Don't re-read open files from disk when reloading a workspace

Author: lnicola

crates/rust-analyzer/src/reload.rs

@@ -201,11 +201,14 @@ impl GlobalState {
             let mut crate_graph = CrateGraph::default();
             let vfs = &mut self.vfs.write().0;
             let loader = &mut self.loader;
+            let mem_docs = &self.mem_docs;
             let mut load = |path: &AbsPath| {
-                let contents = loader.handle.load_sync(path);
-                let path = vfs::VfsPath::from(path.to_path_buf());
-                vfs.set_file_contents(path.clone(), contents);
-                vfs.file_id(&path)
+                let vfs_path = vfs::VfsPath::from(path.to_path_buf());
+                if !mem_docs.contains_key(&vfs_path) {
+                    let contents = loader.handle.load_sync(path);
+                    vfs.set_file_contents(vfs_path.clone(), contents);
+                }
+                vfs.file_id(&vfs_path)
             };
             for ws in workspaces.iter() {
                 crate_graph.extend(ws.to_crate_graph(