6 files changed, 65 insertions, 3 deletions
diff --git a/script-beta/await.lua b/script-beta/await.lua
index 00c2bcd0..95a63f4a 100644
--- a/script-beta/await.lua
+++ b/script-beta/await.lua
@@ -117,6 +117,9 @@ function m.wait(callback, ...)
             return
         end
         waked = true
+        if coroutine.status(co) == 'dead' then
+            return
+        end
         return m.checkResult(co, coroutine.resume(co, ...))
     end, ...)
     return coroutine.yield()
diff --git a/script-beta/core/code-action.lua b/script-beta/core/code-action.lua
index 86bd520e..8bba07d4 100644
--- a/script-beta/core/code-action.lua
+++ b/script-beta/core/code-action.lua
@@ -120,14 +120,60 @@ local function solveSyntaxByChangeVersion(err, results)
     end
 end
 
+local function solveSyntaxByAddDoEnd(uri, err, results)
+    local text   = files.getText(uri)
+    local lines  = files.getLines(uri)
+    results[#results+1] = {
+        title = lang.script.ACTION_ADD_DO_END,
+        kind = 'quickfix',
+        edit = {
+            changes = {
+                [uri] = {
+                    {
+                        range   = define.range(lines, text, err.start, err.finish),
+                        newText = ('do %s end'):format(text:sub(err.start, err.finish)),
+                    },
+                }
+            }
+        }
+    }
+end
+
+local function solveSyntaxByFix(uri, err, results)
+    local text    = files.getText(uri)
+    local lines   = files.getLines(uri)
+    local changes = {}
+    for _, fix in ipairs(err.fix) do
+        changes[#changes+1] = {
+            range = define.range(lines, text, fix.start, fix.finish),
+            newText = fix.text,
+        }
+    end
+    results[#results+1] = {
+        title = lang.script['ACTION_' .. err.fix.title],
+        kind  = 'quickfix',
+        edit = {
+            changes = {
+                [uri] = changes,
+            }
+        }
+    }
+end
+
 local function solveSyntax(uri, diag, results)
-    local err    = findSyntax(uri, diag)
+    local err = findSyntax(uri, diag)
     if not err then
         return
     end
     if err.version then
         solveSyntaxByChangeVersion(err, results)
     end
+    if err.type == 'ACTION_AFTER_BREAK' or err.type == 'ACTION_AFTER_RETURN' then
+        solveSyntaxByAddDoEnd(uri, err, results)
+    end
+    if err.fix then
+        solveSyntaxByFix(uri, err, results)
+    end
 end
 
 local function solveDiagnostic(uri, diag, results)
diff --git a/script-beta/parser/ast.lua b/script-beta/parser/ast.lua
index 2e566047..bdf15508 100644
--- a/script-beta/parser/ast.lua
+++ b/script-beta/parser/ast.lua
@@ -1737,8 +1737,8 @@ end
 
 local function close()
     State     = nil
-    PushError = function () end
-    PushDiag  = function () end
+    PushError = function (_) end
+    PushDiag  = function (_) end
 end
 
 return {
diff --git a/script-beta/parser/guide.lua b/script-beta/parser/guide.lua
index b69c4f75..f066d925 100644
--- a/script-beta/parser/guide.lua
+++ b/script-beta/parser/guide.lua
@@ -922,6 +922,9 @@ local function buildSimpleList(obj, max)
         end
         while cur.type == 'paren' do
             cur = cur.exp
+            if not cur then
+                return nil
+            end
         end
         if cur.type == 'setfield'
         or cur.type == 'getfield'
@@ -1137,6 +1140,9 @@ end
 function m.getObjectValue(obj)
     while obj.type == 'paren' do
         obj = obj.exp
+        if not obj then
+            return nil
+        end
     end
     if obj.library then
         return nil
@@ -2890,6 +2896,9 @@ end
 function m.searchInfer(status, obj)
     while obj.type == 'paren' do
         obj = obj.exp
+        if not obj then
+            return
+        end
     end
     while true do
         local value = m.getObjectValue(obj)
diff --git a/script-beta/provider/diagnostic.lua b/script-beta/provider/diagnostic.lua
index 48d0409d..89b70061 100644
--- a/script-beta/provider/diagnostic.lua
+++ b/script-beta/provider/diagnostic.lua
@@ -50,6 +50,7 @@ local function buildSyntaxError(uri, err)
     end
 
     return {
+        code     = err.type:lower():gsub('_', '-'),
         range    = define.range(lines, text, err.start, err.finish),
         severity = define.DiagnosticSeverity.Error,
         source   = lang.script.DIAG_SYNTAX_CHECK,
diff --git a/script-beta/vm/eachField.lua b/script-beta/vm/eachField.lua
index f4c2963a..d724f56d 100644
--- a/script-beta/vm/eachField.lua
+++ b/script-beta/vm/eachField.lua
@@ -26,6 +26,9 @@ local function eachField(source)
 
     while source.type == 'paren' do
         source = source.exp
+        if not source then
+            return
+        end
     end
 
     await.delay()