13 files changed, 95 insertions, 56 deletions

diff --git a/crates/ra_assists/src/assists/add_custom_impl.rs b/crates/ra_assists/src/assists/add_custom_impl.rs
index 037306fd6..9b8955710 100644
--- a/crates/ra_assists/src/assists/add_custom_impl.rs
+++ b/crates/ra_assists/src/assists/add_custom_impl.rs
@@ -10,7 +10,7 @@ use ra_syntax::{
     TextRange, TextUnit,
 };
 
-const DERIVE_TRAIT: &'static str = "derive";
+const DERIVE_TRAIT: &str = "derive";
 
 // Assist: add_custom_impl
 //
diff --git a/crates/ra_cargo_watch/src/lib.rs b/crates/ra_cargo_watch/src/lib.rs
index cb0856aa4..20fa5a924 100644
--- a/crates/ra_cargo_watch/src/lib.rs
+++ b/crates/ra_cargo_watch/src/lib.rs
@@ -184,8 +184,13 @@ impl CheckWatcherState {
         workspace_root: PathBuf,
         shared: Arc<RwLock<CheckWatcherSharedState>>,
     ) -> CheckWatcherState {
-        let watcher = WatchThread::new(&options, &workspace_root);
-        CheckWatcherState { options, workspace_root, watcher, last_update_req: None, shared }
+        CheckWatcherState {
+            options,
+            workspace_root,
+            watcher: WatchThread::dummy(),
+            last_update_req: None,
+            shared,
+        }
     }
 
     fn run(&mut self, task_send: &Sender<CheckTask>, cmd_recv: &Receiver<CheckCommand>) {
@@ -313,6 +318,10 @@ enum CheckEvent {
 }
 
 impl WatchThread {
+    fn dummy() -> WatchThread {
+        WatchThread { handle: None, message_recv: never() }
+    }
+
     fn new(options: &CheckOptions, workspace_root: &PathBuf) -> WatchThread {
         let mut args: Vec<String> = vec![
             options.command.clone(),
diff --git a/crates/ra_cli/src/main.rs b/crates/ra_cli/src/main.rs
index 3808590ab..806612c2c 100644
--- a/crates/ra_cli/src/main.rs
+++ b/crates/ra_cli/src/main.rs
@@ -22,7 +22,7 @@ pub enum Verbosity {
 }
 
 impl Verbosity {
-    fn is_verbose(&self) -> bool {
+    fn is_verbose(self) -> bool {
         match self {
             Verbosity::Verbose => true,
             _ => false,
diff --git a/crates/ra_hir_ty/src/traits.rs b/crates/ra_hir_ty/src/traits.rs
index c4dc857bc..4aabd66dc 100644
--- a/crates/ra_hir_ty/src/traits.rs
+++ b/crates/ra_hir_ty/src/traits.rs
@@ -1,10 +1,12 @@
 //! Trait solving using Chalk.
-use std::sync::{Arc, Mutex};
+use std::{
+    panic,
+    sync::{Arc, Mutex},
+};
 
 use chalk_ir::cast::Cast;
 use hir_def::{expr::ExprId, DefWithBodyId, ImplId, TraitId, TypeAliasId};
-use log::debug;
-use ra_db::{impl_intern_key, salsa, CrateId};
+use ra_db::{impl_intern_key, salsa, Canceled, CrateId};
 use ra_prof::profile;
 use rustc_hash::FxHashSet;
 
@@ -39,7 +41,7 @@ impl TraitSolver {
         goal: &chalk_ir::UCanonical<chalk_ir::InEnvironment<chalk_ir::Goal<TypeFamily>>>,
     ) -> Option<chalk_solve::Solution<TypeFamily>> {
         let context = ChalkContext { db, krate: self.krate };
-        debug!("solve goal: {:?}", goal);
+        log::debug!("solve goal: {:?}", goal);
         let mut solver = match self.inner.lock() {
             Ok(it) => it,
             // Our cancellation works via unwinding, but, as chalk is not
@@ -47,8 +49,28 @@ impl TraitSolver {
             // Ideally, we should also make chalk panic-safe.
             Err(_) => ra_db::Canceled::throw(),
         };
-        let solution = solver.solve(&context, goal);
-        debug!("solve({:?}) => {:?}", goal, solution);
+
+        let solution = panic::catch_unwind({
+            let solver = panic::AssertUnwindSafe(&mut solver);
+            let context = panic::AssertUnwindSafe(&context);
+            move || solver.0.solve(context.0, goal)
+        });
+
+        let solution = match solution {
+            Ok(it) => it,
+            Err(err) => {
+                if err.downcast_ref::<Canceled>().is_some() {
+                    panic::resume_unwind(err)
+                } else {
+                    log::error!("chalk panicked :-(");
+                    // Reset the solver, as it is not panic-safe.
+                    *solver = create_chalk_solver();
+                    None
+                }
+            }
+        };
+
+        log::debug!("solve({:?}) => {:?}", goal, solution);
         solution
     }
 }
@@ -70,9 +92,13 @@ pub(crate) fn trait_solver_query(
 ) -> TraitSolver {
     db.salsa_runtime().report_untracked_read();
     // krate parameter is just so we cache a unique solver per crate
+    log::debug!("Creating new solver for crate {:?}", krate);
+    TraitSolver { krate, inner: Arc::new(Mutex::new(create_chalk_solver())) }
+}
+
+fn create_chalk_solver() -> chalk_solve::Solver<TypeFamily> {
     let solver_choice = chalk_solve::SolverChoice::SLG { max_size: CHALK_SOLVER_MAX_SIZE };
-    debug!("Creating new solver for crate {:?}", krate);
-    TraitSolver { krate, inner: Arc::new(Mutex::new(solver_choice.into_solver())) }
+    solver_choice.into_solver()
 }
 
 /// Collects impls for the given trait in the whole dependency tree of `krate`.
@@ -181,7 +207,7 @@ pub(crate) fn trait_solve_query(
     goal: Canonical<InEnvironment<Obligation>>,
 ) -> Option<Solution> {
     let _p = profile("trait_solve_query");
-    debug!("trait_solve_query({})", goal.value.value.display(db));
+    log::debug!("trait_solve_query({})", goal.value.value.display(db));
 
     if let Obligation::Projection(pred) = &goal.value.value {
         if let Ty::Bound(_) = &pred.projection_ty.parameters[0] {
diff --git a/crates/ra_ide/src/call_hierarchy.rs b/crates/ra_ide/src/call_hierarchy.rs
index 1cb712e32..aa5d60c7b 100644
--- a/crates/ra_ide/src/call_hierarchy.rs
+++ b/crates/ra_ide/src/call_hierarchy.rs
@@ -121,7 +121,7 @@ pub(crate) fn outgoing_calls(db: &RootDatabase, position: FilePosition) -> Optio
                     Some(macro_def.to_nav(db))
                 }
             } {
-                Some((func_target.clone(), name_ref.value.text_range()))
+                Some((func_target, name_ref.value.text_range()))
             } else {
                 None
             }
diff --git a/crates/ra_ide/src/call_info.rs b/crates/ra_ide/src/call_info.rs
index a7023529b..72a68522e 100644
--- a/crates/ra_ide/src/call_info.rs
+++ b/crates/ra_ide/src/call_info.rs
@@ -1,10 +1,10 @@
 //! FIXME: write short doc here
-
 use hir::db::AstDatabase;
 use ra_syntax::{
     ast::{self, ArgListOwner},
     match_ast, AstNode, SyntaxNode,
 };
+
 use test_utils::tested_by;
 
 use crate::{
@@ -51,36 +51,39 @@ pub(crate) fn call_info(db: &RootDatabase, position: FilePosition) -> Option<Cal
     // If we have a calling expression let's find which argument we are on
     let num_params = call_info.parameters().len();
 
-    if num_params == 1 {
-        if !has_self {
-            call_info.active_parameter = Some(0);
-        }
-    } else if num_params > 1 {
-        // Count how many parameters into the call we are.
-        if let Some(arg_list) = calling_node.arg_list() {
-            // Number of arguments specified at the call site
-            let num_args_at_callsite = arg_list.args().count();
-
-            let arg_list_range = arg_list.syntax().text_range();
-            if !arg_list_range.contains_inclusive(position.offset) {
-                tested_by!(call_info_bad_offset);
-                return None;
+    match num_params {
+        0 => (),
+        1 => {
+            if !has_self {
+                call_info.active_parameter = Some(0);
             }
+        }
+        _ => {
+            if let Some(arg_list) = calling_node.arg_list() {
+                // Number of arguments specified at the call site
+                let num_args_at_callsite = arg_list.args().count();
+
+                let arg_list_range = arg_list.syntax().text_range();
+                if !arg_list_range.contains_inclusive(position.offset) {
+                    tested_by!(call_info_bad_offset);
+                    return None;
+                }
 
-            let mut param = std::cmp::min(
-                num_args_at_callsite,
-                arg_list
-                    .args()
-                    .take_while(|arg| arg.syntax().text_range().end() < position.offset)
-                    .count(),
-            );
-
-            // If we are in a method account for `self`
-            if has_self {
-                param += 1;
-            }
+                let mut param = std::cmp::min(
+                    num_args_at_callsite,
+                    arg_list
+                        .args()
+                        .take_while(|arg| arg.syntax().text_range().end() < position.offset)
+                        .count(),
+                );
+
+                // If we are in a method account for `self`
+                if has_self {
+                    param += 1;
+                }
 
-            call_info.active_parameter = Some(param);
+                call_info.active_parameter = Some(param);
+            }
         }
     }
 
diff --git a/crates/ra_ide/src/completion/complete_path.rs b/crates/ra_ide/src/completion/complete_path.rs
index cc1f7c830..0dce9dc2d 100644
--- a/crates/ra_ide/src/completion/complete_path.rs
+++ b/crates/ra_ide/src/completion/complete_path.rs
@@ -26,7 +26,7 @@ pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) {
                     }
                     if let ScopeDef::Unknown = def {
                         if let Some(name_ref) = ctx.name_ref_syntax.as_ref() {
-                            if &name_ref.syntax().text() == name.to_string().as_str() {
+                            if name_ref.syntax().text() == name.to_string().as_str() {
                                 // for `use self::foo<|>`, don't suggest `foo` as a completion
                                 tested_by!(dont_complete_current_use);
                                 continue;
diff --git a/crates/ra_ide/src/extend_selection.rs b/crates/ra_ide/src/extend_selection.rs
index 70b6fde82..930e0c4c2 100644
--- a/crates/ra_ide/src/extend_selection.rs
+++ b/crates/ra_ide/src/extend_selection.rs
@@ -339,7 +339,7 @@ mod tests {
         let (cursor, before) = extract_offset(before);
         let (analysis, file_id) = single_file(&before);
         let range = TextRange::offset_len(cursor, 0.into());
-        let mut frange = FileRange { file_id: file_id, range };
+        let mut frange = FileRange { file_id, range };
 
         for &after in afters {
             frange.range = analysis.extend_selection(frange).unwrap();
diff --git a/crates/ra_ide/src/references.rs b/crates/ra_ide/src/references.rs
index 4e52e0e7b..2c753dade 100644
--- a/crates/ra_ide/src/references.rs
+++ b/crates/ra_ide/src/references.rs
@@ -166,7 +166,7 @@ pub(crate) fn find_all_refs(
     Some(RangeInfo::new(range, ReferenceSearchResult { declaration, references }))
 }
 
-fn find_name<'a>(
+fn find_name(
     db: &RootDatabase,
     syntax: &SyntaxNode,
     position: FilePosition,
@@ -253,13 +253,10 @@ fn decl_access(
     let stmt = find_node_at_offset::<ast::LetStmt>(syntax, range.start())?;
     if let Some(_) = stmt.initializer() {
         let pat = stmt.pat()?;
-        match pat {
-            ast::Pat::BindPat(it) => {
-                if it.name()?.text().as_str() == name {
-                    return Some(ReferenceAccess::Write);
-                }
+        if let ast::Pat::BindPat(it) = pat {
+            if it.name()?.text().as_str() == name {
+                return Some(ReferenceAccess::Write);
             }
-            _ => {}
         }
     }
 
@@ -286,7 +283,7 @@ fn reference_access(kind: &NameKind, name_ref: &ast::NameRef) -> Option<Referenc
                             }
                         }
                     }
-                    return Some(ReferenceAccess::Read);
+                    Some(ReferenceAccess::Read)
                 },
                 _ => {None}
             }
diff --git a/crates/ra_ide/src/references/search_scope.rs b/crates/ra_ide/src/references/search_scope.rs
index 241dd358f..f8211a746 100644
--- a/crates/ra_ide/src/references/search_scope.rs
+++ b/crates/ra_ide/src/references/search_scope.rs
@@ -82,8 +82,7 @@ impl NameDefinition {
             return SearchScope::new(res);
         }
 
-        let vis =
-            self.visibility.as_ref().map(|v| v.syntax().to_string()).unwrap_or("".to_string());
+        let vis = self.visibility.as_ref().map(|v| v.syntax().to_string()).unwrap_or_default();
 
         if vis.as_str() == "pub(super)" {
             if let Some(parent_module) = self.container.parent(db) {
diff --git a/crates/ra_lsp_server/src/main.rs b/crates/ra_lsp_server/src/main.rs
index cdd925c9f..3879eeff2 100644
--- a/crates/ra_lsp_server/src/main.rs
+++ b/crates/ra_lsp_server/src/main.rs
@@ -47,6 +47,10 @@ fn run_server() -> Result<()> {
     let initialize_params = connection.initialize(server_capabilities)?;
     let initialize_params: lsp_types::InitializeParams = serde_json::from_value(initialize_params)?;
 
+    if let Some(client_info) = initialize_params.client_info {
+        log::info!("Client '{}' {}", client_info.name, client_info.version.unwrap_or_default());
+    }
+
     let cwd = std::env::current_dir()?;
     let root = initialize_params.root_uri.and_then(|it| it.to_file_path().ok()).unwrap_or(cwd);
 
diff --git a/crates/ra_lsp_server/src/main_loop.rs b/crates/ra_lsp_server/src/main_loop.rs
index 7a49cad86..84012b99d 100644
--- a/crates/ra_lsp_server/src/main_loop.rs
+++ b/crates/ra_lsp_server/src/main_loop.rs
@@ -417,6 +417,7 @@ fn loop_turn(
             let msg = format!("workspace loaded, {} rust packages", n_packages);
             show_message(req::MessageType::Info, msg, &connection.sender);
         }
+        world_state.check_watcher.update();
     }
 
     if state_changed {
diff --git a/crates/ra_syntax/src/ast/expr_extensions.rs b/crates/ra_syntax/src/ast/expr_extensions.rs
index 3dfecfe76..6da4b1309 100644
--- a/crates/ra_syntax/src/ast/expr_extensions.rs
+++ b/crates/ra_syntax/src/ast/expr_extensions.rs
@@ -127,8 +127,8 @@ pub enum BinOp {
 }
 
 impl BinOp {
-    pub fn is_assignment(&self) -> bool {
-        match *self {
+    pub fn is_assignment(self) -> bool {
+        match self {
             BinOp::Assignment
             | BinOp::AddAssign
             | BinOp::DivAssign