vim-patch:8.1.0497: :%diffput changes order of lines

Problem:    :%diffput changes order of lines. (Markus Braun)
Solution:   Do adjust marks when using internal diff.

5f57bdcab7

src/nvim/diff.c

@@ -271,9 +271,9 @@ static void diff_mark_adjust_tp(tabpage_T *tp, int idx, linenr_T line1,
     // Will update diffs before redrawing.  Set _invalid to update the
     // diffs themselves, set _update to also update folds properly just
     // before redrawing.
+    // Do update marks here, it is needed for :%diffput.
     tp->tp_diff_invalid = true;
     tp->tp_diff_update = true;
-    return;
   }
 
   int inserted;
@@ -2742,7 +2742,7 @@ theend:
     ex_diffupdate(NULL);
   }
 
-  // Check that the cursor is on a valid character and update it's
+  // Check that the cursor is on a valid character and update its
   // position.  When there were filler lines the topline has become
   // invalid.
   check_cursor();

src/nvim/testdir/test_diffmode.vim

@@ -219,6 +219,26 @@ func Test_diffget_diffput()
   %bwipe!
 endfunc
 
+" Test putting two changes from one buffer to another
+func Test_diffput_two()
+  new a
+  let win_a = win_getid()
+  call setline(1, range(1, 10))
+  diffthis
+  new b
+  let win_b = win_getid()
+  call setline(1, range(1, 10))
+  8del
+  5del
+  diffthis
+  call win_gotoid(win_a)
+  %diffput
+  call win_gotoid(win_b)
+  call assert_equal(map(range(1, 10), 'string(v:val)'), getline(1, '$'))
+  bwipe! a
+  bwipe! b
+endfunc
+
 func Test_dp_do_buffer()
   e! one
   let bn1=bufnr('%')