patch 8.0.1237: ":set scroll&" often gives an error
Problem: ":set scroll&" often gives an error.
Solution: Don't use a fixed default value, use half the window height. Add a
test. (Ozaki Kiichi, closes #2104)
diff --git a/src/testdir/test_scroll_opt.vim b/src/testdir/test_scroll_opt.vim
new file mode 100644
index 0000000..77920eb
--- /dev/null
+++ b/src/testdir/test_scroll_opt.vim
@@ -0,0 +1,36 @@
+" Test for reset 'scroll'
+"
+
+func Test_reset_scroll()
+ let scr = &l:scroll
+
+ setlocal scroll=1
+ setlocal scroll&
+ call assert_equal(scr, &l:scroll)
+
+ setlocal scroll=1
+ setlocal scroll=0
+ call assert_equal(scr, &l:scroll)
+
+ try
+ execute 'setlocal scroll=' . (winheight(0) + 1)
+ " not reached
+ call assert_false(1)
+ catch
+ call assert_exception('E49:')
+ endtry
+
+ split
+
+ let scr = &l:scroll
+
+ setlocal scroll=1
+ setlocal scroll&
+ call assert_equal(scr, &l:scroll)
+
+ setlocal scroll=1
+ setlocal scroll=0
+ call assert_equal(scr, &l:scroll)
+
+ quit!
+endfunc