`unused-function` checks recursive

3 files changed, 40 insertions, 8 deletions

diff --git a/changelog.md b/changelog.md
index 42435361..cb26ebd6 100644
--- a/changelog.md
+++ b/changelog.md
@@ -3,11 +3,12 @@
 ## 1.10.0
 * `NEW` workspace: supports `.dll`(`.so`) in `require`
 * `NEW` folding: `---@class`, `--#region` and docs of function
-* `NEW` dianostic: `count-down-loop`
+* `NEW` diagnostic: `count-down-loop`
 * `CHG` supports `~` in command line
 * `CHG` completion: improve workspace words
 * `CHG` completion: show words in string
 * `CHG` completion: split `for .. in` to `for .. ipairs` and `for ..pairs`
+* `CHG` diagnostic: `unused-function` checks recursive
 * `FIX` [#339](https://github.com/sumneko/lua-language-server/issues/339)
 
 ## 1.9.0
diff --git a/script/core/diagnostics/unused-function.lua b/script/core/diagnostics/unused-function.lua
index e6ae9386..41c239f9 100644
--- a/script/core/diagnostics/unused-function.lua
+++ b/script/core/diagnostics/unused-function.lua
@@ -23,25 +23,33 @@ return function (uri, callback)
     if not ast then
         return
     end
-    -- 只检查局部函数
-    guide.eachSourceType(ast.ast, 'function', function (source)
+
+    local cache = {}
+    local function checkFunction(source)
+        if cache[source] ~= nil then
+            return cache[source]
+        end
+        cache[source] = false
         local parent = source.parent
         if not parent then
-            return
+            return false
         end
         if  parent.type ~= 'local'
         and parent.type ~= 'setlocal' then
-            return
+            return false
         end
         if isToBeClosed(parent) then
-            return
+            return false
         end
         local hasGet
         local refs = vm.getRefs(source)
         for _, src in ipairs(refs) do
             if vm.isGet(src) then
-                hasGet = true
-                break
+                local func = guide.getParentFunction(src)
+                if not checkFunction(func) then
+                    hasGet = true
+                    break
+                end
             end
         end
         if not hasGet then
@@ -60,6 +68,14 @@ return function (uri, callback)
                     message = lang.script.DIAG_UNUSED_FUNCTION,
                 }
             end
+            cache[source] = true
+            return true
         end
+        return false
+    end
+
+    -- 只检查局部函数
+    guide.eachSourceType(ast.ast, 'function', function (source)
+        checkFunction(source)
     end)
 end
diff --git a/test/diagnostics/init.lua b/test/diagnostics/init.lua
index 4ec93acf..8a89179f 100644
--- a/test/diagnostics/init.lua
+++ b/test/diagnostics/init.lua
@@ -115,6 +115,21 @@ local <!x!>
 <!x!> = <!function () end!>
 ]]
 
+TEST([[
+<!local function x()
+end!>
+<!local function y()
+    x()
+end!>
+]],
+[[
+local function x()
+end
+local function <!y!>()
+    x()
+end
+]]
+)
 
 TEST [[
 print(<!x!>)