patch 8.0.0042
Problem:    When using Insert mode completion with 'completeopt' containing
            "noinsert" change is not saved for undo.  (Tommy Allen)
Solution:   Call stop_arrow() before inserting for pressing Enter.
diff --git a/src/edit.c b/src/edit.c
index 53b43c4..776a420 100644
--- a/src/edit.c
+++ b/src/edit.c
@@ -857,8 +857,9 @@
 
 		/* Pressing CTRL-Y selects the current match.  When
 		 * compl_enter_selects is set the Enter key does the same. */
-		if (c == Ctrl_Y || (compl_enter_selects
-				   && (c == CAR || c == K_KENTER || c == NL)))
+		if ((c == Ctrl_Y || (compl_enter_selects
+				    && (c == CAR || c == K_KENTER || c == NL)))
+			&& stop_arrow() == OK)
 		{
 		    ins_compl_delete();
 		    ins_compl_insert(FALSE);
diff --git a/src/testdir/test_popup.vim b/src/testdir/test_popup.vim
index 38459b3..d037b7a 100644
--- a/src/testdir/test_popup.vim
+++ b/src/testdir/test_popup.vim
@@ -420,6 +420,13 @@
   call feedkeys("u", 'xt')
   call assert_equal('', getline(2))
 
+  call feedkeys("ibbb\<Esc>0", 'xt')
+  call assert_equal('bbb', getline(2))
+  call feedkeys("A\<Right>\<Down>\<CR>\<Esc>", 'xt')
+  call assert_equal('January', getline(2))
+  call feedkeys("u", 'xt')
+  call assert_equal('bbb', getline(2))
+
   iunmap <Right>
   set completeopt&
   q!
diff --git a/src/version.c b/src/version.c
index 4902d69..3a2b1a5 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    42,
+/**/
     41,
 /**/
     40,