patch 8.0.1637: no test for term_dumpdiff() options argument

Problem:    No test for term_dumpdiff() options argument.
Solution:   Add a test.

src/testdir/test_terminal.vim

@@ -995,3 +995,31 @@ func Test_terminal_dumpdiff()
   call assert_equal('           bbbbbbbbbbbbbbbbbb ', getline(26)[0:29])
   quit
 endfunc
+
+func Test_terminal_dumpdiff_options()
+  set laststatus=0
+  call assert_equal(1, winnr('$'))
+  let height = winheight(0)
+  call term_dumpdiff('dumps/Test_popup_command_01.dump', 'dumps/Test_popup_command_02.dump', {'vertical': 1, 'term_cols': 33})
+  call assert_equal(2, winnr('$'))
+  call assert_equal(height, winheight(winnr()))
+  call assert_equal(33, winwidth(winnr()))
+  call assert_equal('dump diff dumps/Test_popup_command_01.dump', bufname('%'))
+  quit
+
+  call assert_equal(1, winnr('$'))
+  let width = winwidth(0)
+  call term_dumpdiff('dumps/Test_popup_command_01.dump', 'dumps/Test_popup_command_02.dump', {'vertical': 0, 'term_rows': 13, 'term_name': 'something else'})
+  call assert_equal(2, winnr('$'))
+  call assert_equal(width, winwidth(winnr()))
+  call assert_equal(13, winheight(winnr()))
+  call assert_equal('something else', bufname('%'))
+  quit
+
+  call assert_equal(1, winnr('$'))
+  call term_dumpdiff('dumps/Test_popup_command_01.dump', 'dumps/Test_popup_command_02.dump', {'curwin': 1})
+  call assert_equal(1, winnr('$'))
+  bwipe
+
+  set laststatus&
+endfunc

src/version.c

@@ -766,6 +766,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1637,
 /**/
     1636,
 /**/