19 files changed, 553 insertions, 300 deletions

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
new file mode 100644
index 000000000..864373aa5
--- /dev/null
+++ b/crates/ra_assists/src/handlers/add_from_impl_for_enum.rs
@@ -0,0 +1,206 @@
+use ra_syntax::{
+    ast::{self, AstNode, NameOwner},
+    TextUnit,
+};
+use stdx::format_to;
+
+use crate::{Assist, AssistCtx, AssistId};
+use ra_ide_db::RootDatabase;
+
+// Assist add_from_impl_for_enum
+//
+// Adds a From impl for an enum variant with one tuple field
+//
+// ```
+// enum A { <|>One(u32) }
+// ```
+// ->
+// ```
+// enum A { One(u32) }
+//
+// impl From<u32> for A {
+//     fn from(v: u32) -> Self {
+//         A::One(v)
+//     }
+// }
+// ```
+pub(crate) fn add_from_impl_for_enum(ctx: AssistCtx) -> Option<Assist> {
+    let variant = ctx.find_node_at_offset::<ast::EnumVariant>()?;
+    let variant_name = variant.name()?;
+    let enum_name = variant.parent_enum().name()?;
+    let field_list = match variant.kind() {
+        ast::StructKind::Tuple(field_list) => field_list,
+        _ => return None,
+    };
+    if field_list.fields().count() != 1 {
+        return None;
+    }
+    let field_type = field_list.fields().next()?.type_ref()?;
+    let path = match field_type {
+        ast::TypeRef::PathType(p) => p,
+        _ => return None,
+    };
+
+    if already_has_from_impl(ctx.sema, &variant) {
+        return None;
+    }
+
+    ctx.add_assist(
+        AssistId("add_from_impl_for_enum"),
+        "Add From impl for this enum variant",
+        |edit| {
+            let start_offset = variant.parent_enum().syntax().text_range().end();
+            let mut buf = String::new();
+            format_to!(
+                buf,
+                r#"
+
+impl From<{0}> for {1} {{
+    fn from(v: {0}) -> Self {{
+        {1}::{2}(v)
+    }}
+}}"#,
+                path.syntax(),
+                enum_name,
+                variant_name
+            );
+            edit.insert(start_offset, buf);
+            edit.set_cursor(start_offset + TextUnit::of_str("\n\n"));
+        },
+    )
+}
+
+fn already_has_from_impl(
+    sema: &'_ hir::Semantics<'_, RootDatabase>,
+    variant: &ast::EnumVariant,
+) -> bool {
+    let scope = sema.scope(&variant.syntax());
+
+    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 e: hir::Enum = match sema.to_def(&variant.parent_enum()) {
+        Some(e) => e,
+        None => return false,
+    };
+    let e_ty = e.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);
+
+    e_ty.impls_trait(sema.db, from_trait, &[var_ty.clone()])
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::helpers::{check_assist, check_assist_not_applicable};
+
+    #[test]
+    fn test_add_from_impl_for_enum() {
+        check_assist(
+            add_from_impl_for_enum,
+            "enum A { <|>One(u32) }",
+            r#"enum A { One(u32) }
+
+<|>impl From<u32> for A {
+    fn from(v: u32) -> Self {
+        A::One(v)
+    }
+}"#,
+        );
+    }
+
+    #[test]
+    fn test_add_from_impl_for_enum_complicated_path() {
+        check_assist(
+            add_from_impl_for_enum,
+            "enum A { <|>One(foo::bar::baz::Boo) }",
+            r#"enum A { One(foo::bar::baz::Boo) }
+
+<|>impl From<foo::bar::baz::Boo> for A {
+    fn from(v: foo::bar::baz::Boo) -> Self {
+        A::One(v)
+    }
+}"#,
+        );
+    }
+
+    #[test]
+    fn test_add_from_impl_no_element() {
+        check_assist_not_applicable(add_from_impl_for_enum, "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) }");
+    }
+
+    #[test]
+    fn test_add_from_impl_struct_variant() {
+        check_assist_not_applicable(add_from_impl_for_enum, "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), }
+
+impl From<u32> for A {
+    fn from(v: u32) -> Self {
+        A::One(v)
+    }
+}
+
+pub trait From<T> {
+    fn from(T) -> Self;
+}"#,
+        );
+    }
+
+    #[test]
+    fn test_add_from_impl_different_variant_impl_exists() {
+        check_assist(
+            add_from_impl_for_enum,
+            r#"enum A { <|>One(u32), Two(String), }
+
+impl From<String> for A {
+    fn from(v: String) -> Self {
+        A::Two(v)
+    }
+}
+
+pub trait From<T> {
+    fn from(T) -> Self;
+}"#,
+            r#"enum A { One(u32), Two(String), }
+
+<|>impl From<u32> for A {
+    fn from(v: u32) -> Self {
+        A::One(v)
+    }
+}
+
+impl From<String> for A {
+    fn from(v: String) -> Self {
+        A::Two(v)
+    }
+}
+
+pub trait From<T> {
+    fn from(T) -> Self;
+}"#,
+        );
+    }
+}
diff --git a/crates/ra_assists/src/lib.rs b/crates/ra_assists/src/lib.rs
index 66854cb5a..fa3d3913f 100644
--- a/crates/ra_assists/src/lib.rs
+++ b/crates/ra_assists/src/lib.rs
@@ -123,6 +123,7 @@ mod handlers {
     mod replace_qualified_name_with_use;
     mod replace_unwrap_with_match;
     mod split_import;
+    mod add_from_impl_for_enum;
 
     pub(crate) fn all() -> &'static [AssistHandler] {
         &[
@@ -161,6 +162,7 @@ mod handlers {
             replace_qualified_name_with_use::replace_qualified_name_with_use,
             replace_unwrap_with_match::replace_unwrap_with_match,
             split_import::split_import,
+            add_from_impl_for_enum::add_from_impl_for_enum,
         ]
     }
 }
diff --git a/crates/ra_hir/src/code_model.rs b/crates/ra_hir/src/code_model.rs
index cd2a8fc62..c6f3bdb8e 100644
--- a/crates/ra_hir/src/code_model.rs
+++ b/crates/ra_hir/src/code_model.rs
@@ -1084,6 +1084,26 @@ impl Type {
         )
     }
 
+    pub fn impls_trait(&self, db: &dyn HirDatabase, trait_: Trait, args: &[Type]) -> bool {
+        let trait_ref = hir_ty::TraitRef {
+            trait_: trait_.id,
+            substs: Substs::build_for_def(db, trait_.id)
+                .push(self.ty.value.clone())
+                .fill(args.iter().map(|t| t.ty.value.clone()))
+                .build(),
+        };
+
+        let goal = Canonical {
+            value: hir_ty::InEnvironment::new(
+                self.ty.environment.clone(),
+                hir_ty::Obligation::Trait(trait_ref),
+            ),
+            num_vars: 0,
+        };
+
+        db.trait_solve(self.krate, goal).is_some()
+    }
+
     // FIXME: this method is broken, as it doesn't take closures into account.
     pub fn as_callable(&self) -> Option<CallableDef> {
         Some(self.ty.value.as_callable()?.0)
diff --git a/crates/ra_hir_ty/src/infer/pat.rs b/crates/ra_hir_ty/src/infer/pat.rs
index baed6225b..86acd27f8 100644
--- a/crates/ra_hir_ty/src/infer/pat.rs
+++ b/crates/ra_hir_ty/src/infer/pat.rs
@@ -11,7 +11,7 @@ use hir_def::{
 use hir_expand::name::Name;
 use test_utils::tested_by;
 
-use super::{BindingMode, InferenceContext};
+use super::{BindingMode, Expectation, InferenceContext};
 use crate::{utils::variant_data, Substs, Ty, TypeCtor};
 
 impl<'a> InferenceContext<'a> {
@@ -198,7 +198,14 @@ impl<'a> InferenceContext<'a> {
 
                 Ty::apply_one(container_ty, elem_ty)
             }
-            _ => Ty::Unknown,
+            Pat::Wild => expected.clone(),
+            Pat::Range { start, end } => {
+                let start_ty = self.infer_expr(*start, &Expectation::has_type(expected.clone()));
+                let end_ty = self.infer_expr(*end, &Expectation::has_type(start_ty));
+                end_ty
+            }
+            Pat::Lit(expr) => self.infer_expr(*expr, &Expectation::has_type(expected.clone())),
+            Pat::Missing => Ty::Unknown,
         };
         // use a new type variable if we got Ty::Unknown here
         let ty = self.insert_type_vars_shallow(ty);
diff --git a/crates/ra_hir_ty/src/tests/coercion.rs b/crates/ra_hir_ty/src/tests/coercion.rs
index 1e303f5ce..3e3d55c04 100644
--- a/crates/ra_hir_ty/src/tests/coercion.rs
+++ b/crates/ra_hir_ty/src/tests/coercion.rs
@@ -275,12 +275,14 @@ fn test(i: i32) {
     [70; 147) 'match ...     }': &[i32]
     [76; 77) 'i': i32
     [88; 89) '2': i32
+    [88; 89) '2': i32
     [93; 96) 'foo': fn foo<i32>(&[i32]) -> &[i32]
     [93; 102) 'foo(&[2])': &[i32]
     [97; 101) '&[2]': &[i32; _]
     [98; 101) '[2]': [i32; _]
     [99; 100) '2': i32
     [112; 113) '1': i32
+    [112; 113) '1': i32
     [117; 121) '&[1]': &[i32; _]
     [118; 121) '[1]': [i32; _]
     [119; 120) '1': i32
@@ -316,10 +318,12 @@ fn test(i: i32) {
     [70; 147) 'match ...     }': &[i32]
     [76; 77) 'i': i32
     [88; 89) '1': i32
+    [88; 89) '1': i32
     [93; 97) '&[1]': &[i32; _]
     [94; 97) '[1]': [i32; _]
     [95; 96) '1': i32
     [107; 108) '2': i32
+    [107; 108) '2': i32
     [112; 115) 'foo': fn foo<i32>(&[i32]) -> &[i32]
     [112; 121) 'foo(&[2])': &[i32]
     [116; 120) '&[2]': &[i32; _]
@@ -357,9 +361,11 @@ fn test() {
     [45; 142) 'match ...     }': *const i32
     [51; 52) '1': i32
     [63; 64) '1': i32
+    [63; 64) '1': i32
     [68; 69) 't': &mut i32
     [68; 81) 't as *mut i32': *mut i32
     [91; 92) '2': i32
+    [91; 92) '2': i32
     [96; 97) 't': &mut i32
     [96; 105) 't as &i32': &i32
     [115; 116) '_': i32
diff --git a/crates/ra_hir_ty/src/tests/patterns.rs b/crates/ra_hir_ty/src/tests/patterns.rs
index 76aa32024..6e5d2247c 100644
--- a/crates/ra_hir_ty/src/tests/patterns.rs
+++ b/crates/ra_hir_ty/src/tests/patterns.rs
@@ -82,6 +82,90 @@ fn test(x: &i32) {
 }
 
 #[test]
+fn infer_literal_pattern() {
+    assert_snapshot!(
+        infer_with_mismatches(r#"
+fn any<T>() -> T { loop {} }
+fn test(x: &i32) {
+    if let "foo" = any() {}
+    if let 1 = any() {}
+    if let 1u32 = any() {}
+    if let 1f32 = any() {}
+    if let 1.0 = any() {}
+    if let true = any() {}
+}
+"#, true),
+        @r###"
+    [18; 29) '{ loop {} }': T
+    [20; 27) 'loop {}': !
+    [25; 27) '{}': ()
+    [38; 39) 'x': &i32
+    [47; 209) '{     ...) {} }': ()
+    [53; 76) 'if let...y() {}': ()
+    [60; 65) '"foo"': &str
+    [60; 65) '"foo"': &str
+    [68; 71) 'any': fn any<&str>() -> &str
+    [68; 73) 'any()': &str
+    [74; 76) '{}': ()
+    [81; 100) 'if let...y() {}': ()
+    [88; 89) '1': i32
+    [88; 89) '1': i32
+    [92; 95) 'any': fn any<i32>() -> i32
+    [92; 97) 'any()': i32
+    [98; 100) '{}': ()
+    [105; 127) 'if let...y() {}': ()
+    [112; 116) '1u32': u32
+    [112; 116) '1u32': u32
+    [119; 122) 'any': fn any<u32>() -> u32
+    [119; 124) 'any()': u32
+    [125; 127) '{}': ()
+    [132; 154) 'if let...y() {}': ()
+    [139; 143) '1f32': f32
+    [139; 143) '1f32': f32
+    [146; 149) 'any': fn any<f32>() -> f32
+    [146; 151) 'any()': f32
+    [152; 154) '{}': ()
+    [159; 180) 'if let...y() {}': ()
+    [166; 169) '1.0': f64
+    [166; 169) '1.0': f64
+    [172; 175) 'any': fn any<f64>() -> f64
+    [172; 177) 'any()': f64
+    [178; 180) '{}': ()
+    [185; 207) 'if let...y() {}': ()
+    [192; 196) 'true': bool
+    [192; 196) 'true': bool
+    [199; 202) 'any': fn any<bool>() -> bool
+    [199; 204) 'any()': bool
+    [205; 207) '{}': ()
+    "###
+    );
+}
+
+#[test]
+fn infer_range_pattern() {
+    assert_snapshot!(
+        infer_with_mismatches(r#"
+fn test(x: &i32) {
+    if let 1..76 = 2u32 {}
+    if let 1..=76 = 2u32 {}
+}
+"#, true),
+        @r###"
+    [9; 10) 'x': &i32
+    [18; 76) '{     ...2 {} }': ()
+    [24; 46) 'if let...u32 {}': ()
+    [31; 36) '1..76': u32
+    [39; 43) '2u32': u32
+    [44; 46) '{}': ()
+    [51; 74) 'if let...u32 {}': ()
+    [58; 64) '1..=76': u32
+    [67; 71) '2u32': u32
+    [72; 74) '{}': ()
+    "###
+    );
+}
+
+#[test]
 fn infer_pattern_match_ergonomics() {
     assert_snapshot!(
         infer(r#"
@@ -212,6 +296,7 @@ fn test() {
     [59; 62) 'arr': [f64; _]
     [73; 81) '[1.0, a]': [f64; _]
     [74; 77) '1.0': f64
+    [74; 77) '1.0': f64
     [79; 80) 'a': f64
     [85; 111) '{     ...     }': ()
     [99; 100) 'a': f64
diff --git a/crates/ra_hir_ty/src/tests/regression.rs b/crates/ra_hir_ty/src/tests/regression.rs
index a02e3ee05..2ee9b8f10 100644
--- a/crates/ra_hir_ty/src/tests/regression.rs
+++ b/crates/ra_hir_ty/src/tests/regression.rs
@@ -206,7 +206,8 @@ pub fn compute() {
     [24; 106) 'match ...     }': ()
     [30; 37) 'nope!()': {unknown}
     [48; 94) 'SizeSk...tail }': {unknown}
-    [82; 86) 'true': {unknown}
+    [82; 86) 'true': bool
+    [82; 86) 'true': bool
     [88; 92) 'tail': {unknown}
     [98; 100) '{}': ()
     "###
diff --git a/crates/ra_hir_ty/src/tests/simple.rs b/crates/ra_hir_ty/src/tests/simple.rs
index c140bd513..a600b947d 100644
--- a/crates/ra_hir_ty/src/tests/simple.rs
+++ b/crates/ra_hir_ty/src/tests/simple.rs
@@ -948,6 +948,7 @@ fn foo() {
     [165; 247) 'match ...     }': i32
     [171; 175) 'true': bool
     [186; 190) 'true': bool
+    [186; 190) 'true': bool
     [194; 195) '3': i32
     [205; 206) '_': bool
     [210; 241) '{     ...     }': !
@@ -956,6 +957,7 @@ fn foo() {
     [263; 320) 'match ...     }': i32
     [269; 273) 'true': bool
     [284; 288) 'true': bool
+    [284; 288) 'true': bool
     [292; 293) '4': i32
     [303; 304) '_': bool
     [308; 314) 'return': !
diff --git a/crates/ra_project_model/src/cargo_workspace.rs b/crates/ra_project_model/src/cargo_workspace.rs
index c1b6e1ddc..b50cda06f 100644
--- a/crates/ra_project_model/src/cargo_workspace.rs
+++ b/crates/ra_project_model/src/cargo_workspace.rs
@@ -75,7 +75,7 @@ pub type Target = Idx<TargetData>;
 
 #[derive(Debug, Clone)]
 pub struct PackageData {
-    pub id: String,
+    pub version: String,
     pub name: String,
     pub manifest: PathBuf,
     pub targets: Vec<Target>,
@@ -174,14 +174,15 @@ impl CargoWorkspace {
         let ws_members = &meta.workspace_members;
 
         for meta_pkg in meta.packages {
-            let cargo_metadata::Package { id, edition, name, manifest_path, .. } = meta_pkg;
+            let cargo_metadata::Package { id, edition, name, manifest_path, version, .. } =
+                meta_pkg;
             let is_member = ws_members.contains(&id);
             let edition = edition
                 .parse::<Edition>()
                 .with_context(|| format!("Failed to parse edition {}", edition))?;
             let pkg = packages.alloc(PackageData {
                 name,
-                id: id.to_string(),
+                version: version.to_string(),
                 manifest: manifest_path,
                 targets: Vec::new(),
                 is_member,
@@ -256,7 +257,7 @@ impl CargoWorkspace {
         if self.is_unique(&*package.name) {
             package.name.clone()
         } else {
-            package.id.clone()
+            format!("{}:{}", package.name, package.version)
         }
     }
 
diff --git a/crates/ra_project_model/src/lib.rs b/crates/ra_project_model/src/lib.rs
index dd9c80691..0ab64a1e0 100644
--- a/crates/ra_project_model/src/lib.rs
+++ b/crates/ra_project_model/src/lib.rs
@@ -62,16 +62,16 @@ pub struct PackageRoot {
     /// Is a member of the current workspace
     is_member: bool,
 }
-
 impl PackageRoot {
-    pub fn new(path: PathBuf, is_member: bool) -> PackageRoot {
-        PackageRoot { path, is_member }
+    pub fn new_member(path: PathBuf) -> PackageRoot {
+        Self { path, is_member: true }
     }
-
-    pub fn path(&self) -> &PathBuf {
+    pub fn new_non_member(path: PathBuf) -> PackageRoot {
+        Self { path, is_member: false }
+    }
+    pub fn path(&self) -> &Path {
         &self.path
     }
-
     pub fn is_member(&self) -> bool {
         self.is_member
     }
@@ -130,70 +130,45 @@ impl ProjectWorkspace {
     pub fn to_roots(&self) -> Vec<PackageRoot> {
         match self {
             ProjectWorkspace::Json { project } => {
-                let mut roots = Vec::with_capacity(project.roots.len());
-                for root in &project.roots {
-                    roots.push(PackageRoot::new(root.path.clone(), true));
-                }
-                roots
-            }
-            ProjectWorkspace::Cargo { cargo, sysroot } => {
-                let mut roots = Vec::with_capacity(cargo.packages().len() + sysroot.crates().len());
-                for pkg in cargo.packages() {
-                    let root = cargo[pkg].root().to_path_buf();
-                    let member = cargo[pkg].is_member;
-                    roots.push(PackageRoot::new(root, member));
-                }
-                for krate in sysroot.crates() {
-                    roots.push(PackageRoot::new(sysroot[krate].root_dir().to_path_buf(), false))
-                }
-                roots
+                project.roots.iter().map(|r| PackageRoot::new_member(r.path.clone())).collect()
             }
+            ProjectWorkspace::Cargo { cargo, sysroot } => cargo
+                .packages()
+                .map(|pkg| PackageRoot {
+                    path: cargo[pkg].root().to_path_buf(),
+                    is_member: cargo[pkg].is_member,
+                })
+                .chain(sysroot.crates().map(|krate| {
+                    PackageRoot::new_non_member(sysroot[krate].root_dir().to_path_buf())
+                }))
+                .collect(),
         }
     }
 
     pub fn out_dirs(&self) -> Vec<PathBuf> {
         match self {
             ProjectWorkspace::Json { project } => {
-                let mut out_dirs = Vec::with_capacity(project.crates.len());
-                for krate in &project.crates {
-                    if let Some(out_dir) = &krate.out_dir {
-                        out_dirs.push(out_dir.to_path_buf());
-                    }
-                }
-                out_dirs
+                project.crates.iter().filter_map(|krate| krate.out_dir.as_ref()).cloned().collect()
             }
-            ProjectWorkspace::Cargo { cargo, sysroot: _sysroot } => {
-                let mut out_dirs = Vec::with_capacity(cargo.packages().len());
-                for pkg in cargo.packages() {
-                    if let Some(out_dir) = &cargo[pkg].out_dir {
-                        out_dirs.push(out_dir.to_path_buf());
-                    }
-                }
-                out_dirs
+            ProjectWorkspace::Cargo { cargo, sysroot: _ } => {
+                cargo.packages().filter_map(|pkg| cargo[pkg].out_dir.as_ref()).cloned().collect()
             }
         }
     }
 
     pub fn proc_macro_dylib_paths(&self) -> Vec<PathBuf> {
         match self {
-            ProjectWorkspace::Json { project } => {
-                let mut proc_macro_dylib_paths = Vec::with_capacity(project.crates.len());
-                for krate in &project.crates {
-                    if let Some(out_dir) = &krate.proc_macro_dylib_path {
-                        proc_macro_dylib_paths.push(out_dir.to_path_buf());
-                    }
-                }
-                proc_macro_dylib_paths
-            }
-            ProjectWorkspace::Cargo { cargo, sysroot: _sysroot } => {
-                let mut proc_macro_dylib_paths = Vec::with_capacity(cargo.packages().len());
-                for pkg in cargo.packages() {
-                    if let Some(dylib_path) = &cargo[pkg].proc_macro_dylib_path {
-                        proc_macro_dylib_paths.push(dylib_path.to_path_buf());
-                    }
-                }
-                proc_macro_dylib_paths
-            }
+            ProjectWorkspace::Json { project } => project
+                .crates
+                .iter()
+                .filter_map(|krate| krate.proc_macro_dylib_path.as_ref())
+                .cloned()
+                .collect(),
+            ProjectWorkspace::Cargo { cargo, sysroot: _sysroot } => cargo
+                .packages()
+                .filter_map(|pkg| cargo[pkg].proc_macro_dylib_path.as_ref())
+                .cloned()
+                .collect(),
         }
     }
 
@@ -216,10 +191,12 @@ impl ProjectWorkspace {
         let mut crate_graph = CrateGraph::default();
         match self {
             ProjectWorkspace::Json { project } => {
-                let mut crates = FxHashMap::default();
-                for (id, krate) in project.crates.iter().enumerate() {
-                    let crate_id = json_project::CrateId(id);
-                    if let Some(file_id) = load(&krate.root_module) {
+                let crates: FxHashMap<_, _> = project
+                    .crates
+                    .iter()
+                    .enumerate()
+                    .filter_map(|(seq_index, krate)| {
+                        let file_id = load(&krate.root_module)?;
                         let edition = match krate.edition {
                             json_project::Edition::Edition2015 => Edition::Edition2015,
                             json_project::Edition::Edition2018 => Edition::Edition2018,
@@ -249,8 +226,8 @@ impl ProjectWorkspace {
                             .clone()
                             .map(|it| proc_macro_client.by_dylib_path(&it));
                         // FIXME: No crate name in json definition such that we cannot add OUT_DIR to env
-                        crates.insert(
-                            crate_id,
+                        Some((
+                            json_project::CrateId(seq_index),
                             crate_graph.add_crate_root(
                                 file_id,
                                 edition,
@@ -261,9 +238,9 @@ impl ProjectWorkspace {
                                 extern_source,
                                 proc_macro.unwrap_or_default(),
                             ),
-                        );
-                    }
-                }
+                        ))
+                    })
+                    .collect();
 
                 for (id, krate) in project.crates.iter().enumerate() {
                     for dep in &krate.deps {
@@ -287,9 +264,11 @@ impl ProjectWorkspace {
                 }
             }
             ProjectWorkspace::Cargo { cargo, sysroot } => {
-                let mut sysroot_crates = FxHashMap::default();
-                for krate in sysroot.crates() {
-                    if let Some(file_id) = load(&sysroot[krate].root) {
+                let sysroot_crates: FxHashMap<_, _> = sysroot
+                    .crates()
+                    .filter_map(|krate| {
+                        let file_id = load(&sysroot[krate].root)?;
+
                         // Crates from sysroot have `cfg(test)` disabled
                         let cfg_options = {
                             let mut opts = default_cfg_options.clone();
@@ -300,22 +279,22 @@ impl ProjectWorkspace {
                         let env = Env::default();
                         let extern_source = ExternSource::default();
                         let proc_macro = vec![];
+                        let crate_name = CrateName::new(&sysroot[krate].name)
+                            .expect("Sysroot crate names should not contain dashes");
 
                         let crate_id = crate_graph.add_crate_root(
                             file_id,
                             Edition::Edition2018,
-                            Some(
-                                CrateName::new(&sysroot[krate].name)
-                                    .expect("Sysroot crate names should not contain dashes"),
-                            ),
+                            Some(crate_name),
                             cfg_options,
                             env,
                             extern_source,
                             proc_macro,
                         );
-                        sysroot_crates.insert(krate, crate_id);
-                    }
-                }
+                        Some((krate, crate_id))
+                    })
+                    .collect();
+
                 for from in sysroot.crates() {
                     for &to in sysroot[from].deps.iter() {
                         let name = &sysroot[to].name;
diff --git a/crates/ra_syntax/src/ast/make.rs b/crates/ra_syntax/src/ast/make.rs
index dbb9c8a9b..f39559e9e 100644
--- a/crates/ra_syntax/src/ast/make.rs
+++ b/crates/ra_syntax/src/ast/make.rs
@@ -22,7 +22,8 @@ pub fn path_unqualified(segment: ast::PathSegment) -> ast::Path {
 pub fn path_qualified(qual: ast::Path, segment: ast::PathSegment) -> ast::Path {
     path_from_text(&format!("{}::{}", qual, segment))
 }
-fn path_from_text(text: &str) -> ast::Path {
+
+pub fn path_from_text(text: &str) -> ast::Path {
     ast_from_text(text)
 }
 
diff --git a/crates/rust-analyzer/src/cli/load_cargo.rs b/crates/rust-analyzer/src/cli/load_cargo.rs
index 2c0bde920..69133e4e4 100644
--- a/crates/rust-analyzer/src/cli/load_cargo.rs
+++ b/crates/rust-analyzer/src/cli/load_cargo.rs
@@ -36,8 +36,7 @@ pub(crate) fn load_cargo(
     extern_dirs.extend(ws.out_dirs());
 
     let mut project_roots = ws.to_roots();
-    project_roots
-        .extend(extern_dirs.iter().map(|path| PackageRoot::new(path.to_path_buf(), false)));
+    project_roots.extend(extern_dirs.iter().cloned().map(PackageRoot::new_non_member));
 
     let (sender, receiver) = unbounded();
     let sender = Box::new(move |t| sender.send(t).unwrap());
@@ -46,7 +45,7 @@ pub(crate) fn load_cargo(
             .iter()
             .map(|pkg_root| {
                 RootEntry::new(
-                    pkg_root.path().clone(),
+                    pkg_root.path().to_owned(),
                     RustPackageFilterBuilder::default()
                         .set_member(pkg_root.is_member())
                         .into_vfs_filter(),
@@ -58,12 +57,12 @@ pub(crate) fn load_cargo(
     );
 
     let source_roots = roots
-        .iter()
-        .map(|&vfs_root| {
+        .into_iter()
+        .map(|vfs_root| {
             let source_root_id = vfs_root_to_id(vfs_root);
             let project_root = project_roots
                 .iter()
-                .find(|it| it.path() == &vfs.root2path(vfs_root))
+                .find(|it| it.path() == vfs.root2path(vfs_root))
                 .unwrap()
                 .clone();
             (source_root_id, project_root)
diff --git a/crates/rust-analyzer/src/config.rs b/crates/rust-analyzer/src/config.rs
index 3c8f55f1e..04f5bb473 100644
--- a/crates/rust-analyzer/src/config.rs
+++ b/crates/rust-analyzer/src/config.rs
@@ -16,21 +16,33 @@ use serde::Deserialize;
 #[derive(Debug, Clone)]
 pub struct Config {
     pub client_caps: ClientCapsConfig,
-    pub publish_decorations: bool,
+
+    pub with_sysroot: bool,
     pub publish_diagnostics: bool,
+    pub lru_capacity: Option<usize>,
+    pub proc_macro_srv: Option<String>,
+    pub files: FilesConfig,
     pub notifications: NotificationsConfig,
+
+    pub cargo: CargoConfig,
+    pub rustfmt: RustfmtConfig,
+    pub check: Option<FlycheckConfig>,
+
     pub inlay_hints: InlayHintsConfig,
     pub completion: CompletionConfig,
     pub call_info_full: bool,
-    pub rustfmt: RustfmtConfig,
-    pub check: Option<FlycheckConfig>,
-    pub vscode_lldb: bool,
-    pub proc_macro_srv: Option<String>,
-    pub lru_capacity: Option<usize>,
-    pub use_client_watching: bool,
-    pub exclude_globs: Vec<String>,
-    pub cargo: CargoConfig,
-    pub with_sysroot: bool,
+}
+
+#[derive(Debug, Clone)]
+pub struct FilesConfig {
+    pub watcher: FilesWatcher,
+    pub exclude: Vec<String>,
+}
+
+#[derive(Debug, Clone)]
+pub enum FilesWatcher {
+    Client,
+    Notify,
 }
 
 #[derive(Debug, Clone)]
@@ -60,13 +72,26 @@ pub struct ClientCapsConfig {
 impl Default for Config {
     fn default() -> Self {
         Config {
-            publish_decorations: false,
+            client_caps: ClientCapsConfig::default(),
+
+            with_sysroot: true,
             publish_diagnostics: true,
+            lru_capacity: None,
+            proc_macro_srv: None,
+            files: FilesConfig { watcher: FilesWatcher::Notify, exclude: Vec::new() },
             notifications: NotificationsConfig {
                 workspace_loaded: true,
                 cargo_toml_not_found: true,
             },
-            client_caps: ClientCapsConfig::default(),
+
+            cargo: CargoConfig::default(),
+            rustfmt: RustfmtConfig::Rustfmt { extra_args: Vec::new() },
+            check: Some(FlycheckConfig::CargoCommand {
+                command: "check".to_string(),
+                all_targets: true,
+                extra_args: Vec::new(),
+            }),
+
             inlay_hints: InlayHintsConfig {
                 type_hints: true,
                 parameter_hints: true,
@@ -79,19 +104,6 @@ impl Default for Config {
                 add_call_argument_snippets: true,
             },
             call_info_full: true,
-            rustfmt: RustfmtConfig::Rustfmt { extra_args: Vec::new() },
-            check: Some(FlycheckConfig::CargoCommand {
-                command: "check".to_string(),
-                all_targets: true,
-                extra_args: Vec::new(),
-            }),
-            vscode_lldb: false,
-            proc_macro_srv: None,
-            lru_capacity: None,
-            use_client_watching: false,
-            exclude_globs: Vec::new(),
-            cargo: CargoConfig::default(),
-            with_sysroot: true,
         }
     }
 }
@@ -105,46 +117,61 @@ impl Config {
         *self = Default::default();
         self.client_caps = client_caps;
 
-        set(value, "/publishDecorations", &mut self.publish_decorations);
-        set(value, "/excludeGlobs", &mut self.exclude_globs);
-        set(value, "/useClientWatching", &mut self.use_client_watching);
+        set(value, "/withSysroot", &mut self.with_sysroot);
+        set(value, "/featureFlags/lsp.diagnostics", &mut self.publish_diagnostics);
         set(value, "/lruCapacity", &mut self.lru_capacity);
-
-        set(value, "/inlayHintsType", &mut self.inlay_hints.type_hints);
-        set(value, "/inlayHintsParameter", &mut self.inlay_hints.parameter_hints);
-        set(value, "/inlayHintsChaining", &mut self.inlay_hints.chaining_hints);
-        set(value, "/inlayHintsMaxLength", &mut self.inlay_hints.max_length);
-
-        if let Some(false) = get(value, "cargo_watch_enable") {
+        if let Some(watcher) =  get::<String>(value, "/files/watcher") {
+            self.files.watcher = match watcher.as_str() {
+                "client" => FilesWatcher::Client,
+                "notify"| _ => FilesWatcher::Notify,
+            }
+        }
+        set(value, "/notifications/workspaceLoaded", &mut self.notifications.workspace_loaded);
+        set(value, "/notifications/cargoTomlNotFound", &mut self.notifications.cargo_toml_not_found);
+
+        set(value, "/cargo/noDefaultFeatures", &mut self.cargo.no_default_features);
+        set(value, "/cargo/allFeatures", &mut self.cargo.all_features);
+        set(value, "/cargo/features", &mut self.cargo.features);
+        set(value, "/cargo/loadOutDirsFromCheck", &mut self.cargo.load_out_dirs_from_check);
+        if let Some(mut args) = get::<Vec<String>>(value, "/rustfmt/overrideCommand") {
+            if !args.is_empty() {
+                let command = args.remove(0);
+                self.rustfmt = RustfmtConfig::CustomCommand {
+                    command,
+                    args,
+                }
+            }
+        } else if let RustfmtConfig::Rustfmt { extra_args } = &mut self.rustfmt {
+            set(value, "/rustfmt/extraArgs", extra_args);
+        }
+        if let Some(false) = get(value, "/checkOnSave/enable") {
             self.check = None
         } else {
-            if let Some(FlycheckConfig::CargoCommand { command, extra_args, all_targets }) = &mut self.check
+            if let Some(mut args) = get::<Vec<String>>(value, "/checkOnSave/overrideCommand") {
+                if !args.is_empty() {
+                    let command = args.remove(0);
+                    self.check = Some(FlycheckConfig::CustomCommand {
+                        command,
+                        args,
+                    })
+                }
+
+            } else if let Some(FlycheckConfig::CargoCommand { command, extra_args, all_targets }) = &mut self.check
             {
-                set(value, "/cargoWatchArgs", extra_args);
-                set(value, "/cargoWatchCommand", command);
-                set(value, "/cargoWatchAllTargets", all_targets);
+                set(value, "/checkOnSave/extraArgs", extra_args);
+                set(value, "/checkOnSave/command", command);
+                set(value, "/checkOnSave/allTargets", all_targets);
             }
         };
 
-        set(value, "/withSysroot", &mut self.with_sysroot);
-        if let RustfmtConfig::Rustfmt { extra_args } = &mut self.rustfmt {
-            set(value, "/rustfmtArgs", extra_args);
-        }
-
-        set(value, "/cargoFeatures/noDefaultFeatures", &mut self.cargo.no_default_features);
-        set(value, "/cargoFeatures/allFeatures", &mut self.cargo.all_features);
-        set(value, "/cargoFeatures/features", &mut self.cargo.features);
-        set(value, "/cargoFeatures/loadOutDirsFromCheck", &mut self.cargo.load_out_dirs_from_check);
-
-        set(value, "/vscodeLldb", &mut self.vscode_lldb);
-
-        set(value, "/featureFlags/lsp.diagnostics", &mut self.publish_diagnostics);
-        set(value, "/featureFlags/notifications.workspace-loaded", &mut self.notifications.workspace_loaded);
-        set(value, "/featureFlags/notifications.cargo-toml-not-found", &mut self.notifications.cargo_toml_not_found);
-        set(value, "/featureFlags/completion.enable-postfix", &mut self.completion.enable_postfix_completions);
-        set(value, "/featureFlags/completion.insertion.add-call-parenthesis", &mut self.completion.add_call_parenthesis);
-        set(value, "/featureFlags/completion.insertion.add-argument-snippets", &mut self.completion.add_call_argument_snippets);
-        set(value, "/featureFlags/call-info.full", &mut self.call_info_full);
+        set(value, "/inlayHints/typeHints", &mut self.inlay_hints.type_hints);
+        set(value, "/inlayHints/parameterHints", &mut self.inlay_hints.parameter_hints);
+        set(value, "/inlayHints/chainingHints", &mut self.inlay_hints.chaining_hints);
+        set(value, "/inlayHints/maxLength", &mut self.inlay_hints.max_length);
+        set(value, "/completion/postfix/enable", &mut self.completion.enable_postfix_completions);
+        set(value, "/completion/addCallParenthesis", &mut self.completion.add_call_parenthesis);
+        set(value, "/completion/addCallArgumentSnippets", &mut self.completion.add_call_argument_snippets);
+        set(value, "/callInfo/full", &mut self.call_info_full);
 
         log::info!("Config::update() = {:#?}", self);
 
diff --git a/crates/rust-analyzer/src/main_loop.rs b/crates/rust-analyzer/src/main_loop.rs
index 45ae0ad9d..8d1429196 100644
--- a/crates/rust-analyzer/src/main_loop.rs
+++ b/crates/rust-analyzer/src/main_loop.rs
@@ -23,6 +23,7 @@ use lsp_types::{
 use ra_flycheck::{url_from_path_with_drive_lowercasing, CheckTask};
 use ra_ide::{Canceled, FileId, LibraryData, SourceRootId};
 use ra_prof::profile;
+use ra_project_model::{PackageRoot, ProjectWorkspace};
 use ra_vfs::{VfsFile, VfsTask, Watch};
 use relative_path::RelativePathBuf;
 use rustc_hash::FxHashSet;
@@ -30,7 +31,7 @@ use serde::{de::DeserializeOwned, Serialize};
 use threadpool::ThreadPool;
 
 use crate::{
-    config::Config,
+    config::{Config, FilesWatcher},
     diagnostics::DiagnosticTask,
     main_loop::{
         pending_requests::{PendingRequest, PendingRequests},
@@ -40,7 +41,6 @@ use crate::{
     world::{WorldSnapshot, WorldState},
     Result,
 };
-use req::ConfigurationParams;
 
 #[derive(Debug)]
 pub struct LspError {
@@ -122,17 +122,18 @@ pub fn main_loop(ws_roots: Vec<PathBuf>, config: Config, connection: Connection)
         };
 
         let globs = config
-            .exclude_globs
+            .files
+            .exclude
             .iter()
             .map(|glob| crate::vfs_glob::Glob::new(glob))
             .collect::<std::result::Result<Vec<_>, _>>()?;
 
-        if config.use_client_watching {
+        if let FilesWatcher::Client = config.files.watcher {
             let registration_options = req::DidChangeWatchedFilesRegistrationOptions {
                 watchers: workspaces
                     .iter()
-                    .flat_map(|ws| ws.to_roots())
-                    .filter(|root| root.is_member())
+                    .flat_map(ProjectWorkspace::to_roots)
+                    .filter(PackageRoot::is_member)
                     .map(|root| format!("{}/**/*.rs", root.path().display()))
                     .map(|glob_pattern| req::FileSystemWatcher { glob_pattern, kind: None })
                     .collect(),
@@ -153,7 +154,7 @@ pub fn main_loop(ws_roots: Vec<PathBuf>, config: Config, connection: Connection)
             workspaces,
             config.lru_capacity,
             &globs,
-            Watch(!config.use_client_watching),
+            Watch(matches!(config.files.watcher, FilesWatcher::Notify)),
             config,
         )
     };
@@ -250,9 +251,7 @@ impl fmt::Debug for Event {
                 }
             }
             Event::Task(Task::Notify(not)) => {
-                if notification_is::<req::PublishDecorations>(not)
-                    || notification_is::<req::PublishDiagnostics>(not)
-                {
+                if notification_is::<req::PublishDiagnostics>(not) {
                     return debug_verbose_not(not, f);
                 }
             }
@@ -427,7 +426,6 @@ fn loop_turn(
         update_file_notifications_on_threadpool(
             pool,
             world_state.snapshot(),
-            world_state.config.publish_decorations,
             task_sender.clone(),
             loop_state.subscriptions.subscriptions(),
         )
@@ -508,7 +506,6 @@ fn on_request(
         .on::<req::GotoTypeDefinition>(handlers::handle_goto_type_definition)?
         .on::<req::ParentModule>(handlers::handle_parent_module)?
         .on::<req::Runnables>(handlers::handle_runnables)?
-        .on::<req::DecorationsRequest>(handlers::handle_decorations)?
         .on::<req::Completion>(handlers::handle_completion)?
         .on::<req::CodeActionRequest>(handlers::handle_code_action)?
         .on::<req::CodeLensRequest>(handlers::handle_code_lens)?
@@ -611,7 +608,12 @@ fn on_notification(
             let request_id = loop_state.next_request_id();
             let request = request_new::<req::WorkspaceConfiguration>(
                 request_id.clone(),
-                ConfigurationParams::default(),
+                req::ConfigurationParams {
+                    items: vec![req::ConfigurationItem {
+                        scope_uri: None,
+                        section: Some("rust-analyzer".to_string()),
+                    }],
+                },
             );
             msg_sender.send(request.into())?;
             loop_state.configuration_request_id = Some(request_id);
@@ -884,15 +886,13 @@ where
 fn update_file_notifications_on_threadpool(
     pool: &ThreadPool,
     world: WorldSnapshot,
-    publish_decorations: bool,
     task_sender: Sender<Task>,
     subscriptions: Vec<FileId>,
 ) {
     log::trace!("updating notifications for {:?}", subscriptions);
-    let publish_diagnostics = world.config.publish_diagnostics;
-    pool.execute(move || {
-        for file_id in subscriptions {
-            if publish_diagnostics {
+    if world.config.publish_diagnostics {
+        pool.execute(move || {
+            for file_id in subscriptions {
                 match handlers::publish_diagnostics(&world, file_id) {
                     Err(e) => {
                         if !is_canceled(&e) {
@@ -904,21 +904,8 @@ fn update_file_notifications_on_threadpool(
                     }
                 }
             }
-            if publish_decorations {
-                match handlers::publish_decorations(&world, file_id) {
-                    Err(e) => {
-                        if !is_canceled(&e) {
-                            log::error!("failed to compute decorations: {:?}", e);
-                        }
-                    }
-                    Ok(params) => {
-                        let not = notification_new::<req::PublishDecorations>(params);
-                        task_sender.send(Task::Notify(not)).unwrap();
-                    }
-                }
-            }
-        }
-    });
+        })
+    }
 }
 
 pub fn show_message(typ: req::MessageType, message: impl Into<String>, sender: &Sender<Message>) {
diff --git a/crates/rust-analyzer/src/main_loop/handlers.rs b/crates/rust-analyzer/src/main_loop/handlers.rs
index 23e48c089..b207f0764 100644
--- a/crates/rust-analyzer/src/main_loop/handlers.rs
+++ b/crates/rust-analyzer/src/main_loop/handlers.rs
@@ -38,7 +38,7 @@ use crate::{
     },
     diagnostics::DiagnosticTask,
     from_json,
-    req::{self, Decoration, InlayHint, InlayHintsParams},
+    req::{self, InlayHint, InlayHintsParams},
     semantic_tokens::SemanticTokensBuilder,
     world::WorldSnapshot,
     LspError, Result,
@@ -389,15 +389,6 @@ pub fn handle_runnables(
     Ok(res)
 }
 
-pub fn handle_decorations(
-    world: WorldSnapshot,
-    params: TextDocumentIdentifier,
-) -> Result<Vec<Decoration>> {
-    let _p = profile("handle_decorations");
-    let file_id = params.try_conv_with(&world)?;
-    highlight(&world, file_id)
-}
-
 pub fn handle_completion(
     world: WorldSnapshot,
     params: req::CompletionParams,
@@ -819,23 +810,21 @@ pub fn handle_code_lens(
         };
         lenses.push(lens);
 
-        if world.config.vscode_lldb {
-            if r.args[0] == "run" {
-                r.args[0] = "build".into();
-            } else {
-                r.args.push("--no-run".into());
-            }
-            let debug_lens = CodeLens {
-                range: r.range,
-                command: Some(Command {
-                    title: "Debug".into(),
-                    command: "rust-analyzer.debugSingle".into(),
-                    arguments: Some(vec![to_value(r).unwrap()]),
-                }),
-                data: None,
-            };
-            lenses.push(debug_lens);
+        if r.args[0] == "run" {
+            r.args[0] = "build".into();
+        } else {
+            r.args.push("--no-run".into());
         }
+        let debug_lens = CodeLens {
+            range: r.range,
+            command: Some(Command {
+                title: "Debug".into(),
+                command: "rust-analyzer.debugSingle".into(),
+                arguments: Some(vec![to_value(r).unwrap()]),
+            }),
+            data: None,
+        };
+        lenses.push(debug_lens);
     }
 
     // Handle impls
@@ -970,15 +959,6 @@ pub fn publish_diagnostics(world: &WorldSnapshot, file_id: FileId) -> Result<Dia
     Ok(DiagnosticTask::SetNative(file_id, diagnostics))
 }
 
-pub fn publish_decorations(
-    world: &WorldSnapshot,
-    file_id: FileId,
-) -> Result<req::PublishDecorationsParams> {
-    let _p = profile("publish_decorations");
-    let uri = world.file_id_to_uri(file_id)?;
-    Ok(req::PublishDecorationsParams { uri, decorations: highlight(&world, file_id)? })
-}
-
 fn to_lsp_runnable(
     world: &WorldSnapshot,
     file_id: FileId,
@@ -1008,21 +988,6 @@ fn to_lsp_runnable(
     })
 }
 
-fn highlight(world: &WorldSnapshot, file_id: FileId) -> Result<Vec<Decoration>> {
-    let line_index = world.analysis().file_line_index(file_id)?;
-    let res = world
-        .analysis()
-        .highlight(file_id)?
-        .into_iter()
-        .map(|h| Decoration {
-            range: h.range.conv_with(&line_index),
-            tag: h.highlight.to_string(),
-            binding_hash: h.binding_hash.map(|x| x.to_string()),
-        })
-        .collect();
-    Ok(res)
-}
-
 pub fn handle_inlay_hints(
     world: WorldSnapshot,
     params: InlayHintsParams,
diff --git a/crates/rust-analyzer/src/main_loop/subscriptions.rs b/crates/rust-analyzer/src/main_loop/subscriptions.rs
index bee6437cf..2c76418be 100644
--- a/crates/rust-analyzer/src/main_loop/subscriptions.rs
+++ b/crates/rust-analyzer/src/main_loop/subscriptions.rs
@@ -17,6 +17,6 @@ impl Subscriptions {
         self.subs.remove(&file_id);
     }
     pub(crate) fn subscriptions(&self) -> Vec<FileId> {
-        self.subs.iter().cloned().collect()
+        self.subs.iter().copied().collect()
     }
 }
diff --git a/crates/rust-analyzer/src/req.rs b/crates/rust-analyzer/src/req.rs
index 994f0ed61..b8b627e28 100644
--- a/crates/rust-analyzer/src/req.rs
+++ b/crates/rust-analyzer/src/req.rs
@@ -1,13 +1,13 @@
 //! Defines `rust-analyzer` specific custom messages.
 
-use lsp_types::{Location, Position, Range, TextDocumentIdentifier, Url};
+use lsp_types::{Location, Position, Range, TextDocumentIdentifier};
 use rustc_hash::FxHashMap;
 use serde::{Deserialize, Serialize};
 
 pub use lsp_types::{
     notification::*, request::*, ApplyWorkspaceEditParams, CodeActionParams, CodeLens,
-    CodeLensParams, CompletionParams, CompletionResponse, ConfigurationParams, DiagnosticTag,
-    DidChangeConfigurationParams, DidChangeWatchedFilesParams,
+    CodeLensParams, CompletionParams, CompletionResponse, ConfigurationItem, ConfigurationParams,
+    DiagnosticTag, DidChangeConfigurationParams, DidChangeWatchedFilesParams,
     DidChangeWatchedFilesRegistrationOptions, DocumentOnTypeFormattingParams, DocumentSymbolParams,
     DocumentSymbolResponse, FileSystemWatcher, Hover, InitializeResult, MessageType,
     PartialResultParams, ProgressParams, ProgressParamsValue, ProgressToken,
@@ -86,36 +86,6 @@ pub struct FindMatchingBraceParams {
     pub offsets: Vec<Position>,
 }
 
-pub enum DecorationsRequest {}
-
-impl Request for DecorationsRequest {
-    type Params = TextDocumentIdentifier;
-    type Result = Vec<Decoration>;
-    const METHOD: &'static str = "rust-analyzer/decorationsRequest";
-}
-
-pub enum PublishDecorations {}
-
-impl Notification for PublishDecorations {
-    type Params = PublishDecorationsParams;
-    const METHOD: &'static str = "rust-analyzer/publishDecorations";
-}
-
-#[derive(Deserialize, Serialize, Debug)]
-#[serde(rename_all = "camelCase")]
-pub struct PublishDecorationsParams {
-    pub uri: Url,
-    pub decorations: Vec<Decoration>,
-}
-
-#[derive(Deserialize, Serialize, Debug)]
-#[serde(rename_all = "camelCase")]
-pub struct Decoration {
-    pub range: Range,
-    pub tag: String,
-    pub binding_hash: Option<String>,
-}
-
 pub enum ParentModule {}
 
 impl Request for ParentModule {
diff --git a/crates/rust-analyzer/src/vfs_glob.rs b/crates/rust-analyzer/src/vfs_glob.rs
index 91b33f94e..ff37a7008 100644
--- a/crates/rust-analyzer/src/vfs_glob.rs
+++ b/crates/rust-analyzer/src/vfs_glob.rs
@@ -29,10 +29,14 @@ impl RustPackageFilterBuilder {
         self.is_member = is_member;
         self
     }
-    pub fn exclude(mut self, glob: Glob) -> RustPackageFilterBuilder {
-        self.exclude.add(glob);
+
+    pub fn exclude(mut self, globs: impl IntoIterator<Item = Glob>) -> RustPackageFilterBuilder {
+        for glob in globs.into_iter() {
+            self.exclude.add(glob);
+        }
         self
     }
+
     pub fn into_vfs_filter(self) -> Box<dyn Filter> {
         let RustPackageFilterBuilder { is_member, mut exclude } = self;
         for &glob in ALWAYS_IGNORED {
@@ -87,7 +91,7 @@ fn test_globs() {
 
     let filter = RustPackageFilterBuilder::default()
         .set_member(true)
-        .exclude(Glob::new("src/llvm-project/**").unwrap())
+        .exclude(std::iter::once(Glob::new("src/llvm-project/**").unwrap()))
         .into_vfs_filter();
 
     assert!(!filter.include_dir(RelativePath::new("src/llvm-project/clang")));
diff --git a/crates/rust-analyzer/src/world.rs b/crates/rust-analyzer/src/world.rs
index 5674f42ef..365f57d8c 100644
--- a/crates/rust-analyzer/src/world.rs
+++ b/crates/rust-analyzer/src/world.rs
@@ -87,44 +87,35 @@ impl WorldState {
     ) -> WorldState {
         let mut change = AnalysisChange::new();
 
-        let mut roots = Vec::new();
-        roots.extend(folder_roots.iter().map(|path| {
-            let mut filter = RustPackageFilterBuilder::default().set_member(true);
-            for glob in exclude_globs.iter() {
-                filter = filter.exclude(glob.clone());
-            }
-            RootEntry::new(path.clone(), filter.into_vfs_filter())
-        }));
-        for ws in workspaces.iter() {
-            roots.extend(ws.to_roots().into_iter().map(|pkg_root| {
-                let mut filter =
-                    RustPackageFilterBuilder::default().set_member(pkg_root.is_member());
-                for glob in exclude_globs.iter() {
-                    filter = filter.exclude(glob.clone());
-                }
-                RootEntry::new(pkg_root.path().clone(), filter.into_vfs_filter())
-            }));
-        }
-
-        let mut extern_dirs = FxHashSet::default();
-        for ws in workspaces.iter() {
-            extern_dirs.extend(ws.out_dirs());
-        }
-
-        let mut extern_source_roots = FxHashMap::default();
-
-        roots.extend(extern_dirs.iter().map(|path| {
-            let mut filter = RustPackageFilterBuilder::default().set_member(false);
-            for glob in exclude_globs.iter() {
-                filter = filter.exclude(glob.clone());
-            }
-            RootEntry::new(PathBuf::from(&path), filter.into_vfs_filter())
-        }));
+        let extern_dirs: FxHashSet<_> =
+            workspaces.iter().flat_map(ProjectWorkspace::out_dirs).collect();
+
+        let roots: Vec<_> = {
+            let create_filter = |is_member| {
+                RustPackageFilterBuilder::default()
+                    .set_member(is_member)
+                    .exclude(exclude_globs.iter().cloned())
+                    .into_vfs_filter()
+            };
+            folder_roots
+                .iter()
+                .map(|path| RootEntry::new(path.clone(), create_filter(true)))
+                .chain(workspaces.iter().flat_map(ProjectWorkspace::to_roots).map(|pkg_root| {
+                    RootEntry::new(pkg_root.path().to_owned(), create_filter(pkg_root.is_member()))
+                }))
+                .chain(
+                    extern_dirs
+                        .iter()
+                        .map(|path| RootEntry::new(path.to_owned(), create_filter(false))),
+                )
+                .collect()
+        };
 
         let (task_sender, task_receiver) = unbounded();
         let task_sender = Box::new(move |t| task_sender.send(t).unwrap());
         let (mut vfs, vfs_roots) = Vfs::new(roots, task_sender, watch);
 
+        let mut extern_source_roots = FxHashMap::default();
         for r in vfs_roots {
             let vfs_root_path = vfs.root2path(r);
             let is_local = folder_roots.iter().any(|it| vfs_root_path.starts_with(it));