3 files changed, 33 insertions, 1 deletions

diff --git a/crates/server/src/main_loop/handlers.rs b/crates/server/src/main_loop/handlers.rs
index b47cbc0fc..ae362ddaa 100644
--- a/crates/server/src/main_loop/handlers.rs
+++ b/crates/server/src/main_loop/handlers.rs
@@ -3,7 +3,7 @@ use std::collections::HashMap;
 use languageserver_types::{
     Diagnostic, DiagnosticSeverity, Url, DocumentSymbol,
     Command, TextDocumentIdentifier, WorkspaceEdit,
-    SymbolInformation, Position, Location,
+    SymbolInformation, Position, Location, TextEdit,
 };
 use libanalysis::{Query};
 use libeditor;
@@ -58,6 +58,18 @@ pub fn handle_find_matching_brace(
     Ok(res)
 }
 
+pub fn handle_join_lines(
+    world: ServerWorld,
+    params: req::JoinLinesParams,
+) -> Result<Vec<TextEdit>> {
+    let file_id = params.text_document.try_conv_with(&world)?;
+    let file = world.analysis().file_syntax(file_id)?;
+    let line_index = world.analysis().file_line_index(file_id)?;
+    let range = params.range.conv_with(&line_index);
+    let res = libeditor::join_lines(&file, range);
+    Ok(res.edit.conv_with(&line_index))
+}
+
 pub fn handle_document_symbol(
     world: ServerWorld,
     params: req::DocumentSymbolParams,
diff --git a/crates/server/src/main_loop/mod.rs b/crates/server/src/main_loop/mod.rs
index 9499b826c..1e65041e2 100644
--- a/crates/server/src/main_loop/mod.rs
+++ b/crates/server/src/main_loop/mod.rs
@@ -27,6 +27,7 @@ use {
         handle_goto_definition,
         handle_find_matching_brace,
         handle_parent_module,
+        handle_join_lines,
     },
 };
 
@@ -145,6 +146,9 @@ fn on_request(
     handle_request_on_threadpool::<req::ParentModule>(
         &mut req, pool, world, sender, handle_parent_module,
     )?;
+    handle_request_on_threadpool::<req::JoinLines>(
+        &mut req, pool, world, sender, handle_join_lines,
+    )?;
     dispatch::handle_request::<req::ExecuteCommand, _>(&mut req, |params, resp| {
         io.send(RawMsg::Response(resp.into_response(Ok(None))?));
 
diff --git a/crates/server/src/req.rs b/crates/server/src/req.rs
index a8aa24629..c431deeb4 100644
--- a/crates/server/src/req.rs
+++ b/crates/server/src/req.rs
@@ -10,6 +10,7 @@ pub use languageserver_types::{
     ExecuteCommandParams,
     WorkspaceSymbolParams,
     TextDocumentPositionParams,
+    TextEdit,
 };
 
 
@@ -117,3 +118,18 @@ impl Request for ParentModule {
     type Result = Vec<Location>;
     const METHOD: &'static str = "m/parentModule";
 }
+
+pub enum JoinLines {}
+
+impl Request for JoinLines {
+    type Params = JoinLinesParams;
+    type Result = Vec<TextEdit>;
+    const METHOD: &'static str = "m/joinLines";
+}
+
+#[derive(Deserialize, Debug)]
+#[serde(rename_all = "camelCase")]
+pub struct JoinLinesParams {
+    pub text_document: TextDocumentIdentifier,
+    pub range: Range,
+}