patch 9.1.0651: ex: trailing dot is optional for :g and :insert/:append

Problem:  ex: trailing dot is optional for :g and :insert/:append
Solution: don't break out early, when the next command is empty.
          (Mohamed Akram)

The terminating period is optional for the last command in a global
command list.

closes: #15407

Signed-off-by: Mohamed Akram <mohd.akram@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/ex_cmds.c

@@ -3370,7 +3370,7 @@ ex_append(exarg_T *eap)
 	{
 	    // No getline() function, use the lines that follow. This ends
 	    // when there is no more.
-	    if (eap->nextcmd == NULL || *eap->nextcmd == NUL)
+	    if (eap->nextcmd == NULL)
 		break;
 	    p = vim_strchr(eap->nextcmd, NL);
 	    if (p == NULL)
@@ -3378,6 +3378,8 @@ ex_append(exarg_T *eap)
 	    theline = vim_strnsave(eap->nextcmd, p - eap->nextcmd);
 	    if (*p != NUL)
 		++p;
+	    else
+		p = NULL;
 	    eap->nextcmd = p;
 	}
 	else

src/testdir/test_ex_mode.vim

@@ -378,4 +378,13 @@ func Test_insert_after_trailing_bar()
 " Test inserting text after the trailing bar
 func Test_insert_after_trailing_bar()
   new
+  call feedkeys("Qi|\nfoo\n.\na|bar\nbar\n.\nc|baz\n.", "xt")
+  call assert_equal(['', 'foo', 'bar', 'baz'], getline(1, '$'))
+  bwipe!
+endfunc
+
+" Test global insert of a newline without terminating period
+func Test_global_insert_newline()
+  new
+  call setline(1, ['foo'])
   call feedkeys("Qg/foo/i\\\n", "xt")

src/version.c

@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    651,
 /**/
     650,
 /**/