From 73836cdbbc928f3512156f0bc0166e5a39ad9864 Mon Sep 17 00:00:00 2001
From: Aleksey Kladov <aleksey.kladov@gmail.com>
Date: Sun, 20 Jan 2019 21:05:01 +0300
Subject: [PATCH] extend selection expands macros and can totally panic

---
 crates/ra_ide_api/src/extend_selection.rs      |  2 +-
 crates/ra_ide_api/src/lib.rs                   |  4 ++--
 crates/ra_lsp_server/src/main_loop/handlers.rs | 12 ++++++++----
 3 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/crates/ra_ide_api/src/extend_selection.rs b/crates/ra_ide_api/src/extend_selection.rs
index 9f0ab2f1c81..718b4def557 100644
--- a/crates/ra_ide_api/src/extend_selection.rs
+++ b/crates/ra_ide_api/src/extend_selection.rs
@@ -51,7 +51,7 @@ fn main() {
             }
         ",
         );
-        let r = analysis.extend_selection(frange);
+        let r = analysis.extend_selection(frange).unwrap();
         assert_eq!(r, TextRange::from_to(51.into(), 56.into()));
     }
 }
diff --git a/crates/ra_ide_api/src/lib.rs b/crates/ra_ide_api/src/lib.rs
index e41d85e7098..919d248e2cd 100644
--- a/crates/ra_ide_api/src/lib.rs
+++ b/crates/ra_ide_api/src/lib.rs
@@ -310,8 +310,8 @@ pub fn file_line_index(&self, file_id: FileId) -> Arc<LineIndex> {
     }
 
     /// Selects the next syntactic nodes encopasing the range.
-    pub fn extend_selection(&self, frange: FileRange) -> TextRange {
-        extend_selection::extend_selection(&self.db, frange)
+    pub fn extend_selection(&self, frange: FileRange) -> Cancelable<TextRange> {
+        self.with_db(|db| extend_selection::extend_selection(db, frange))
     }
 
     /// Returns position of the mathcing brace (all types of braces are
diff --git a/crates/ra_lsp_server/src/main_loop/handlers.rs b/crates/ra_lsp_server/src/main_loop/handlers.rs
index 5cd8abbb9b5..02393f728b1 100644
--- a/crates/ra_lsp_server/src/main_loop/handlers.rs
+++ b/crates/ra_lsp_server/src/main_loop/handlers.rs
@@ -8,7 +8,7 @@
     WorkspaceEdit
 };
 use ra_ide_api::{
-    FileId, FilePosition, FileRange, FoldKind, Query, RangeInfo, RunnableKind, Severity,
+    FileId, FilePosition, FileRange, FoldKind, Query, RangeInfo, RunnableKind, Severity, Cancelable,
 };
 use ra_syntax::{AstNode, TextUnit};
 use rustc_hash::FxHashMap;
@@ -40,9 +40,13 @@ pub fn handle_extend_selection(
         .into_iter()
         .map_conv_with(&line_index)
         .map(|range| FileRange { file_id, range })
-        .map(|frange| world.analysis().extend_selection(frange))
-        .map_conv_with(&line_index)
-        .collect();
+        .map(|frange| {
+            world
+                .analysis()
+                .extend_selection(frange)
+                .map(|it| it.conv_with(&line_index))
+        })
+        .collect::<Cancelable<Vec<_>>>()?;
     Ok(req::ExtendSelectionResult { selections })
 }