6 files changed, 85 insertions, 61 deletions

diff --git a/crates/libanalysis/src/imp.rs b/crates/libanalysis/src/imp.rs
index 004942e72..97802bd50 100644
--- a/crates/libanalysis/src/imp.rs
+++ b/crates/libanalysis/src/imp.rs
@@ -39,11 +39,11 @@ impl AnalysisHostImpl {
 
     pub fn analysis(
         &self,
-        file_resolver: impl FileResolver,
+        file_resolver: Arc<dyn FileResolver>,
     ) -> AnalysisImpl {
         AnalysisImpl {
             needs_reindex: AtomicBool::new(false),
-            file_resolver: Arc::new(file_resolver),
+            file_resolver,
             data: self.data.clone(),
         }
     }
@@ -78,7 +78,7 @@ impl AnalysisHostImpl {
 
 pub(crate) struct AnalysisImpl {
     needs_reindex: AtomicBool,
-    file_resolver: Arc<FileResolver>,
+    file_resolver: Arc<dyn FileResolver>,
     data: Arc<WorldData>,
 }
 
@@ -236,15 +236,13 @@ impl AnalysisImpl {
             ("add `#[derive]`", libeditor::add_derive(&file, offset).map(|f| f())),
             ("add impl", libeditor::add_impl(&file, offset).map(|f| f())),
         ];
-        let mut res = Vec::new();
-        for (name, local_edit) in actions {
-            if let Some(local_edit) = local_edit {
-                res.push(SourceChange::from_local_edit(
-                    file_id, name, local_edit
+        actions.into_iter()
+            .filter_map(|(name, local_edit)| {
+                Some(SourceChange::from_local_edit(
+                    file_id, name, local_edit?,
                 ))
-            }
-        }
-        res
+            })
+            .collect()
     }
 
     fn index_resolve(&self, name_ref: ast::NameRef) -> Vec<(FileId, FileSymbol)> {
diff --git a/crates/libanalysis/src/lib.rs b/crates/libanalysis/src/lib.rs
index 810228632..c25d31f4b 100644
--- a/crates/libanalysis/src/lib.rs
+++ b/crates/libanalysis/src/lib.rs
@@ -12,6 +12,8 @@ mod symbol_index;
 mod module_map;
 mod imp;
 
+use std::sync::Arc;
+
 use relative_path::{RelativePath, RelativePathBuf};
 use libsyntax2::{File, TextRange, TextUnit, AtomEdit};
 use imp::{AnalysisImpl, AnalysisHostImpl};
@@ -31,7 +33,7 @@ pub trait FileResolver: Send + Sync + 'static {
 
 #[derive(Debug)]
 pub struct AnalysisHost {
-    pub(crate) imp: AnalysisHostImpl
+    imp: AnalysisHostImpl
 }
 
 impl AnalysisHost {
@@ -39,7 +41,7 @@ impl AnalysisHost {
         AnalysisHost { imp: AnalysisHostImpl::new() }
     }
     pub fn analysis(&self, file_resolver: impl FileResolver) -> Analysis {
-        Analysis { imp: self.imp.analysis(file_resolver) }
+        Analysis { imp: self.imp.analysis(Arc::new(file_resolver)) }
     }
     pub fn change_file(&mut self, file_id: FileId, text: Option<String>) {
         self.change_files(::std::iter::once((file_id, text)));
@@ -121,7 +123,7 @@ impl Query {
 
 #[derive(Clone, Debug)]
 pub struct Analysis {
-    pub(crate) imp: AnalysisImpl
+    imp: AnalysisImpl
 }
 
 impl Analysis {
diff --git a/crates/server/src/main_loop/handlers.rs b/crates/server/src/main_loop/handlers.rs
index 45083b084..6b70399b0 100644
--- a/crates/server/src/main_loop/handlers.rs
+++ b/crates/server/src/main_loop/handlers.rs
@@ -1,7 +1,7 @@
 use std::collections::HashMap;
 
 use languageserver_types::{
-    Diagnostic, DiagnosticSeverity, Url, DocumentSymbol,
+    Diagnostic, DiagnosticSeverity, DocumentSymbol,
     Command, TextDocumentIdentifier,
     SymbolInformation, Position, Location, TextEdit,
     CompletionItem, InsertTextFormat, CompletionItemKind,
@@ -325,9 +325,9 @@ pub fn handle_code_action(
 
 pub fn publish_diagnostics(
     world: ServerWorld,
-    uri: Url
+    file_id: FileId,
 ) -> Result<req::PublishDiagnosticsParams> {
-    let file_id = world.uri_to_file_id(&uri)?;
+    let uri = world.file_id_to_uri(file_id)?;
     let line_index = world.analysis().file_line_index(file_id);
     let diagnostics = world.analysis().diagnostics(file_id)
         .into_iter()
@@ -344,9 +344,9 @@ pub fn publish_diagnostics(
 
 pub fn publish_decorations(
     world: ServerWorld,
-    uri: Url
+    file_id: FileId,
 ) -> Result<req::PublishDecorationsParams> {
-    let file_id = world.uri_to_file_id(&uri)?;
+    let uri = world.file_id_to_uri(file_id)?;
     Ok(req::PublishDecorationsParams {
         uri,
         decorations: highlight(&world, file_id),
diff --git a/crates/server/src/main_loop/mod.rs b/crates/server/src/main_loop/mod.rs
index 0f66248a5..cd17cab56 100644
--- a/crates/server/src/main_loop/mod.rs
+++ b/crates/server/src/main_loop/mod.rs
@@ -1,4 +1,5 @@
 mod handlers;
+mod subscriptions;
 
 use std::{
     collections::{HashSet},
@@ -6,7 +7,7 @@ use std::{
 
 use threadpool::ThreadPool;
 use crossbeam_channel::{Sender, Receiver};
-use languageserver_types::Url;
+use libanalysis::FileId;
 
 use {
     req, dispatch,
@@ -14,6 +15,7 @@ use {
     io::{Io, RawMsg, RawRequest, RawNotification},
     vfs::FileEvent,
     server_world::{ServerWorldState, ServerWorld},
+    main_loop::subscriptions::{Subscriptions},
 };
 
 pub(super) fn main_loop(
@@ -28,6 +30,7 @@ pub(super) fn main_loop(
 
     let mut pending_requests: HashSet<u64> = HashSet::new();
     let mut fs_events_receiver = Some(&fs_events_receiver);
+    let mut subs = Subscriptions::new();
     loop {
         enum Event {
             Msg(RawMsg),
@@ -47,7 +50,7 @@ pub(super) fn main_loop(
                 None => Event::FsWatcherDead,
             }
         };
-
+        let mut state_changed = false;
         match event {
             Event::ReceiverDead => {
                 io.cleanup_receiver()?;
@@ -70,6 +73,7 @@ pub(super) fn main_loop(
             Event::Fs(events) => {
                 trace!("fs change, {} events", events.len());
                 state.apply_fs_changes(events);
+                state_changed = true;
             }
             Event::Msg(msg) => {
                 match msg {
@@ -79,7 +83,8 @@ pub(super) fn main_loop(
                         }
                     }
                     RawMsg::Notification(not) => {
-                        on_notification(io, &mut state, pool, &task_sender, not)?
+                        on_notification(io, &mut state, &mut subs, not)?;
+                        state_changed = true;
                     }
                     RawMsg::Response(resp) => {
                         if !pending_requests.remove(&resp.id) {
@@ -89,6 +94,15 @@ pub(super) fn main_loop(
                 }
             }
         };
+
+        if state_changed {
+            update_file_notifications_on_threadpool(
+                pool,
+                state.snapshot(),
+                task_sender.clone(),
+                subs.subscriptions(),
+            )
+        }
     }
 }
 
@@ -140,8 +154,7 @@ fn on_request(
 fn on_notification(
     io: &mut Io,
     state: &mut ServerWorldState,
-    pool: &ThreadPool,
-    sender: &Sender<Task>,
+    subs: &mut Subscriptions,
     not: RawNotification,
 ) -> Result<()> {
     let mut not = Some(not);
@@ -149,13 +162,8 @@ fn on_notification(
         let uri = params.text_document.uri;
         let path = uri.to_file_path()
             .map_err(|()| format_err!("invalid uri: {}", uri))?;
-        state.add_mem_file(path, params.text_document.text);
-        update_file_notifications_on_threadpool(
-            pool,
-            state.snapshot(),
-            sender.clone(),
-            uri,
-        );
+        let file_id = state.add_mem_file(path, params.text_document.text);
+        subs.add_sub(file_id);
         Ok(())
     })?;
     dispatch::handle_notification::<req::DidChangeTextDocument, _>(&mut not, |mut params| {
@@ -166,23 +174,15 @@ fn on_notification(
             .ok_or_else(|| format_err!("empty changes"))?
             .text;
         state.change_mem_file(path.as_path(), text)?;
-        update_file_notifications_on_threadpool(
-            pool,
-            state.snapshot(),
-            sender.clone(),
-            uri,
-        );
         Ok(())
     })?;
     dispatch::handle_notification::<req::DidCloseTextDocument, _>(&mut not, |params| {
         let uri = params.text_document.uri;
         let path = uri.to_file_path()
             .map_err(|()| format_err!("invalid uri: {}", uri))?;
-        state.remove_mem_file(path.as_path())?;
-        let not = req::PublishDiagnosticsParams {
-            uri,
-            diagnostics: Vec::new(),
-        };
+        let file_id = state.remove_mem_file(path.as_path())?;
+        subs.remove_sub(file_id);
+        let not = req::PublishDiagnosticsParams { uri, diagnostics: Vec::new() };
         let not = dispatch::send_notification::<req::PublishDiagnostics>(not);
         io.send(RawMsg::Notification(not));
         Ok(())
@@ -227,25 +227,27 @@ fn update_file_notifications_on_threadpool(
     pool: &ThreadPool,
     world: ServerWorld,
     sender: Sender<Task>,
-    uri: Url,
+    subscriptions: Vec<FileId>,
 ) {
     pool.execute(move || {
-        match handlers::publish_diagnostics(world.clone(), uri.clone()) {
-            Err(e) => {
-                error!("failed to compute diagnostics: {:?}", e)
-            }
-            Ok(params) => {
-                let not = dispatch::send_notification::<req::PublishDiagnostics>(params);
-                sender.send(Task::Notify(not));
-            }
-        }
-        match handlers::publish_decorations(world, uri) {
-            Err(e) => {
-                error!("failed to compute decorations: {:?}", e)
+        for file_id in subscriptions {
+            match handlers::publish_diagnostics(world.clone(), file_id) {
+                Err(e) => {
+                    error!("failed to compute diagnostics: {:?}", e)
+                }
+                Ok(params) => {
+                    let not = dispatch::send_notification::<req::PublishDiagnostics>(params);
+                    sender.send(Task::Notify(not));
+                }
             }
-            Ok(params) => {
-                let not = dispatch::send_notification::<req::PublishDecorations>(params);
-                sender.send(Task::Notify(not))
+            match handlers::publish_decorations(world.clone(), file_id) {
+                Err(e) => {
+                    error!("failed to compute decorations: {:?}", e)
+                }
+                Ok(params) => {
+                    let not = dispatch::send_notification::<req::PublishDecorations>(params);
+                    sender.send(Task::Notify(not))
+                }
             }
         }
     });
diff --git a/crates/server/src/main_loop/subscriptions.rs b/crates/server/src/main_loop/subscriptions.rs
new file mode 100644
index 000000000..963096aef
--- /dev/null
+++ b/crates/server/src/main_loop/subscriptions.rs
@@ -0,0 +1,21 @@
+use std::collections::HashSet;
+use libanalysis::FileId;
+
+pub struct Subscriptions {
+    subs: HashSet<FileId>,
+}
+
+impl Subscriptions {
+    pub fn new() -> Subscriptions {
+        Subscriptions { subs: HashSet::new() }
+    }
+    pub fn add_sub(&mut self, file_id: FileId) {
+        self.subs.insert(file_id);
+    }
+    pub fn remove_sub(&mut self, file_id: FileId) {
+        self.subs.remove(&file_id);
+    }
+    pub fn subscriptions(&self) -> Vec<FileId> {
+        self.subs.iter().cloned().collect()
+    }
+}
diff --git a/crates/server/src/server_world.rs b/crates/server/src/server_world.rs
index 9ba7df0b8..d99ef661e 100644
--- a/crates/server/src/server_world.rs
+++ b/crates/server/src/server_world.rs
@@ -61,10 +61,11 @@ impl ServerWorldState {
         self.analysis_host.change_files(changes);
     }
 
-    pub fn add_mem_file(&mut self, path: PathBuf, text: String) {
+    pub fn add_mem_file(&mut self, path: PathBuf, text: String) -> FileId {
         let file_id = self.path_map.get_or_insert(path);
         self.mem_map.insert(file_id, None);
         self.analysis_host.change_file(file_id, Some(text));
+        file_id
     }
 
     pub fn change_mem_file(&mut self, path: &Path, text: String) -> Result<()> {
@@ -75,7 +76,7 @@ impl ServerWorldState {
         Ok(())
     }
 
-    pub fn remove_mem_file(&mut self, path: &Path) -> Result<()> {
+    pub fn remove_mem_file(&mut self, path: &Path) -> Result<FileId> {
         let file_id = self.path_map.get_id(path).ok_or_else(|| {
             format_err!("change to unknown file: {}", path.display())
         })?;
@@ -86,7 +87,7 @@ impl ServerWorldState {
         // Do this via file watcher ideally.
         let text = fs::read_to_string(path).ok();
         self.analysis_host.change_file(file_id, text);
-        Ok(())
+        Ok(file_id)
     }
 
     pub fn snapshot(&self) -> ServerWorld {