fix(denols): ignore virtual text error #1995

If you open a file and immediately try to go to definition this error happens:
```
{["error"]={["message"]="Method not found: deno/virtualTextDocument",["code"]="-32601"}}
{["error"]={["message"]="Method not found: deno/virtualTextDocument",["code"]="-32601"}}
{["error"]={["code"]="-32601",["message"]="Method not found: deno/virtualTextDocument"}}
{["error"]={["code"]="-32601",["message"]="Method not found: deno/virtualTextDocument"}}
```

Seems to be a race condition where the virtual text handling is not ready yet.
Because this error is unhelpful and the gotodefinition works normally after
a couple of seconds, just ignore it.

1 files changed, 17 insertions, 11 deletions

diff --git a/lua/lspconfig/server_configurations/denols.lua b/lua/lspconfig/server_configurations/denols.lua
index 315ac9ba..6602d9e4 100644
--- a/lua/lspconfig/server_configurations/denols.lua
+++ b/lua/lspconfig/server_configurations/denols.lua
@@ -18,19 +18,25 @@ local function virtual_text_document_handler(uri, result)
   end
 
   for client_id, res in pairs(result) do
-    local lines = vim.split(res.result, '\n')
-    local bufnr = vim.uri_to_bufnr(uri)
+    -- Error might be present because of race, deno server will eventually send a result. #1995
+    if res.error ~= nil then
+        require('vim.lsp.log').warn('deno/virtual_text_document handler failed (might be a temporary issue), error: '
+            .. tostring(res.error))
+    else
+        local lines = vim.split(res.result, '\n')
+        local bufnr = vim.uri_to_bufnr(uri)
 
-    local current_buf = vim.api.nvim_buf_get_lines(bufnr, 0, -1, false)
-    if #current_buf ~= 0 then
-      return nil
-    end
+        local current_buf = vim.api.nvim_buf_get_lines(bufnr, 0, -1, false)
+        if #current_buf ~= 0 then
+          return nil
+        end
 
-    vim.api.nvim_buf_set_lines(bufnr, 0, -1, nil, lines)
-    vim.api.nvim_buf_set_option(bufnr, 'readonly', true)
-    vim.api.nvim_buf_set_option(bufnr, 'modified', false)
-    vim.api.nvim_buf_set_option(bufnr, 'modifiable', false)
-    lsp.buf_attach_client(bufnr, client_id)
+        vim.api.nvim_buf_set_lines(bufnr, 0, -1, nil, lines)
+        vim.api.nvim_buf_set_option(bufnr, 'readonly', true)
+        vim.api.nvim_buf_set_option(bufnr, 'modified', false)
+        vim.api.nvim_buf_set_option(bufnr, 'modifiable', false)
+        lsp.buf_attach_client(bufnr, client_id)
+    end
   end
 end