buffer: fix copying setl options for buffer currently displayed in another window

vim-patch:8.0.1836: buffer-local window options may not be recent
Problem:    Buffer-local window options may not be recent if the buffer is
            still open in another window.
Solution:   Copy the options from the window instead of the outdated window
            options. (Bjorn Linse, closes vim/vim#2336)
https://github.com/vim/vim/commit/25782a7ff4755daf16c2e1cb5e5f826b13b672ce

1 files changed, 52 insertions, 0 deletions

diff --git a/src/nvim/testdir/test_options.vim b/src/nvim/testdir/test_options.vim
index d9cd5fd583..f0aec42ae1 100644
--- a/src/nvim/testdir/test_options.vim
+++ b/src/nvim/testdir/test_options.vim
@@ -287,3 +287,55 @@ func Test_set_indentexpr()
   call assert_equal('', &indentexpr)
   bwipe!
 endfunc
+
+func Test_copy_winopt()
+  set hidden
+
+  " Test copy option from current buffer in window
+  split
+  enew
+  setlocal numberwidth=5
+  wincmd w
+  call assert_equal(4,&numberwidth)
+  bnext
+  call assert_equal(5,&numberwidth)
+  bw!
+  call assert_equal(4,&numberwidth)
+
+  " Test copy value from window that used to be display the buffer
+  split
+  enew
+  setlocal numberwidth=6
+  bnext
+  wincmd w
+  call assert_equal(4,&numberwidth)
+  bnext
+  call assert_equal(6,&numberwidth)
+  bw!
+
+  " Test that if buffer is current, don't use the stale cached value
+  " from the last time the buffer was displayed.
+  split
+  enew
+  setlocal numberwidth=7
+  bnext
+  bnext
+  setlocal numberwidth=8
+  wincmd w
+  call assert_equal(4,&numberwidth)
+  bnext
+  call assert_equal(8,&numberwidth)
+  bw!
+
+  " Test value is not copied if window already has seen the buffer
+  enew
+  split
+  setlocal numberwidth=9
+  bnext
+  setlocal numberwidth=10
+  wincmd w
+  call assert_equal(4,&numberwidth)
+  bnext
+  call assert_equal(4,&numberwidth)
+  bw!
+endfunc