fix #1637

5 files changed, 54 insertions, 22 deletions

diff --git a/changelog.md b/changelog.md
index 90e535e5..9401308f 100644
--- a/changelog.md
+++ b/changelog.md
@@ -40,6 +40,7 @@ server will generate `doc.json` and `doc.md` in `LOGPATH`.
 * `FIX` [#1599]
 * `FIX` [#1606]
 * `FIX` [#1608]
+* `FIX` [#1637]
 
 [#1177]: https://github.com/sumneko/lua-language-server/issues/1177
 [#1458]: https://github.com/sumneko/lua-language-server/issues/1458
@@ -53,6 +54,7 @@ server will generate `doc.json` and `doc.md` in `LOGPATH`.
 [#1599]: https://github.com/sumneko/lua-language-server/issues/1599
 [#1606]: https://github.com/sumneko/lua-language-server/issues/1606
 [#1608]: https://github.com/sumneko/lua-language-server/issues/1608
+[#1637]: https://github.com/sumneko/lua-language-server/issues/1637
 
 ## 3.5.6
 `2022-9-16`
diff --git a/meta/template/io.lua b/meta/template/io.lua
index 66a77d38..d685128b 100644
--- a/meta/template/io.lua
+++ b/meta/template/io.lua
@@ -101,7 +101,7 @@ function io.write(...) end
 ---@class file*
 local file = {}
 
----@alias readmode integer
+---@alias readmode integer|string
 ---#if VERSION >= 5.3 then
 ---| '"n"'  # ---#DESTAIL 'readmode.n'
 ---| '"a"'  # ---#DESTAIL 'readmode.a'
diff --git a/script/progress.lua b/script/progress.lua
index f1f371f5..5fffc9a3 100644
--- a/script/progress.lua
+++ b/script/progress.lua
@@ -145,7 +145,7 @@ function m.update()
 end
 
 ---创建一个进度条
----@param uri   uri
+---@param uri?  uri
 ---@param title string # 标题
 ---@param delay number # 至少经过这么久之后才会显示出来
 function m.create(uri, title, delay)
diff --git a/script/vm/type.lua b/script/vm/type.lua
index be3eff98..15504878 100644
--- a/script/vm/type.lua
+++ b/script/vm/type.lua
@@ -89,11 +89,27 @@ local function checkValue(parent, child)
     return true
 end
 
+---@param name string
+---@param suri uri
+---@return boolean
+local function isAlias(name, suri)
+    local global = vm.getGlobal('type', name)
+    if not global then
+        return false
+    end
+    for _, set in ipairs(global:getSets(suri)) do
+        if set.type == 'doc.alias' then
+            return true
+        end
+    end
+    return false
+end
+
 ---@param uri uri
 ---@param child  vm.node|string|vm.node.object
 ---@param parent vm.node|string|vm.node.object
 ---@param mark?  table
----@return boolean
+---@return boolean?
 function vm.isSubType(uri, child, parent, mark)
     mark = mark or {}
 
@@ -109,24 +125,24 @@ function vm.isSubType(uri, child, parent, mark)
             for n in child:eachObject() do
                 if getNodeName(n) then
                     hasKnownType = true
-                    if vm.isSubType(uri, n, parent, mark) then
+                    if vm.isSubType(uri, n, parent, mark) == true then
                         return true
                     end
                 end
             end
             return not hasKnownType
         else
-            local weakNil   = config.get(uri, 'Lua.type.weakNilCheck')
+            local weakNil = config.get(uri, 'Lua.type.weakNilCheck')
             for n in child:eachObject() do
                 local nodeName = getNodeName(n)
                 if  nodeName
                 and not (nodeName == 'nil' and weakNil)
-                and not vm.isSubType(uri, n, parent, mark) then
+                and vm.isSubType(uri, n, parent, mark) == false then
                     return false
                 end
             end
             if not weakNil and child:isOptional() then
-                if not vm.isSubType(uri, 'nil', parent, mark) then
+                if vm.isSubType(uri, 'nil', parent, mark) == false then
                     return false
                 end
             end
@@ -134,6 +150,18 @@ function vm.isSubType(uri, child, parent, mark)
         end
     end
 
+    ---@cast child  vm.node.object
+    local childName = getNodeName(child)
+    if childName == 'any'
+    or childName == 'unknown' then
+        return true
+    end
+
+    if not childName
+    or isAlias(childName, uri) then
+        return nil
+    end
+
     if type(parent) == 'string' then
         local global = vm.getGlobal('type', parent)
         if not global then
@@ -143,7 +171,7 @@ function vm.isSubType(uri, child, parent, mark)
     elseif parent.type == 'vm.node' then
         for n in parent:eachObject() do
             if  getNodeName(n)
-            and vm.isSubType(uri, child, n, mark) then
+            and vm.isSubType(uri, child, n, mark) == true then
                 return true
             end
             if n.type == 'doc.generic.name' then
@@ -151,27 +179,26 @@ function vm.isSubType(uri, child, parent, mark)
             end
         end
         if parent:isOptional() then
-            if vm.isSubType(uri, child, 'nil', mark) then
+            if vm.isSubType(uri, child, 'nil', mark) == true then
                 return true
             end
         end
         return false
     end
 
-    ---@cast child  vm.node.object
     ---@cast parent vm.node.object
 
-    local childName  = getNodeName(child)
     local parentName = getNodeName(parent)
-    if childName  == 'any'
-    or parentName == 'any'
-    or childName  == 'unknown'
-    or parentName == 'unknown'
-    or not childName
-    or not parentName then
+    if parentName == 'any'
+    or parentName == 'unknown' then
         return true
     end
 
+    if not parentName
+    or isAlias(parentName, uri) then
+        return nil
+    end
+
     if childName == parentName then
         if not checkValue(parent, child) then
             return false
@@ -223,15 +250,11 @@ function vm.isSubType(uri, child, parent, mark)
                     for _, ext in ipairs(set.extends) do
                         if  ext.type == 'doc.extends.name'
                         and (not isBasicType or guide.isBasicType(ext[1]))
-                        and vm.isSubType(uri, ext[1], parent, mark) then
+                        and vm.isSubType(uri, ext[1], parent, mark) == true then
                             return true
                         end
                     end
                 end
-                if set.type == 'doc.alias'
-                or set.type == 'doc.enum' then
-                    return true
-                end
             end
         end
         mark[childName] = nil
diff --git a/test/diagnostics/type-check.lua b/test/diagnostics/type-check.lua
index a938f14c..bdba855b 100644
--- a/test/diagnostics/type-check.lua
+++ b/test/diagnostics/type-check.lua
@@ -834,6 +834,13 @@ local function f(x)
 end
 ]]
 
+TEST [[
+---@alias test boolean
+
+---@type test
+local <!test!> = 4
+]]
+
 config.remove(nil, 'Lua.diagnostics.disable', 'unused-local')
 config.remove(nil, 'Lua.diagnostics.disable', 'unused-function')
 config.remove(nil, 'Lua.diagnostics.disable', 'undefined-global')