3 files changed, 14 insertions, 3 deletions

diff --git a/crates/ra_lsp_server/src/main_loop.rs b/crates/ra_lsp_server/src/main_loop.rs
index 726c758aa..03c834dbc 100644
--- a/crates/ra_lsp_server/src/main_loop.rs
+++ b/crates/ra_lsp_server/src/main_loop.rs
@@ -65,7 +65,7 @@ pub fn main_loop(
     let workspaces = match ws_worker.recv().unwrap() {
         Ok(ws) => vec![ws],
         Err(e) => {
-            log::warn!("loading workspace failed: {}", e);
+            log::error!("loading workspace failed: {}", e);
             Vec::new()
         }
     };
diff --git a/crates/ra_lsp_server/src/main_loop/handlers.rs b/crates/ra_lsp_server/src/main_loop/handlers.rs
index 7f6146b6c..a781df181 100644
--- a/crates/ra_lsp_server/src/main_loop/handlers.rs
+++ b/crates/ra_lsp_server/src/main_loop/handlers.rs
@@ -4,7 +4,7 @@ use gen_lsp_server::ErrorCode;
 use languageserver_types::{
     CodeActionResponse, Command, CodeLens, Diagnostic, DiagnosticSeverity, DocumentFormattingParams,
     DocumentHighlight, DocumentSymbol, Documentation, FoldingRange, FoldingRangeKind,
-    FoldingRangeParams, Hover, HoverContents, Location, MarkedString, MarkupContent, MarkupKind,
+    FoldingRangeParams, Hover, HoverContents, Location, MarkupContent, MarkupKind,
     ParameterInformation, ParameterLabel, Position, PrepareRenameResponse, Range, RenameParams,
     SignatureInformation, SymbolInformation, TextDocumentIdentifier, TextEdit, WorkspaceEdit,
 };
@@ -422,7 +422,10 @@ pub fn handle_hover(
     let line_index = world.analysis.file_line_index(position.file_id);
     let range = info.range.conv_with(&line_index);
     let res = Hover {
-        contents: HoverContents::Scalar(MarkedString::String(info.info)),
+        contents: HoverContents::Markup(MarkupContent {
+            kind: MarkupKind::Markdown,
+            value: info.info,
+        }),
         range: Some(range),
     };
     Ok(Some(res))
diff --git a/crates/ra_lsp_server/src/project_model/sysroot.rs b/crates/ra_lsp_server/src/project_model/sysroot.rs
index 1dbab57f8..3b2fa070b 100644
--- a/crates/ra_lsp_server/src/project_model/sysroot.rs
+++ b/crates/ra_lsp_server/src/project_model/sysroot.rs
@@ -44,6 +44,14 @@ impl Sysroot {
         let stdout = String::from_utf8(rustc_output.stdout)?;
         let sysroot_path = Path::new(stdout.trim());
         let src = sysroot_path.join("lib/rustlib/src/rust/src");
+        if !src.exists() {
+            failure::bail!(
+                "can't load standard library from sysroot\n\
+                 {:?}\n\
+                 try running `rustup component add rust-src`",
+                src,
+            );
+        }
 
         let mut sysroot = Sysroot {
             crates: Arena::default(),