Only allow renames to valid identifiers

Author: detrumi

crates/ra_lsp_server/src/main_loop/handlers.rs

@@ -13,7 +13,7 @@ use ra_ide::{
     AssistId, FileId, FilePosition, FileRange, Query, Runnable, RunnableKind, SearchScope,
 };
 use ra_prof::profile;
-use ra_syntax::{AstNode, SyntaxKind, TextRange, TextUnit};
+use ra_syntax::{tokenize, AstNode, SyntaxKind, TextRange, TextUnit};
 use rustc_hash::FxHashMap;
 use serde::{Deserialize, Serialize};
 use serde_json::to_value;
@@ -506,6 +506,12 @@ pub fn handle_rename(world: WorldSnapshot, params: RenameParams) -> Result<Optio
         .into());
     }
 
+    // Only rename to valid identifiers
+    let tokens = tokenize(&params.new_name);
+    if tokens.len() != 1 || tokens[0].kind != SyntaxKind::IDENT {
+        return Ok(None);
+    }
+
     let optional_change = world.analysis().rename(position, &*params.new_name)?;
     let change = match optional_change {
         None => return Ok(None),