patch 8.1.0516: :move command marks buffer modified when nothing changed

Problem:    :move command marks buffer modified when nothing changed.
Solution:   Do not set 'modified'.  Add a test. (Jason Franklin)
diff --git a/src/testdir/test_alot.vim b/src/testdir/test_alot.vim
index 3a0c6e0..be66512 100644
--- a/src/testdir/test_alot.vim
+++ b/src/testdir/test_alot.vim
@@ -41,6 +41,7 @@
 source test_menu.vim
 source test_messages.vim
 source test_modeline.vim
+source test_move.vim
 source test_partial.vim
 source test_popup.vim
 source test_put.vim
diff --git a/src/testdir/test_move.vim b/src/testdir/test_move.vim
new file mode 100644
index 0000000..d774c93
--- /dev/null
+++ b/src/testdir/test_move.vim
@@ -0,0 +1,40 @@
+" Test the ":move" command.
+
+func Test_move()
+  enew!
+  call append(0, ['line 1', 'line 2', 'line 3'])
+  g /^$/ delete _
+  set nomodified
+
+  move .
+  call assert_equal(['line 1', 'line 2', 'line 3'], getline(1, 3))
+  call assert_false(&modified)
+
+  1,2move 0
+  call assert_equal(['line 1', 'line 2', 'line 3'], getline(1, 3))
+  call assert_false(&modified)
+
+  1,3move 3
+  call assert_equal(['line 1', 'line 2', 'line 3'], getline(1, 3))
+  call assert_false(&modified)
+
+  1move 2
+  call assert_equal(['line 2', 'line 1', 'line 3'], getline(1, 3))
+  call assert_true(&modified)
+  set nomodified
+
+  3move 0
+  call assert_equal(['line 3', 'line 2', 'line 1'], getline(1, 3))
+  call assert_true(&modified)
+  set nomodified
+
+  2,3move 0
+  call assert_equal(['line 2', 'line 1', 'line 3'], getline(1, 3))
+  call assert_true(&modified)
+  set nomodified
+
+  call assert_fails('1,2move 1', 'E134')
+  call assert_fails('2,3move 2', 'E134')
+
+  %bwipeout!
+endfunc