From ca336c681d263cd52f2aba40a8d0b0646d5a9f3d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?C=C3=A9dric=20Barreteau?=
 <cbarrete@users.noreply.github.com>
Date: Tue, 18 May 2021 17:32:40 -0400
Subject: [PATCH] lsp: handle unsupported call hierarchy call

---
 runtime/lua/vim/lsp/buf.lua | 24 ++++++++++++++----------
 1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/runtime/lua/vim/lsp/buf.lua b/runtime/lua/vim/lsp/buf.lua
index 341a3e82fc..5dd7109bb0 100644
--- a/runtime/lua/vim/lsp/buf.lua
+++ b/runtime/lua/vim/lsp/buf.lua
@@ -297,26 +297,30 @@ local function pick_call_hierarchy_item(call_hierarchy_items)
   return choice
 end
 
+local function call_hierarchy(method)
+  local params = util.make_position_params()
+  request('textDocument/prepareCallHierarchy', params, function(err, _, result)
+    if err then
+      vim.notify(err.message, vim.log.levels.WARN)
+      return
+    end
+    local call_hierarchy_item = pick_call_hierarchy_item(result)
+    vim.lsp.buf_request(0, method, { item = call_hierarchy_item })
+  end)
+end
+
 --- Lists all the call sites of the symbol under the cursor in the
 --- |quickfix| window. If the symbol can resolve to multiple
 --- items, the user can pick one in the |inputlist|.
 function M.incoming_calls()
-  local params = util.make_position_params()
-  request('textDocument/prepareCallHierarchy', params, function(_, _, result)
-    local call_hierarchy_item = pick_call_hierarchy_item(result)
-    vim.lsp.buf_request(0, 'callHierarchy/incomingCalls', { item = call_hierarchy_item })
-  end)
+  call_hierarchy('callHierarchy/incomingCalls')
 end
 
 --- Lists all the items that are called by the symbol under the
 --- cursor in the |quickfix| window. If the symbol can resolve to
 --- multiple items, the user can pick one in the |inputlist|.
 function M.outgoing_calls()
-  local params = util.make_position_params()
-  request('textDocument/prepareCallHierarchy', params, function(_, _, result)
-    local call_hierarchy_item = pick_call_hierarchy_item(result)
-    vim.lsp.buf_request(0, 'callHierarchy/outgoingCalls', { item = call_hierarchy_item })
-  end)
+  call_hierarchy('callHierarchy/outgoingCalls')
 end
 
 --- List workspace folders.