From f91fdd2ba0072d1a98e479fed3d0afb8d1ec4229 Mon Sep 17 00:00:00 2001
From: Antonio Scandurra <me@as-cii.com>
Date: Fri, 22 Apr 2022 15:43:23 +0200
Subject: [PATCH] Return `None` when prepare rename is not available on
 language server

---
 crates/lsp/src/lsp.rs             | 4 ++++
 crates/project/src/lsp_command.rs | 8 ++++++++
 2 files changed, 12 insertions(+)

diff --git a/crates/lsp/src/lsp.rs b/crates/lsp/src/lsp.rs
index c0b21eeeda..02bc0486f1 100644
--- a/crates/lsp/src/lsp.rs
+++ b/crates/lsp/src/lsp.rs
@@ -292,6 +292,10 @@ impl LanguageServer {
                         }),
                         ..Default::default()
                     }),
+                    rename: Some(RenameClientCapabilities {
+                        prepare_support: Some(true),
+                        ..Default::default()
+                    }),
                     ..Default::default()
                 }),
                 experimental: Some(json!({
diff --git a/crates/project/src/lsp_command.rs b/crates/project/src/lsp_command.rs
index 71ad489d07..1e86bb2719 100644
--- a/crates/project/src/lsp_command.rs
+++ b/crates/project/src/lsp_command.rs
@@ -86,6 +86,14 @@ impl LspCommand for PrepareRename {
     type LspRequest = lsp::request::PrepareRenameRequest;
     type ProtoRequest = proto::PrepareRename;
 
+    fn check_capabilities(&self, capabilities: &ServerCapabilities) -> bool {
+        if let Some(lsp::OneOf::Right(rename)) = &capabilities.rename_provider {
+            rename.prepare_provider == Some(true)
+        } else {
+            false
+        }
+    }
+
     fn to_lsp(&self, path: &Path, _: &AppContext) -> lsp::TextDocumentPositionParams {
         lsp::TextDocumentPositionParams {
             text_document: lsp::TextDocumentIdentifier {