9 files changed, 332 insertions, 283 deletions

diff --git a/crates/ra_analysis/src/db.rs b/crates/ra_analysis/src/db.rs
index c69577233..042dde1ac 100644
--- a/crates/ra_analysis/src/db.rs
+++ b/crates/ra_analysis/src/db.rs
@@ -1,17 +1,18 @@
-use std::{
-    fmt,
-    sync::Arc,
-    hash::{Hash, Hasher},
-};
-use salsa;
-use rustc_hash::FxHashSet;
-use ra_syntax::File;
-use ra_editor::{LineIndex};
 use crate::{
+    module_map::{ModuleDescriptorQuery, ModuleTreeQuery, ModulesDatabase},
     symbol_index::SymbolIndex,
-    module_map::{ModulesDatabase, ModuleTreeQuery, ModuleDescriptorQuery},
     FileId, FileResolverImp,
 };
+use ra_editor::LineIndex;
+use ra_syntax::File;
+use rustc_hash::FxHashSet;
+use salsa;
+
+use std::{
+    fmt,
+    hash::{Hash, Hasher},
+    sync::Arc,
+};
 
 #[derive(Default)]
 pub(crate) struct RootDatabase {
diff --git a/crates/ra_analysis/src/descriptors.rs b/crates/ra_analysis/src/descriptors.rs
index 8d9f38ca5..6f26f9935 100644
--- a/crates/ra_analysis/src/descriptors.rs
+++ b/crates/ra_analysis/src/descriptors.rs
@@ -1,41 +1,34 @@
-use std::{
-    collections::BTreeMap,
-};
-use relative_path::RelativePathBuf;
+use crate::{imp::FileResolverImp, FileId};
 use ra_syntax::{
+    ast::{self, AstNode, NameOwner},
+    text_utils::is_subrange,
     SmolStr,
-    ast::{self, NameOwner, AstNode},
-    text_utils::is_subrange
-};
-use crate::{
-    FileId,
-    imp::FileResolverImp,
 };
+use relative_path::RelativePathBuf;
+
+use std::collections::BTreeMap;
 
 #[derive(Debug, PartialEq, Eq, Hash)]
 pub struct ModuleDescriptor {
-    pub submodules: Vec<Submodule>
+    pub submodules: Vec<Submodule>,
 }
 
 impl ModuleDescriptor {
     pub fn new(root: ast::Root) -> ModuleDescriptor {
-        let submodules = modules(root)
-            .map(|(name, _)| Submodule { name })
-            .collect();
+        let submodules = modules(root).map(|(name, _)| Submodule { name }).collect();
 
-        ModuleDescriptor { submodules } }
+        ModuleDescriptor { submodules }
+    }
 }
 
-fn modules<'a>(root: ast::Root<'a>) -> impl Iterator<Item=(SmolStr, ast::Module<'a>)> {
-    root
-        .modules()
-        .filter_map(|module| {
-            let name = module.name()?.text();
-            if !module.has_semi() {
-                return None;
-            }
-            Some((name, module))
-        })
+fn modules<'a>(root: ast::Root<'a>) -> impl Iterator<Item = (SmolStr, ast::Module<'a>)> {
+    root.modules().filter_map(|module| {
+        let name = module.name()?.text();
+        if !module.has_semi() {
+            return None;
+        }
+        Some((name, module))
+    })
 }
 
 #[derive(Clone, Hash, PartialEq, Eq, Debug)]
@@ -56,7 +49,7 @@ struct Node(usize);
 struct NodeData {
     file_id: FileId,
     links: Vec<Link>,
-    parents: Vec<Link>
+    parents: Vec<Link>,
 }
 
 #[derive(Clone, Copy, PartialEq, Eq, Hash, Debug)]
@@ -69,7 +62,6 @@ struct LinkData {
     problem: Option<Problem>,
 }
 
-
 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
 pub enum Problem {
     UnresolvedModule {
@@ -78,16 +70,18 @@ pub enum Problem {
     NotDirOwner {
         move_to: RelativePathBuf,
         candidate: RelativePathBuf,
-    }
+    },
 }
 
 impl ModuleTreeDescriptor {
     pub(crate) fn new<'a>(
-        files: impl Iterator<Item=(FileId, &'a ModuleDescriptor)> + Clone,
+        files: impl Iterator<Item = (FileId, &'a ModuleDescriptor)> + Clone,
         file_resolver: &FileResolverImp,
     ) -> ModuleTreeDescriptor {
         let mut file_id2node = BTreeMap::new();
-        let mut nodes: Vec<NodeData> = files.clone().enumerate()
+        let mut nodes: Vec<NodeData> = files
+            .clone()
+            .enumerate()
             .map(|(idx, (file_id, _))| {
                 file_id2node.insert(file_id, Node(idx));
                 NodeData {
@@ -120,20 +114,19 @@ impl ModuleTreeDescriptor {
                     points_to,
                     problem,
                 })
-
             }
         }
 
         ModuleTreeDescriptor {
-            nodes, links, file_id2node
+            nodes,
+            links,
+            file_id2node,
         }
     }
 
     pub(crate) fn parent_modules(&self, file_id: FileId) -> Vec<Link> {
         let node = self.file_id2node[&file_id];
-        self.node(node)
-            .parents
-            .clone()
+        self.node(node).parents.clone()
     }
     pub(crate) fn child_module_by_name(&self, file_id: FileId, name: &str) -> Vec<FileId> {
         let node = self.file_id2node[&file_id];
@@ -141,10 +134,18 @@ impl ModuleTreeDescriptor {
             .links
             .iter()
             .filter(|it| it.name(self) == name)
-            .flat_map(|link| link.points_to(self).iter().map(|&node| self.node(node).file_id))
+            .flat_map(|link| {
+                link.points_to(self)
+                    .iter()
+                    .map(|&node| self.node(node).file_id)
+            })
             .collect()
     }
-    pub(crate) fn problems<'a, 'b>(&'b self, file_id: FileId, root: ast::Root<'a>) -> Vec<(ast::Name<'a>, &'b Problem)> {
+    pub(crate) fn problems<'a, 'b>(
+        &'b self,
+        file_id: FileId,
+        root: ast::Root<'a>,
+    ) -> Vec<(ast::Name<'a>, &'b Problem)> {
         let node = self.file_id2node[&file_id];
         self.node(node)
             .links
@@ -176,7 +177,11 @@ impl Link {
     fn points_to(self, tree: &ModuleTreeDescriptor) -> &[Node] {
         &tree.link(self).points_to
     }
-    pub(crate) fn bind_source<'a>(self, tree: &ModuleTreeDescriptor, root: ast::Root<'a>) -> ast::Module<'a> {
+    pub(crate) fn bind_source<'a>(
+        self,
+        tree: &ModuleTreeDescriptor,
+        root: ast::Root<'a>,
+    ) -> ast::Module<'a> {
         modules(root)
             .filter(|(name, _)| name == &tree.link(self).name)
             .next()
@@ -185,22 +190,21 @@ impl Link {
     }
 }
 
-
 fn resolve_submodule(
     file_id: FileId,
     name: &SmolStr,
-    file_resolver: &FileResolverImp
+    file_resolver: &FileResolverImp,
 ) -> (Vec<FileId>, Option<Problem>) {
     let mod_name = file_resolver.file_stem(file_id);
-    let is_dir_owner =
-        mod_name == "mod" || mod_name == "lib" || mod_name == "main";
+    let is_dir_owner = mod_name == "mod" || mod_name == "lib" || mod_name == "main";
 
     let file_mod = RelativePathBuf::from(format!("../{}.rs", name));
     let dir_mod = RelativePathBuf::from(format!("../{}/mod.rs", name));
     let points_to: Vec<FileId>;
     let problem: Option<Problem>;
     if is_dir_owner {
-        points_to = [&file_mod, &dir_mod].iter()
+        points_to = [&file_mod, &dir_mod]
+            .iter()
             .filter_map(|path| file_resolver.resolve(file_id, path))
             .collect();
         problem = if points_to.is_empty() {
@@ -223,7 +227,7 @@ fn resolve_submodule(
 #[derive(Debug, Clone)]
 pub struct FnDescriptor {
     pub name: String,
-    pub label : String,
+    pub label: String,
     pub ret_type: Option<String>,
     pub params: Vec<String>,
 }
@@ -233,9 +237,11 @@ impl FnDescriptor {
         let name = node.name()?.text().to_string();
 
         // Strip the body out for the label.
-        let label : String = if let Some(body) = node.body() {
+        let label: String = if let Some(body) = node.body() {
             let body_range = body.syntax().range();
-            let label : String = node.syntax().children()
+            let label: String = node
+                .syntax()
+                .children()
                 .filter(|child| !is_subrange(body_range, child.range()))
                 .map(|node| node.text().to_string())
                 .collect();
@@ -251,7 +257,7 @@ impl FnDescriptor {
             name,
             ret_type,
             params,
-            label
+            label,
         })
     }
 
@@ -264,9 +270,11 @@ impl FnDescriptor {
 
             // Maybe use param.pat here? See if we can just extract the name?
             //res.extend(param_list.params().map(|p| p.syntax().text().to_string()));
-            res.extend(param_list.params()
-                .filter_map(|p| p.pat())
-                .map(|pat| pat.syntax().text().to_string())
+            res.extend(
+                param_list
+                    .params()
+                    .filter_map(|p| p.pat())
+                    .map(|pat| pat.syntax().text().to_string()),
             );
         }
         res
diff --git a/crates/ra_analysis/src/imp.rs b/crates/ra_analysis/src/imp.rs
index 5efcaeca0..f1403cb5d 100644
--- a/crates/ra_analysis/src/imp.rs
+++ b/crates/ra_analysis/src/imp.rs
@@ -1,32 +1,31 @@
 use std::{
-    sync::{
-        Arc,
-    },
-    hash::{Hash, Hasher},
-    fmt,
     collections::VecDeque,
+    fmt,
+    hash::{Hash, Hasher},
     iter,
+    sync::Arc,
 };
 
-use relative_path::RelativePath;
-use rustc_hash::FxHashSet;
-use ra_editor::{self, FileSymbol, LineIndex, find_node_at_offset, LocalEdit, resolve_local_name};
+use ra_editor::{self, find_node_at_offset, resolve_local_name, FileSymbol, LineIndex, LocalEdit};
 use ra_syntax::{
-    TextUnit, TextRange, SmolStr, File, AstNode, SyntaxNodeRef,
+    ast::{self, ArgListOwner, Expr, NameOwner},
+    AstNode, File, SmolStr,
     SyntaxKind::*,
-    ast::{self, NameOwner, ArgListOwner, Expr},
+    SyntaxNodeRef, TextRange, TextUnit,
 };
+use relative_path::RelativePath;
+use rustc_hash::FxHashSet;
 
 use crate::{
-    FileId, FileResolver, Query, Diagnostic, SourceChange, SourceFileEdit, Position, FileSystemEdit,
-    JobToken, CrateGraph, CrateId,
-    roots::{SourceRoot, ReadonlySourceRoot, WritableSourceRoot},
     descriptors::{FnDescriptor, ModuleTreeDescriptor, Problem},
+    roots::{ReadonlySourceRoot, SourceRoot, WritableSourceRoot},
+    CrateGraph, CrateId, Diagnostic, FileId, FileResolver, FileSystemEdit, JobToken, Position,
+    Query, SourceChange, SourceFileEdit,
 };
 
 #[derive(Clone, Debug)]
 pub(crate) struct FileResolverImp {
-    inner: Arc<FileResolver>
+    inner: Arc<FileResolver>,
 }
 
 impl PartialEq for FileResolverImp {
@@ -35,8 +34,7 @@ impl PartialEq for FileResolverImp {
     }
 }
 
-impl Eq for FileResolverImp {
-}
+impl Eq for FileResolverImp {}
 
 impl Hash for FileResolverImp {
     fn hash<H: Hasher>(&self, hasher: &mut H) {
@@ -67,17 +65,23 @@ impl Default for FileResolverImp {
             fn file_stem(&self, _file_: FileId) -> String {
                 panic!("file resolver not set")
             }
-            fn resolve(&self, _file_id: FileId, _path: &::relative_path::RelativePath) -> Option<FileId> {
+            fn resolve(
+                &self,
+                _file_id: FileId,
+                _path: &::relative_path::RelativePath,
+            ) -> Option<FileId> {
                 panic!("file resolver not set")
             }
         }
-        FileResolverImp { inner: Arc::new(DummyResolver) }
+        FileResolverImp {
+            inner: Arc::new(DummyResolver),
+        }
     }
 }
 
 #[derive(Debug)]
 pub(crate) struct AnalysisHostImpl {
-    data: WorldData
+    data: WorldData,
 }
 
 impl AnalysisHostImpl {
@@ -91,13 +95,13 @@ impl AnalysisHostImpl {
             data: self.data.clone(),
         }
     }
-    pub fn change_files(&mut self, changes: &mut dyn Iterator<Item=(FileId, Option<String>)>) {
-        self.data_mut()
-            .root.apply_changes(changes, None);
+    pub fn change_files(&mut self, changes: &mut dyn Iterator<Item = (FileId, Option<String>)>) {
+        self.data_mut().root.apply_changes(changes, None);
     }
     pub fn set_file_resolver(&mut self, resolver: FileResolverImp) {
         self.data_mut()
-            .root.apply_changes(&mut iter::empty(), Some(resolver));
+            .root
+            .apply_changes(&mut iter::empty(), Some(resolver));
     }
     pub fn set_crate_graph(&mut self, graph: CrateGraph) {
         let mut visited = FxHashSet::default();
@@ -131,7 +135,12 @@ impl AnalysisImpl {
         if self.data.root.contains(file_id) {
             return &self.data.root;
         }
-        &**self.data.libs.iter().find(|it| it.contains(file_id)).unwrap()
+        &**self
+            .data
+            .libs
+            .iter()
+            .find(|it| it.contains(file_id))
+            .unwrap()
     }
     pub fn file_syntax(&self, file_id: FileId) -> File {
         self.root(file_id).syntax(file_id)
@@ -142,18 +151,17 @@ impl AnalysisImpl {
     pub fn world_symbols(&self, query: Query, token: &JobToken) -> Vec<(FileId, FileSymbol)> {
         let mut buf = Vec::new();
         if query.libs {
-            self.data.libs.iter()
-                .for_each(|it| it.symbols(&mut buf));
+            self.data.libs.iter().for_each(|it| it.symbols(&mut buf));
         } else {
             self.data.root.symbols(&mut buf);
         }
         query.search(&buf, token)
-
     }
     pub fn parent_module(&self, file_id: FileId) -> Vec<(FileId, FileSymbol)> {
         let root = self.root(file_id);
         let module_tree = root.module_tree();
-        module_tree.parent_modules(file_id)
+        module_tree
+            .parent_modules(file_id)
             .iter()
             .map(|link| {
                 let file_id = link.owner(&module_tree);
@@ -203,15 +211,17 @@ impl AnalysisImpl {
         let file = root.syntax(file_id);
         let syntax = file.syntax();
         if let Some(name_ref) = find_node_at_offset::<ast::NameRef>(syntax, offset) {
-
             // First try to resolve the symbol locally
             if let Some((name, range)) = resolve_local_name(&file, offset, name_ref) {
                 let mut vec = vec![];
-                vec.push((file_id, FileSymbol {
-                    name,
-                    node_range: range,
-                    kind : NAME
-                }));
+                vec.push((
+                    file_id,
+                    FileSymbol {
+                        name,
+                        node_range: range,
+                        kind: NAME,
+                    },
+                ));
 
                 return vec;
             } else {
@@ -224,17 +234,21 @@ impl AnalysisImpl {
                 if module.has_semi() {
                     let file_ids = self.resolve_module(&*module_tree, file_id, module);
 
-                    let res = file_ids.into_iter().map(|id| {
-                        let name = module.name()
-                            .map(|n| n.text())
-                            .unwrap_or_else(|| SmolStr::new(""));
-                        let symbol = FileSymbol {
-                            name,
-                            node_range: TextRange::offset_len(0.into(), 0.into()),
-                            kind: MODULE,
-                        };
-                        (id, symbol)
-                    }).collect();
+                    let res = file_ids
+                        .into_iter()
+                        .map(|id| {
+                            let name = module
+                                .name()
+                                .map(|n| n.text())
+                                .unwrap_or_else(|| SmolStr::new(""));
+                            let symbol = FileSymbol {
+                                name,
+                                node_range: TextRange::offset_len(0.into(), 0.into()),
+                                kind: MODULE,
+                            };
+                            (id, symbol)
+                        })
+                        .collect();
 
                     return res;
                 }
@@ -245,12 +259,16 @@ impl AnalysisImpl {
 
     pub fn diagnostics(&self, file_id: FileId) -> Vec<Diagnostic> {
         let root = self.root(file_id);
-        let module_tree  = root.module_tree();
+        let module_tree = root.module_tree();
         let syntax = root.syntax(file_id);
 
         let mut res = ra_editor::diagnostics(&syntax)
             .into_iter()
-            .map(|d| Diagnostic { range: d.range, message: d.msg, fix: None })
+            .map(|d| Diagnostic {
+                range: d.range,
+                message: d.msg,
+                fix: None,
+            })
             .collect::<Vec<_>>();
 
         for (name_node, problem) in module_tree.problems(file_id, syntax.ast()) {
@@ -273,8 +291,14 @@ impl AnalysisImpl {
                     }
                 }
                 Problem::NotDirOwner { move_to, candidate } => {
-                    let move_file = FileSystemEdit::MoveFile { file: file_id, path: move_to.clone() };
-                    let create_file = FileSystemEdit::CreateFile { anchor: file_id, path: move_to.join(candidate) };
+                    let move_file = FileSystemEdit::MoveFile {
+                        file: file_id,
+                        path: move_to.clone(),
+                    };
+                    let create_file = FileSystemEdit::CreateFile {
+                        anchor: file_id,
+                        path: move_to.join(candidate),
+                    };
                     let fix = SourceChange {
                         label: "move file and create module".to_string(),
                         source_file_edits: Vec::new(),
@@ -297,23 +321,34 @@ impl AnalysisImpl {
         let file = self.file_syntax(file_id);
         let offset = range.start();
         let actions = vec![
-            ("flip comma", ra_editor::flip_comma(&file, offset).map(|f| f())),
-            ("add `#[derive]`", ra_editor::add_derive(&file, offset).map(|f| f())),
+            (
+                "flip comma",
+                ra_editor::flip_comma(&file, offset).map(|f| f()),
+            ),
+            (
+                "add `#[derive]`",
+                ra_editor::add_derive(&file, offset).map(|f| f()),
+            ),
             ("add impl", ra_editor::add_impl(&file, offset).map(|f| f())),
-            ("introduce variable", ra_editor::introduce_variable(&file, range).map(|f| f())),
+            (
+                "introduce variable",
+                ra_editor::introduce_variable(&file, range).map(|f| f()),
+            ),
         ];
-        actions.into_iter()
+        actions
+            .into_iter()
             .filter_map(|(name, local_edit)| {
-                Some(SourceChange::from_local_edit(
-                    file_id, name, local_edit?,
-                ))
+                Some(SourceChange::from_local_edit(file_id, name, local_edit?))
             })
             .collect()
     }
 
-    pub fn resolve_callable(&self, file_id: FileId, offset: TextUnit, token: &JobToken)
-        -> Option<(FnDescriptor, Option<usize>)> {
-
+    pub fn resolve_callable(
+        &self,
+        file_id: FileId,
+        offset: TextUnit,
+        token: &JobToken,
+    ) -> Option<(FnDescriptor, Option<usize>)> {
         let root = self.root(file_id);
         let file = root.syntax(file_id);
         let syntax = file.syntax();
@@ -332,9 +367,7 @@ impl AnalysisImpl {
                         let mut current_parameter = None;
 
                         let num_params = descriptor.params.len();
-                        let has_self = fn_def.param_list()
-                            .and_then(|l| l.self_param())
-                            .is_some();
+                        let has_self = fn_def.param_list().and_then(|l| l.self_param()).is_some();
 
                         if num_params == 1 {
                             if !has_self {
@@ -350,8 +383,11 @@ impl AnalysisImpl {
                                 let start = arg_list.syntax().range().start();
 
                                 let range_search = TextRange::from_to(start, offset);
-                                let mut commas: usize = arg_list.syntax().text()
-                                    .slice(range_search).to_string()
+                                let mut commas: usize = arg_list
+                                    .syntax()
+                                    .text()
+                                    .slice(range_search)
+                                    .to_string()
                                     .matches(",")
                                     .count();
 
@@ -381,7 +417,12 @@ impl AnalysisImpl {
         self.world_symbols(query, token)
     }
 
-    fn resolve_module(&self, module_tree: &ModuleTreeDescriptor, file_id: FileId, module: ast::Module) -> Vec<FileId> {
+    fn resolve_module(
+        &self,
+        module_tree: &ModuleTreeDescriptor,
+        file_id: FileId,
+        module: ast::Module,
+    ) -> Vec<FileId> {
         let name = match module.name() {
             Some(name) => name.text(),
             None => return Vec::new(),
@@ -407,15 +448,17 @@ impl SourceChange {
             label: label.to_string(),
             source_file_edits: vec![file_edit],
             file_system_edits: vec![],
-            cursor_position: edit.cursor_position
-                .map(|offset| Position { offset, file_id })
+            cursor_position: edit
+                .cursor_position
+                .map(|offset| Position { offset, file_id }),
         }
     }
 }
 
 impl CrateGraph {
     fn crate_id_for_crate_root(&self, file_id: FileId) -> Option<CrateId> {
-        let (&crate_id, _) = self.crate_roots
+        let (&crate_id, _) = self
+            .crate_roots
             .iter()
             .find(|(_crate_id, &root_id)| root_id == file_id)?;
         Some(crate_id)
@@ -424,7 +467,7 @@ impl CrateGraph {
 
 enum FnCallNode<'a> {
     CallExpr(ast::CallExpr<'a>),
-    MethodCallExpr(ast::MethodCallExpr<'a>)
+    MethodCallExpr(ast::MethodCallExpr<'a>),
 }
 
 impl<'a> FnCallNode<'a> {
@@ -440,27 +483,23 @@ impl<'a> FnCallNode<'a> {
 
     pub fn name_ref(&self) -> Option<ast::NameRef> {
         match *self {
-            FnCallNode::CallExpr(call_expr) => {
-                Some(match call_expr.expr()? {
-                    Expr::PathExpr(path_expr) => {
-                        path_expr.path()?.segment()?.name_ref()?
-                    },
-                    _ => return None
-                })
-            },
-
-            FnCallNode::MethodCallExpr(call_expr) => {
-                call_expr.syntax().children()
-                    .filter_map(ast::NameRef::cast)
-                    .nth(0)
-            }
+            FnCallNode::CallExpr(call_expr) => Some(match call_expr.expr()? {
+                Expr::PathExpr(path_expr) => path_expr.path()?.segment()?.name_ref()?,
+                _ => return None,
+            }),
+
+            FnCallNode::MethodCallExpr(call_expr) => call_expr
+                .syntax()
+                .children()
+                .filter_map(ast::NameRef::cast)
+                .nth(0),
         }
     }
 
     pub fn arg_list(&self) -> Option<ast::ArgList> {
         match *self {
             FnCallNode::CallExpr(expr) => expr.arg_list(),
-            FnCallNode::MethodCallExpr(expr) => expr.arg_list()
+            FnCallNode::MethodCallExpr(expr) => expr.arg_list(),
         }
     }
 }
diff --git a/crates/ra_analysis/src/job.rs b/crates/ra_analysis/src/job.rs
index ea1652a26..2871f9839 100644
--- a/crates/ra_analysis/src/job.rs
+++ b/crates/ra_analysis/src/job.rs
@@ -14,15 +14,20 @@ impl JobHandle {
     pub fn new() -> (JobHandle, JobToken) {
         let (sender_alive, receiver_alive) = bounded(0);
         let (sender_canceled, receiver_canceled) = bounded(0);
-        let token = JobToken { _job_alive: sender_alive, job_canceled: receiver_canceled };
-        let handle = JobHandle { job_alive: receiver_alive, _job_canceled: sender_canceled };
+        let token = JobToken {
+            _job_alive: sender_alive,
+            job_canceled: receiver_canceled,
+        };
+        let handle = JobHandle {
+            job_alive: receiver_alive,
+            _job_canceled: sender_canceled,
+        };
         (handle, token)
     }
     pub fn has_completed(&self) -> bool {
         is_closed(&self.job_alive)
     }
-    pub fn cancel(self) {
-    }
+    pub fn cancel(self) {}
 }
 
 impl JobToken {
@@ -31,7 +36,6 @@ impl JobToken {
     }
 }
 
-
 // We don't actually send messages through the channels,
 // and instead just check if the channel is closed,
 // so we use uninhabited enum as a message type
diff --git a/crates/ra_analysis/src/lib.rs b/crates/ra_analysis/src/lib.rs
index d8b355a81..2eeacaabe 100644
--- a/crates/ra_analysis/src/lib.rs
+++ b/crates/ra_analysis/src/lib.rs
@@ -1,44 +1,40 @@
 extern crate parking_lot;
 #[macro_use]
 extern crate log;
+extern crate fst;
 extern crate once_cell;
-extern crate ra_syntax;
 extern crate ra_editor;
-extern crate fst;
+extern crate ra_syntax;
 extern crate rayon;
 extern crate relative_path;
 #[macro_use]
 extern crate crossbeam_channel;
 extern crate im;
-extern crate salsa;
 extern crate rustc_hash;
+extern crate salsa;
 
-mod symbol_index;
-mod module_map;
+mod db;
+mod descriptors;
 mod imp;
 mod job;
+mod module_map;
 mod roots;
-mod db;
-mod descriptors;
+mod symbol_index;
 
-use std::{
-    sync::Arc,
-    fmt::Debug,
-};
+use std::{fmt::Debug, sync::Arc};
 
+use crate::imp::{AnalysisHostImpl, AnalysisImpl, FileResolverImp};
+use ra_syntax::{AtomEdit, File, TextRange, TextUnit};
 use relative_path::{RelativePath, RelativePathBuf};
-use ra_syntax::{File, TextRange, TextUnit, AtomEdit};
 use rustc_hash::FxHashMap;
-use crate::imp::{AnalysisImpl, AnalysisHostImpl, FileResolverImp};
 
-pub use ra_editor::{
-    StructureNode, LineIndex, FileSymbol,
-    Runnable, RunnableKind, HighlightedRange, CompletionItem,
-    Fold, FoldKind
-};
 pub use crate::{
-    job::{JobToken, JobHandle},
     descriptors::FnDescriptor,
+    job::{JobHandle, JobToken},
+};
+pub use ra_editor::{
+    CompletionItem, FileSymbol, Fold, FoldKind, HighlightedRange, LineIndex, Runnable,
+    RunnableKind, StructureNode,
 };
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
@@ -59,20 +55,24 @@ pub trait FileResolver: Debug + Send + Sync + 'static {
 
 #[derive(Debug)]
 pub struct AnalysisHost {
-    imp: AnalysisHostImpl
+    imp: AnalysisHostImpl,
 }
 
 impl AnalysisHost {
     pub fn new() -> AnalysisHost {
-        AnalysisHost { imp: AnalysisHostImpl::new() }
+        AnalysisHost {
+            imp: AnalysisHostImpl::new(),
+        }
     }
     pub fn analysis(&self) -> Analysis {
-        Analysis { imp: self.imp.analysis() }
+        Analysis {
+            imp: self.imp.analysis(),
+        }
     }
     pub fn change_file(&mut self, file_id: FileId, text: Option<String>) {
         self.change_files(::std::iter::once((file_id, text)));
     }
-    pub fn change_files(&mut self, mut changes: impl Iterator<Item=(FileId, Option<String>)>) {
+    pub fn change_files(&mut self, mut changes: impl Iterator<Item = (FileId, Option<String>)>) {
         self.imp.change_files(&mut changes)
     }
     pub fn set_file_resolver(&mut self, resolver: Arc<FileResolver>) {
@@ -115,7 +115,7 @@ pub enum FileSystemEdit {
     MoveFile {
         file: FileId,
         path: RelativePathBuf,
-    }
+    },
 }
 
 #[derive(Debug)]
@@ -144,7 +144,7 @@ impl Query {
             only_types: false,
             libs: false,
             exact: false,
-            limit: usize::max_value()
+            limit: usize::max_value(),
         }
     }
     pub fn only_types(&mut self) {
@@ -163,7 +163,7 @@ impl Query {
 
 #[derive(Debug)]
 pub struct Analysis {
-    imp: AnalysisImpl
+    imp: AnalysisImpl,
 }
 
 impl Analysis {
@@ -195,7 +195,11 @@ impl Analysis {
     }
     pub fn on_eq_typed(&self, file_id: FileId, offset: TextUnit) -> Option<SourceChange> {
         let file = self.imp.file_syntax(file_id);
-        Some(SourceChange::from_local_edit(file_id, "add semicolon", ra_editor::on_eq_typed(&file, offset)?))
+        Some(SourceChange::from_local_edit(
+            file_id,
+            "add semicolon",
+            ra_editor::on_eq_typed(&file, offset)?,
+        ))
     }
     pub fn file_structure(&self, file_id: FileId) -> Vec<StructureNode> {
         let file = self.imp.file_syntax(file_id);
@@ -204,8 +208,14 @@ impl Analysis {
     pub fn symbol_search(&self, query: Query, token: &JobToken) -> Vec<(FileId, FileSymbol)> {
         self.imp.world_symbols(query, token)
     }
-    pub fn approximately_resolve_symbol(&self, file_id: FileId, offset: TextUnit, token: &JobToken) -> Vec<(FileId, FileSymbol)> {
-        self.imp.approximately_resolve_symbol(file_id, offset, token)
+    pub fn approximately_resolve_symbol(
+        &self,
+        file_id: FileId,
+        offset: TextUnit,
+        token: &JobToken,
+    ) -> Vec<(FileId, FileSymbol)> {
+        self.imp
+            .approximately_resolve_symbol(file_id, offset, token)
     }
     pub fn parent_module(&self, file_id: FileId) -> Vec<(FileId, FileSymbol)> {
         self.imp.parent_module(file_id)
@@ -239,15 +249,19 @@ impl Analysis {
         ra_editor::folding_ranges(&file)
     }
 
-    pub fn resolve_callable(&self, file_id: FileId, offset: TextUnit, token: &JobToken)
-        -> Option<(FnDescriptor, Option<usize>)> {
+    pub fn resolve_callable(
+        &self,
+        file_id: FileId,
+        offset: TextUnit,
+        token: &JobToken,
+    ) -> Option<(FnDescriptor, Option<usize>)> {
         self.imp.resolve_callable(file_id, offset, token)
     }
 }
 
 #[derive(Debug)]
 pub struct LibraryData {
-    root: roots::ReadonlySourceRoot
+    root: roots::ReadonlySourceRoot,
 }
 
 impl LibraryData {
diff --git a/crates/ra_analysis/src/module_map.rs b/crates/ra_analysis/src/module_map.rs
index c1799e3d4..ff0ec3cc7 100644
--- a/crates/ra_analysis/src/module_map.rs
+++ b/crates/ra_analysis/src/module_map.rs
@@ -1,10 +1,11 @@
-use std::sync::Arc;
 use crate::{
-    FileId,
-    db::{SyntaxDatabase},
+    db::SyntaxDatabase,
     descriptors::{ModuleDescriptor, ModuleTreeDescriptor},
+    FileId,
 };
 
+use std::sync::Arc;
+
 salsa::query_group! {
     pub(crate) trait ModulesDatabase: SyntaxDatabase {
         fn module_tree(key: ()) -> Arc<ModuleTreeDescriptor> {
@@ -16,7 +17,6 @@ salsa::query_group! {
     }
 }
 
-
 fn module_descriptor(db: &impl ModulesDatabase, file_id: FileId) -> Arc<ModuleDescriptor> {
     let file = db.file_syntax(file_id);
     Arc::new(ModuleDescriptor::new(file.ast()))
@@ -29,6 +29,9 @@ fn module_tree(db: &impl ModulesDatabase, (): ()) -> Arc<ModuleTreeDescriptor> {
         let module_descr = db.module_descriptor(file_id);
         files.push((file_id, module_descr));
     }
-    let res = ModuleTreeDescriptor::new(files.iter().map(|(file_id, descr)| (*file_id, &**descr)), &file_set.resolver);
+    let res = ModuleTreeDescriptor::new(
+        files.iter().map(|(file_id, descr)| (*file_id, &**descr)),
+        &file_set.resolver,
+    );
     Arc::new(res)
 }
diff --git a/crates/ra_analysis/src/roots.rs b/crates/ra_analysis/src/roots.rs
index 76bcecd38..1f2b21b27 100644
--- a/crates/ra_analysis/src/roots.rs
+++ b/crates/ra_analysis/src/roots.rs
@@ -1,22 +1,19 @@
-use std::{
-    sync::Arc,
-    panic,
-};
+use std::{panic, sync::Arc};
 
 use once_cell::sync::OnceCell;
-use rayon::prelude::*;
-use salsa::Database;
-use rustc_hash::{FxHashMap, FxHashSet};
 use ra_editor::LineIndex;
 use ra_syntax::File;
+use rayon::prelude::*;
+use rustc_hash::{FxHashMap, FxHashSet};
+use salsa::Database;
 
 use crate::{
-    FileId,
-    imp::FileResolverImp,
-    symbol_index::SymbolIndex,
-    descriptors::{ModuleDescriptor, ModuleTreeDescriptor},
     db::{self, FilesDatabase, SyntaxDatabase},
+    descriptors::{ModuleDescriptor, ModuleTreeDescriptor},
+    imp::FileResolverImp,
     module_map::ModulesDatabase,
+    symbol_index::SymbolIndex,
+    FileId,
 };
 
 pub(crate) trait SourceRoot {
@@ -35,7 +32,7 @@ pub(crate) struct WritableSourceRoot {
 impl WritableSourceRoot {
     pub fn apply_changes(
         &mut self,
-        changes: &mut dyn Iterator<Item=(FileId, Option<String>)>,
+        changes: &mut dyn Iterator<Item = (FileId, Option<String>)>,
         file_resolver: Option<FileResolverImp>,
     ) {
         let mut changed = FxHashSet::default();
@@ -46,22 +43,22 @@ impl WritableSourceRoot {
                     removed.insert(file_id);
                 }
                 Some(text) => {
-                    self.db.query(db::FileTextQuery)
+                    self.db
+                        .query(db::FileTextQuery)
                         .set(file_id, Arc::new(text));
                     changed.insert(file_id);
                 }
             }
         }
         let file_set = self.db.file_set(());
-        let mut files: FxHashSet<FileId> = file_set
-            .files
-            .clone();
+        let mut files: FxHashSet<FileId> = file_set.files.clone();
         for file_id in removed {
             files.remove(&file_id);
         }
         files.extend(changed);
         let resolver = file_resolver.unwrap_or_else(|| file_set.resolver.clone());
-        self.db.query(db::FileSetQuery)
+        self.db
+            .query(db::FileSetQuery)
             .set((), Arc::new(db::FileSet { files, resolver }));
     }
 }
@@ -71,9 +68,7 @@ impl SourceRoot for WritableSourceRoot {
         self.db.module_tree(())
     }
     fn contains(&self, file_id: FileId) -> bool {
-        self.db.file_set(())
-            .files
-            .contains(&file_id)
+        self.db.file_set(()).files.contains(&file_id)
     }
     fn lines(&self, file_id: FileId) -> Arc<LineIndex> {
         self.db.file_lines(file_id)
@@ -83,7 +78,7 @@ impl SourceRoot for WritableSourceRoot {
     }
     fn symbols<'a>(&'a self, acc: &mut Vec<Arc<SymbolIndex>>) {
         let db = &self.db;
-        let symbols =  db.file_set(());
+        let symbols = db.file_set(());
         let symbols = symbols
             .files
             .iter()
@@ -108,12 +103,15 @@ impl FileData {
         }
     }
     fn lines(&self) -> &Arc<LineIndex> {
-        self.lines.get_or_init(|| Arc::new(LineIndex::new(&self.text)))
+        self.lines
+            .get_or_init(|| Arc::new(LineIndex::new(&self.text)))
     }
     fn syntax(&self) -> &File {
         let text = &self.text;
         let syntax = &self.syntax;
-        match panic::catch_unwind(panic::AssertUnwindSafe(|| syntax.get_or_init(|| File::parse(text)))) {
+        match panic::catch_unwind(panic::AssertUnwindSafe(|| {
+            syntax.get_or_init(|| File::parse(text))
+        })) {
             Ok(file) => file,
             Err(err) => {
                 error!("Parser paniced on:\n------\n{}\n------\n", text);
@@ -131,22 +129,23 @@ pub(crate) struct ReadonlySourceRoot {
 }
 
 impl ReadonlySourceRoot {
-    pub(crate) fn new(files: Vec<(FileId, String)>, file_resolver: FileResolverImp) -> ReadonlySourceRoot {
-        let modules = files.par_iter()
+    pub(crate) fn new(
+        files: Vec<(FileId, String)>,
+        file_resolver: FileResolverImp,
+    ) -> ReadonlySourceRoot {
+        let modules = files
+            .par_iter()
             .map(|(file_id, text)| {
                 let syntax = File::parse(text);
                 let mod_descr = ModuleDescriptor::new(syntax.ast());
                 (*file_id, syntax, mod_descr)
             })
             .collect::<Vec<_>>();
-        let module_tree = ModuleTreeDescriptor::new(
-            modules.iter().map(|it| (it.0, &it.2)),
-            &file_resolver,
-        );
+        let module_tree =
+            ModuleTreeDescriptor::new(modules.iter().map(|it| (it.0, &it.2)), &file_resolver);
 
-        let symbol_index = SymbolIndex::for_files(
-            modules.par_iter().map(|it| (it.0, it.1.clone()))
-        );
+        let symbol_index =
+            SymbolIndex::for_files(modules.par_iter().map(|it| (it.0, it.1.clone())));
         let file_map: FxHashMap<FileId, FileData> = files
             .into_iter()
             .map(|(id, text)| (id, FileData::new(text)))
diff --git a/crates/ra_analysis/src/symbol_index.rs b/crates/ra_analysis/src/symbol_index.rs
index 54672fde4..51eef8170 100644
--- a/crates/ra_analysis/src/symbol_index.rs
+++ b/crates/ra_analysis/src/symbol_index.rs
@@ -1,15 +1,16 @@
-use std::{
-    sync::Arc,
-    hash::{Hash, Hasher},
-};
-use ra_editor::{FileSymbol, file_symbols};
+use crate::{FileId, JobToken, Query};
+use fst::{self, Streamer};
+use ra_editor::{file_symbols, FileSymbol};
 use ra_syntax::{
     File,
     SyntaxKind::{self, *},
 };
-use fst::{self, Streamer};
 use rayon::prelude::*;
-use crate::{Query, FileId, JobToken};
+
+use std::{
+    hash::{Hash, Hasher},
+    sync::Arc,
+};
 
 #[derive(Debug)]
 pub(crate) struct SymbolIndex {
@@ -23,8 +24,7 @@ impl PartialEq for SymbolIndex {
     }
 }
 
-impl Eq for SymbolIndex {
-}
+impl Eq for SymbolIndex {}
 
 impl Hash for SymbolIndex {
     fn hash<H: Hasher>(&self, hasher: &mut H) {
@@ -33,14 +33,12 @@ impl Hash for SymbolIndex {
 }
 
 impl SymbolIndex {
-    pub(crate) fn for_files(files: impl ParallelIterator<Item=(FileId, File)>) -> SymbolIndex {
+    pub(crate) fn for_files(files: impl ParallelIterator<Item = (FileId, File)>) -> SymbolIndex {
         let mut symbols = files
             .flat_map(|(file_id, file)| {
                 file_symbols(&file)
                     .into_iter()
-                    .map(move |symbol| {
-                        (symbol.name.as_str().to_lowercase(), (file_id, symbol))
-                    })
+                    .map(move |symbol| (symbol.name.as_str().to_lowercase(), (file_id, symbol)))
                     .collect::<Vec<_>>()
             })
             .collect::<Vec<_>>();
@@ -48,9 +46,7 @@ impl SymbolIndex {
         symbols.dedup_by(|s1, s2| s1.0 == s2.0);
         let (names, symbols): (Vec<String>, Vec<(FileId, FileSymbol)>) =
             symbols.into_iter().unzip();
-        let map = fst::Map::from_iter(
-            names.into_iter().zip(0u64..)
-        ).unwrap();
+        let map = fst::Map::from_iter(names.into_iter().zip(0u64..)).unwrap();
         SymbolIndex { symbols, map }
     }
 
@@ -65,7 +61,6 @@ impl Query {
         indices: &[Arc<SymbolIndex>],
         token: &JobToken,
     ) -> Vec<(FileId, FileSymbol)> {
-
         let mut op = fst::map::OpBuilder::new();
         for file_symbols in indices.iter() {
             let automaton = fst::automaton::Subsequence::new(&self.lowercased);
diff --git a/crates/ra_analysis/tests/tests.rs b/crates/ra_analysis/tests/tests.rs
index 2d3679fa9..e0c637d65 100644
--- a/crates/ra_analysis/tests/tests.rs
+++ b/crates/ra_analysis/tests/tests.rs
@@ -1,32 +1,31 @@
-extern crate relative_path;
 extern crate ra_analysis;
-extern crate rustc_hash;
 extern crate ra_editor;
 extern crate ra_syntax;
+extern crate relative_path;
+extern crate rustc_hash;
 extern crate test_utils;
 
-use std::{
-    sync::Arc,
-};
+use std::sync::Arc;
 
-use rustc_hash::FxHashMap;
+use ra_analysis::{
+    Analysis, AnalysisHost, CrateGraph, CrateId, FileId, FileResolver, FnDescriptor, JobHandle,
+};
 use relative_path::{RelativePath, RelativePathBuf};
-use ra_analysis::{Analysis, AnalysisHost, FileId, FileResolver, JobHandle, CrateGraph, CrateId, FnDescriptor};
+use rustc_hash::FxHashMap;
 use test_utils::{assert_eq_dbg, extract_offset};
 
 #[derive(Debug)]
 struct FileMap(Vec<(FileId, RelativePathBuf)>);
 
 impl FileMap {
-    fn iter<'a>(&'a self) -> impl Iterator<Item=(FileId, &'a RelativePath)> + 'a {
-        self.0.iter().map(|(id, path)| (*id, path.as_relative_path()))
+    fn iter<'a>(&'a self) -> impl Iterator<Item = (FileId, &'a RelativePath)> + 'a {
+        self.0
+            .iter()
+            .map(|(id, path)| (*id, path.as_relative_path()))
     }
 
     fn path(&self, id: FileId) -> &RelativePath {
-        self.iter()
-            .find(|&(it, _)| it == id)
-            .unwrap()
-            .1
+        self.iter().find(|&(it, _)| it == id).unwrap().1
     }
 }
 
@@ -71,10 +70,7 @@ fn get_signature(text: &str) -> (FnDescriptor, Option<usize>) {
 
 #[test]
 fn test_resolve_module() {
-    let snap = analysis(&[
-        ("/lib.rs", "mod foo;"),
-        ("/foo.rs", "")
-    ]);
+    let snap = analysis(&[("/lib.rs", "mod foo;"), ("/foo.rs", "")]);
     let (_handle, token) = JobHandle::new();
     let symbols = snap.approximately_resolve_symbol(FileId(1), 4.into(), &token);
     assert_eq_dbg(
@@ -82,10 +78,7 @@ fn test_resolve_module() {
         &symbols,
     );
 
-    let snap = analysis(&[
-        ("/lib.rs", "mod foo;"),
-        ("/foo/mod.rs", "")
-    ]);
+    let snap = analysis(&[("/lib.rs", "mod foo;"), ("/foo/mod.rs", "")]);
     let symbols = snap.approximately_resolve_symbol(FileId(1), 4.into(), &token);
     assert_eq_dbg(
         r#"[(FileId(2), FileSymbol { name: "foo", node_range: [0; 0), kind: MODULE })]"#,
@@ -114,18 +107,12 @@ fn test_unresolved_module_diagnostic() {
 fn test_unresolved_module_diagnostic_no_diag_for_inline_mode() {
     let snap = analysis(&[("/lib.rs", "mod foo {}")]);
     let diagnostics = snap.diagnostics(FileId(1));
-    assert_eq_dbg(
-        r#"[]"#,
-        &diagnostics,
-    );
+    assert_eq_dbg(r#"[]"#, &diagnostics);
 }
 
 #[test]
 fn test_resolve_parent_module() {
-    let snap = analysis(&[
-        ("/lib.rs", "mod foo;"),
-        ("/foo.rs", ""),
-    ]);
+    let snap = analysis(&[("/lib.rs", "mod foo;"), ("/foo.rs", "")]);
     let symbols = snap.parent_module(FileId(2));
     assert_eq_dbg(
         r#"[(FileId(1), FileSymbol { name: "foo", node_range: [0; 8), kind: MODULE })]"#,
@@ -135,10 +122,7 @@ fn test_resolve_parent_module() {
 
 #[test]
 fn test_resolve_crate_root() {
-    let mut host = analysis_host(&[
-        ("/lib.rs", "mod foo;"),
-        ("/foo.rs", ""),
-    ]);
+    let mut host = analysis_host(&[("/lib.rs", "mod foo;"), ("/foo.rs", "")]);
     let snap = host.analysis();
     assert!(snap.crate_for(FileId(2)).is_empty());
 
@@ -152,20 +136,18 @@ fn test_resolve_crate_root() {
     host.set_crate_graph(crate_graph);
     let snap = host.analysis();
 
-    assert_eq!(
-        snap.crate_for(FileId(2)),
-        vec![CrateId(1)],
-    );
+    assert_eq!(snap.crate_for(FileId(2)), vec![CrateId(1)],);
 }
 
 #[test]
 fn test_fn_signature_two_args_first() {
     let (desc, param) = get_signature(
-r#"fn foo(x: u32, y: u32) -> u32 {x + y}
-fn bar() { foo(<|>3, ); }"#);
+        r#"fn foo(x: u32, y: u32) -> u32 {x + y}
+fn bar() { foo(<|>3, ); }"#,
+    );
 
     assert_eq!(desc.name, "foo".to_string());
-    assert_eq!(desc.params, vec!("x".to_string(),"y".to_string()));
+    assert_eq!(desc.params, vec!("x".to_string(), "y".to_string()));
     assert_eq!(desc.ret_type, Some("-> u32".into()));
     assert_eq!(param, Some(0));
 }
@@ -174,10 +156,11 @@ fn bar() { foo(<|>3, ); }"#);
 fn test_fn_signature_two_args_second() {
     let (desc, param) = get_signature(
         r#"fn foo(x: u32, y: u32) -> u32 {x + y}
-fn bar() { foo(3, <|>); }"#);
+fn bar() { foo(3, <|>); }"#,
+    );
 
     assert_eq!(desc.name, "foo".to_string());
-    assert_eq!(desc.params, vec!("x".to_string(),"y".to_string()));
+    assert_eq!(desc.params, vec!("x".to_string(), "y".to_string()));
     assert_eq!(desc.ret_type, Some("-> u32".into()));
     assert_eq!(param, Some(1));
 }
@@ -185,8 +168,9 @@ fn bar() { foo(3, <|>); }"#);
 #[test]
 fn test_fn_signature_for_impl() {
     let (desc, param) = get_signature(
-r#"struct F; impl F { pub fn new() { F{}} }
-fn bar() {let _ : F = F::new(<|>);}"#);
+        r#"struct F; impl F { pub fn new() { F{}} }
+fn bar() {let _ : F = F::new(<|>);}"#,
+    );
 
     assert_eq!(desc.name, "new".to_string());
     assert_eq!(desc.params, Vec::<String>::new());
@@ -197,7 +181,7 @@ fn bar() {let _ : F = F::new(<|>);}"#);
 #[test]
 fn test_fn_signature_for_method_self() {
     let (desc, param) = get_signature(
-r#"struct F;
+        r#"struct F;
 impl F {
     pub fn new() -> F{
         F{}
@@ -209,7 +193,8 @@ impl F {
 fn bar() {
     let f : F = F::new();
     f.do_it(<|>);
-}"#);
+}"#,
+    );
 
     assert_eq!(desc.name, "do_it".to_string());
     assert_eq!(desc.params, vec!["&self".to_string()]);
@@ -220,7 +205,7 @@ fn bar() {
 #[test]
 fn test_fn_signature_for_method_with_arg() {
     let (desc, param) = get_signature(
-r#"struct F;
+        r#"struct F;
 impl F {
     pub fn new() -> F{
         F{}
@@ -232,7 +217,8 @@ impl F {
 fn bar() {
     let f : F = F::new();
     f.do_it(<|>);
-}"#);
+}"#,
+    );
 
     assert_eq!(desc.name, "do_it".to_string());
     assert_eq!(desc.params, vec!["&self".to_string(), "x".to_string()]);