patch 8.0.1721: no test for using the 'termsize' option
Problem: No test for using the 'termsize' option.
Solution: Add a test.
diff --git a/src/testdir/test_terminal.vim b/src/testdir/test_terminal.vim
index 5f330f7..eb22b0f 100644
--- a/src/testdir/test_terminal.vim
+++ b/src/testdir/test_terminal.vim
@@ -1356,3 +1356,36 @@
call term_wait(buf)
exe buf . 'bwipe'
endfunc
+
+func Test_terminal_termsize_option()
+ if !CanRunVimInTerminal()
+ return
+ endif
+ set termsize=6x40
+ let text = []
+ for n in range(10)
+ call add(text, repeat(n, 50))
+ endfor
+ call writefile(text, 'Xwinsize')
+ let buf = RunVimInTerminal('Xwinsize', {})
+ let win = bufwinid(buf)
+ call assert_equal([6, 40], term_getsize(buf))
+ call assert_equal(6, winheight(win))
+ call assert_equal(40, winwidth(win))
+
+ " resizing the window doesn't resize the terminal.
+ resize 10
+ vertical resize 60
+ call assert_equal([6, 40], term_getsize(buf))
+ call assert_equal(10, winheight(win))
+ call assert_equal(60, winwidth(win))
+
+ call StopVimInTerminal(buf)
+ call delete('Xwinsize')
+
+ call assert_fails('set termsize=40', 'E474')
+ call assert_fails('set termsize=10+40', 'E474')
+ call assert_fails('set termsize=abc', 'E474')
+
+ set termsize=
+endfunc