fix #1403

Author: sumneko

changelog.md

@@ -2,6 +2,7 @@
 
 ## 3.5.2
 * `FIX` [#1395](https://github.com/sumneko/lua-language-server/issues/1395)
+* `FIX` [#1403](https://github.com/sumneko/lua-language-server/issues/1403)
 
 ## 3.5.1
 `2022-7-26`

script/core/completion/completion.lua

@@ -2037,7 +2037,9 @@ local function tryluaDocOfFunction(doc, results)
     if not doc.bindSource then
         return
     end
-    local func = doc.bindSource.type == 'function' and doc.bindSource or nil
+    local func = (doc.bindSource.type == 'function' and doc.bindSource)
+              or (doc.bindSource.value and doc.bindSource.value.type == 'function' and doc.bindSource.value)
+              or nil
     if not func then
         return
     end

test/completion/common.lua

@@ -3713,3 +3713,9 @@ TEST [[
 (function (results)
     assert(#results > 2)
 end)
+
+TEST [[
+---<??>
+local x = function (x, y) end
+]]
+(EXISTS)