc_server_to_string() {
+        let s = TokenStream {
+            subtree: tt::Subtree {
+                delimiter: None,
+                token_trees: vec![
+                    tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
+                        text: "struct".into(),
+                        id: tt::TokenId::unspecified(),
+                    })),
+                    tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
+                        text: "T".into(),
+                        id: tt::TokenId::unspecified(),
+                    })),
+                    tt::TokenTree::Subtree(tt::Subtree {
+                        delimiter: Some(tt::Delimiter {
+                            id: tt::TokenId::unspecified(),
+                            kind: tt::DelimiterKind::Brace,
+                        }),
+                        token_trees: vec![],
+                    }),
+                ],
+            },
+        };
+
+        assert_eq!(s.to_string(), "struct T {}");
+    }
 }
diff --git a/crates/project_model/Cargo.toml b/crates/project_model/Cargo.toml
index c55e85709..a65e42261 100644
--- a/crates/project_model/Cargo.toml
+++ b/crates/project_model/Cargo.toml
@@ -16,7 +16,7 @@ cargo_metadata = "=0.12.0"
 serde = { version = "1.0.106", features = ["derive"] }
 serde_json = "1.0.48"
 anyhow = "1.0.26"
-itertools = "0.9.0"
+itertools = "0.10.0"
 
 arena = { path = "../arena", version = "0.0.0" }
 cfg = { path = "../cfg", version = "0.0.0" }
diff --git a/crates/project_model/src/cargo_workspace.rs b/crates/project_model/src/cargo_workspace.rs
index 3e0b40cbc..1700cb8a7 100644
--- a/crates/project_model/src/cargo_workspace.rs
+++ b/crates/project_model/src/cargo_workspace.rs
@@ -1,6 +1,7 @@
 //! FIXME: write short doc here
 
 use std::{
+    convert::TryInto,
     ffi::OsStr,
     ops,
     path::{Path, PathBuf},
@@ -196,8 +197,23 @@ impl CargoWorkspace {
         if let Some(target) = target {
             meta.other_options(vec![String::from("--filter-platform"), target]);
         }
+
         let mut meta = meta.exec().with_context(|| {
-            format!("Failed to run `cargo metadata --manifest-path {}`", cargo_toml.display())
+            let cwd: Option<AbsPathBuf> =
+                std::env::current_dir().ok().and_then(|p| p.try_into().ok());
+
+            let workdir = cargo_toml
+                .parent()
+                .map(|p| p.to_path_buf())
+                .or(cwd)
+                .map(|dir| dir.to_string_lossy().to_string())
+                .unwrap_or_else(|| "<failed to get path>".into());
+
+            format!(
+                "Failed to run `cargo metadata --manifest-path {}` in `{}`",
+                cargo_toml.display(),
+                workdir
+            )
         })?;
 
         let mut out_dir_by_id = FxHashMap::default();
diff --git a/crates/rust-analyzer/Cargo.toml b/crates/rust-analyzer/Cargo.toml
index 53e70eaf7..0a63593fb 100644
--- a/crates/rust-analyzer/Cargo.toml
+++ b/crates/rust-analyzer/Cargo.toml
@@ -17,8 +17,9 @@ path = "src/bin/main.rs"
 [dependencies]
 anyhow = "1.0.26"
 crossbeam-channel = "0.5.0"
+dissimilar = "1.0.2"
 env_logger = { version = "0.8.1", default-features = false }
-itertools = "0.9.0"
+itertools = "0.10.0"
 jod-thread = "0.1.0"
 log = "0.4.8"
 lsp-types = { version = "0.86.0", features = ["proposed"] }
diff --git a/crates/rust-analyzer/src/diff.rs b/crates/rust-analyzer/src/diff.rs
new file mode 100644
index 000000000..231be5807
--- /dev/null
+++ b/crates/rust-analyzer/src/diff.rs
@@ -0,0 +1,53 @@
+//! Generate minimal `TextEdit`s from different text versions
+use dissimilar::Chunk;
+use ide::{TextEdit, TextRange, TextSize};
+
+pub(crate) fn diff(left: &str, right: &str) -> TextEdit {
+    let chunks = dissimilar::diff(left, right);
+    textedit_from_chunks(chunks)
+}
+
+fn textedit_from_chunks(chunks: Vec<dissimilar::Chunk>) -> TextEdit {
+    let mut builder = TextEdit::builder();
+    let mut pos = TextSize::default();
+
+    let mut chunks = chunks.into_iter().peekable();
+    while let Some(chunk) = chunks.next() {
+        if let (Chunk::Delete(deleted), Some(&Chunk::Insert(inserted))) = (chunk, chunks.peek()) {
+            chunks.next().unwrap();
+            let deleted_len = TextSize::of(deleted);
+            builder.replace(TextRange::at(pos, deleted_len), inserted.into());
+            pos += deleted_len;
+            continue;
+        }
+
+        match chunk {
+            Chunk::Equal(text) => {
+                pos += TextSize::of(text);
+            }
+            Chunk::Delete(deleted) => {
+                let deleted_len = TextSize::of(deleted);
+                builder.delete(TextRange::at(pos, deleted_len));
+                pos += deleted_len;
+            }
+            Chunk::Insert(inserted) => {
+                builder.insert(pos, inserted.into());
+            }
+        }
+    }
+    builder.finish()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn diff_applies() {
+        let mut original = String::from("fn foo(a:u32){\n}");
+        let result = "fn foo(a: u32) {}";
+        let edit = diff(&original, result);
+        edit.apply(&mut original);
+        assert_eq!(original, result);
+    }
+}
diff --git a/crates/rust-analyzer/src/handlers.rs b/crates/rust-analyzer/src/handlers.rs
index 374fb5302..948cfc17c 100644
--- a/crates/rust-analyzer/src/handlers.rs
+++ b/crates/rust-analyzer/src/handlers.rs
@@ -31,6 +31,7 @@ use serde_json::to_value;
 use stdx::{format_to, split_once};
 use syntax::{algo, ast, AstNode, TextRange, TextSize};
 
+use crate::diff::diff;
 use crate::{
     cargo_target_spec::CargoTargetSpec,
     config::RustfmtConfig,
@@ -681,7 +682,7 @@ pub(crate) fn handle_completion_resolve(
             &snap.config.completion,
             FilePosition { file_id, offset },
             &resolve_data.full_import_path,
-            &resolve_data.imported_name,
+            resolve_data.imported_name,
         )?
         .into_iter()
         .flat_map(|edit| {
@@ -840,7 +841,7 @@ pub(crate) fn handle_formatting(
     let crate_ids = snap.analysis.crate_for(file_id)?;
 
     let file_line_index = snap.analysis.file_line_index(file_id)?;
-    let end_position = to_proto::position(&file_line_index, TextSize::of(file.as_str()));
+    let file_line_endings = snap.file_line_endings(file_id);
 
     let mut rustfmt = match &snap.config.rustfmt {
         RustfmtConfig::Rustfmt { extra_args } => {
@@ -861,16 +862,18 @@ pub(crate) fn handle_formatting(
         }
     };
 
-    let mut rustfmt = rustfmt.stdin(Stdio::piped()).stdout(Stdio::piped()).spawn()?;
+    let mut rustfmt =
+        rustfmt.stdin(Stdio::piped()).stdout(Stdio::piped()).stderr(Stdio::piped()).spawn()?;
 
     rustfmt.stdin.as_mut().unwrap().write_all(file.as_bytes())?;
 
     let output = rustfmt.wait_with_output()?;
     let captured_stdout = String::from_utf8(output.stdout)?;
+    let captured_stderr = String::from_utf8(output.stderr).unwrap_or_default();
 
     if !output.status.success() {
         match output.status.code() {
-            Some(1) => {
+            Some(1) if !captured_stderr.contains("not installed") => {
                 // While `rustfmt` doesn't have a specific exit code for parse errors this is the
                 // likely cause exiting with 1. Most Language Servers swallow parse errors on
                 // formatting because otherwise an error is surfaced to the user on top of the
@@ -886,8 +889,9 @@ pub(crate) fn handle_formatting(
                     format!(
                         r#"rustfmt exited with:
                            Status: {}
-                           stdout: {}"#,
-                        output.status, captured_stdout,
+                           stdout: {}
+                           stderr: {}"#,
+                        output.status, captured_stdout, captured_stderr,
                     ),
                 )
                 .into());
@@ -899,10 +903,11 @@ pub(crate) fn handle_formatting(
         // The document is already formatted correctly -- no edits needed.
         Ok(None)
     } else {
-        Ok(Some(vec![lsp_types::TextEdit {
-            range: Range::new(Position::new(0, 0), end_position),
-            new_text: captured_stdout,
-        }]))
+        Ok(Some(to_proto::text_edit_vec(
+            &file_line_index,
+            file_line_endings,
+            diff(&file, &captured_stdout),
+        )))
     }
 }
 
diff --git a/crates/rust-analyzer/src/lib.rs b/crates/rust-analyzer/src/lib.rs
index d538ad69a..c9494e300 100644
--- a/crates/rust-analyzer/src/lib.rs
+++ b/crates/rust-analyzer/src/lib.rs
@@ -34,6 +34,7 @@ mod request_metrics;
 mod lsp_utils;
 mod thread_pool;
 mod document;
+mod diff;
 pub mod lsp_ext;
 pub mod config;
 
diff --git a/crates/rust-analyzer/tests/rust-analyzer/main.rs b/crates/rust-analyzer/tests/rust-analyzer/main.rs
index e51eb2626..84db0856d 100644
--- a/crates/rust-analyzer/tests/rust-analyzer/main.rs
+++ b/crates/rust-analyzer/tests/rust-analyzer/main.rs
@@ -190,15 +190,10 @@ pub use std::collections::HashMap;
         },
         json!([
             {
-                "newText": r#"mod bar;
-
-fn main() {}
-
-pub use std::collections::HashMap;
-"#,
+                "newText": "",
                 "range": {
-                    "end": { "character": 0, "line": 6 },
-                    "start": { "character": 0, "line": 0 }
+                    "end": { "character": 0, "line": 3 },
+                    "start": { "character": 11, "line": 2 }
                 }
             }
         ]),
@@ -248,17 +243,17 @@ pub use std::collections::HashMap;
         },
         json!([
             {
-                "newText": r#"mod bar;
-
-async fn test() {}
-
-fn main() {}
-
-pub use std::collections::HashMap;
-"#,
+                "newText": "",
+                "range": {
+                    "end": { "character": 0, "line": 3 },
+                    "start": { "character": 17, "line": 2 }
+                }
+            },
+            {
+                "newText": "",
                 "range": {
-                    "end": { "character": 0, "line": 9 },
-                    "start": { "character": 0, "line": 0 }
+                    "end": { "character": 0, "line": 6 },
+                    "start": { "character": 11, "line": 5 }
                 }
             }
         ]),
diff --git a/crates/ssr/Cargo.toml b/crates/ssr/Cargo.toml
index 98ed25fb6..339eda86a 100644
--- a/crates/ssr/Cargo.toml
+++ b/crates/ssr/Cargo.toml
@@ -12,7 +12,7 @@ doctest = false
 
 [dependencies]
 rustc-hash = "1.1.0"
-itertools = "0.9.0"
+itertools = "0.10.0"
 
 text_edit = { path = "../text_edit", version = "0.0.0" }
 syntax = { path = "../syntax", version = "0.0.0" }
diff --git a/crates/ssr/src/matching.rs b/crates/ssr/src/matching.rs
index 99b187311..6cf831431 100644
--- a/crates/ssr/src/matching.rs
+++ b/crates/ssr/src/matching.rs
@@ -473,7 +473,9 @@ impl<'db, 'sema> Matcher<'db, 'sema> {
                         }
                         SyntaxElement::Node(n) => {
                             if let Some(first_token) = n.first_token() {
-                                if Some(first_token.to_string()) == next_pattern_token {
+                                if Some(first_token.text().as_str())
+                                    == next_pattern_token.as_deref()
+                                {
                                     if let Some(SyntaxElement::Node(p)) = pattern.next() {
                                         // We have a subtree that starts with the next token in our pattern.
                                         self.attempt_match_token_tree(phase, &p, &n)?;
diff --git a/crates/syntax/Cargo.toml b/crates/syntax/Cargo.toml
index 21015591c..5d8389ade 100644
--- a/crates/syntax/Cargo.toml
+++ b/crates/syntax/Cargo.toml
@@ -11,7 +11,7 @@ edition = "2018"
 doctest = false
 
 [dependencies]
-itertools = "0.9.0"
+itertools = "0.10.0"
 rowan = "0.10.0"
 rustc_lexer = { version = "695.0.0", package = "rustc-ap-rustc_lexer" }
 rustc-hash = "1.1.0"
diff --git a/crates/syntax/src/ast/node_ext.rs b/crates/syntax/src/ast/node_ext.rs
index c45cb514a..2aa472fb4 100644
--- a/crates/syntax/src/ast/node_ext.rs
+++ b/crates/syntax/src/ast/node_ext.rs
@@ -193,6 +193,14 @@ impl ast::UseTreeList {
             .and_then(ast::UseTree::cast)
             .expect("UseTreeLists are always nested in UseTrees")
     }
+
+    pub fn has_inner_comment(&self) -> bool {
+        self.syntax()
+            .children_with_tokens()
+            .filter_map(|it| it.into_token())
+            .find_map(ast::Comment::cast)
+            .is_some()
+    }
 }
 
 impl ast::Impl {
diff --git a/editors/code/package.json b/editors/code/package.json
index 13749a084..587f11b90 100644
--- a/editors/code/package.json
+++ b/editors/code/package.json
@@ -283,6 +283,14 @@
                     "default": null,
                     "markdownDescription": "Path to rust-analyzer executable (points to bundled binary by default). If this is set, then `#rust-analyzer.updates.channel#` setting is not used"
                 },
+                "rust-analyzer.server.extraEnv": {
+                    "type": [
+                        "null",
+                        "object"
+                    ],
+                    "default": null,
+                    "markdownDescription": "Extra environment variables that will be passed to the rust-analyzer executable. Useful for passing e.g. `RA_LOG` for debugging."
+                },
                 "rust-analyzer.trace.server": {
                     "type": "string",
                     "scope": "window",
diff --git a/editors/code/src/client.ts b/editors/code/src/client.ts
index 63ab82dde..539e487ec 100644
--- a/editors/code/src/client.ts
+++ b/editors/code/src/client.ts
@@ -6,6 +6,10 @@ import { DocumentSemanticsTokensSignature, DocumentSemanticsTokensEditsSignature
 import { assert } from './util';
 import { WorkspaceEdit } from 'vscode';
 
+export interface Env {
+    [name: string]: string;
+}
+
 function renderCommand(cmd: ra.CommandLink) {
     return `[${cmd.title}](command:${cmd.command}?${encodeURIComponent(JSON.stringify(cmd.arguments))} '${cmd.tooltip!}')`;
 }
@@ -27,14 +31,17 @@ async function semanticHighlightingWorkaround<R, F extends (...args: any[]) => v
     return res;
 }
 
-export function createClient(serverPath: string, cwd: string): lc.LanguageClient {
+export function createClient(serverPath: string, cwd: string, extraEnv: Env): lc.LanguageClient {
     // '.' Is the fallback if no folder is open
     // TODO?: Workspace folders support Uri's (eg: file://test.txt).
     // It might be a good idea to test if the uri points to a file.
 
+    const newEnv = Object.assign({}, process.env);
+    Object.assign(newEnv, extraEnv);
+
     const run: lc.Executable = {
         command: serverPath,
-        options: { cwd },
+        options: { cwd, env: newEnv },
     };
     const serverOptions: lc.ServerOptions = {
         run,
diff --git a/editors/code/src/commands.ts b/editors/code/src/commands.ts
index 9d4823a34..b12e134ca 100644
--- a/editors/code/src/commands.ts
+++ b/editors/code/src/commands.ts
@@ -469,8 +469,14 @@ export function resolveCodeAction(ctx: Ctx): Cmd {
         if (!item.edit) {
             return;
         }
-        const edit = client.protocol2CodeConverter.asWorkspaceEdit(item.edit);
-        await vscode.workspace.applyEdit(edit);
+        const itemEdit = item.edit;
+        const edit = client.protocol2CodeConverter.asWorkspaceEdit(itemEdit);
+        // filter out all text edits and recreate the WorkspaceEdit without them so we can apply
+        // snippet edits on our own
+        const itemEditWithoutTextEdits = { ...item, documentChanges: itemEdit.documentChanges?.filter(change => "kind" in change) };
+        const editWithoutTextEdits = client.protocol2CodeConverter.asWorkspaceEdit(itemEditWithoutTextEdits);
+        await applySnippetWorkspaceEdit(edit);
+        await vscode.workspace.applyEdit(editWithoutTextEdits);
     };
 }
 
diff --git a/editors/code/src/config.ts b/editors/code/src/config.ts
index 848e92af9..fe9f3b4a8 100644
--- a/editors/code/src/config.ts
+++ b/editors/code/src/config.ts
@@ -1,4 +1,5 @@
 import * as vscode from 'vscode';
+import { Env } from './client';
 import { log } from "./util";
 
 export type UpdatesChannel = "stable" | "nightly";
@@ -13,6 +14,7 @@ export class Config {
     readonly rootSection = "rust-analyzer";
     private readonly requiresReloadOpts = [
         "serverPath",
+        "server",
         "cargo",
         "procMacro",
         "files",
@@ -92,6 +94,7 @@ export class Config {
     }
 
     get serverPath() { return this.get<null | string>("serverPath"); }
+    get serverExtraEnv() { return this.get<Env | null>("server.extraEnv") ?? {}; }
     get channel() { return this.get<UpdatesChannel>("updates.channel"); }
     get askBeforeDownload() { return this.get<boolean>("updates.askBeforeDownload"); }
     get traceExtension() { return this.get<boolean>("trace.extension"); }
diff --git a/editors/code/src/ctx.ts b/editors/code/src/ctx.ts
index d39864d33..e7585184b 100644
--- a/editors/code/src/ctx.ts
+++ b/editors/code/src/ctx.ts
@@ -24,7 +24,7 @@ export class Ctx {
         serverPath: string,
         cwd: string,
     ): Promise<Ctx> {
-        const client = createClient(serverPath, cwd);
+        const client = createClient(serverPath, cwd, config.serverExtraEnv);
 
         const statusBar = vscode.window.createStatusBarItem(vscode.StatusBarAlignment.Left);
         extCtx.subscriptions.push(statusBar);