From 8154c77bef1327aca76b83a1ec5177510f6b4b7b Mon Sep 17 00:00:00 2001
From: erw7 <erw7.github@gmail.com>
Date: Thu, 1 Oct 2020 16:53:21 +0900
Subject: screen.c: fix buffer overflow due to folding

fixes #12988.
---
 test/functional/ui/fold_spec.lua | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

(limited to 'test/functional/ui/fold_spec.lua')

diff --git a/test/functional/ui/fold_spec.lua b/test/functional/ui/fold_spec.lua
index fe67b9f6b0..9877f30206 100644
--- a/test/functional/ui/fold_spec.lua
+++ b/test/functional/ui/fold_spec.lua
@@ -6,6 +6,8 @@ local feed_command = helpers.feed_command
 local insert = helpers.insert
 local funcs = helpers.funcs
 local meths = helpers.meths
+local source = helpers.source
+local assert_alive = helpers.assert_alive
 
 describe("folded lines", function()
   local screen
@@ -357,4 +359,26 @@ describe("folded lines", function()
                                                  |
     ]]}
   end)
+
+  it('does not crash when foldtext is longer than columns #12988', function()
+    source([[
+      function! MyFoldText() abort
+        return repeat('-', &columns + 100)
+      endfunction
+    ]])
+    command('set foldtext=MyFoldText()')
+    feed("i<cr><esc>")
+    feed("vkzf")
+    screen:expect{grid=[[
+    {5:^---------------------------------------------}|
+    {1:~                                            }|
+    {1:~                                            }|
+    {1:~                                            }|
+    {1:~                                            }|
+    {1:~                                            }|
+    {1:~                                            }|
+                                                 |
+    ]]}
+    assert_alive()
+  end)
 end)
-- 
cgit