patch 9.1.1437: MS-Windows: internal compile error in uc_list()

Problem:  MS-Windows: internal compile error in uc_list() with VS 17.14
          (ibear)
Solution: refactor code slightly (Mike Williams)

fixes: #17402
closes: #17464

Signed-off-by: Mike Williams <mrmrdubya@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/testdir/test_usercommands.vim

@@ -965,5 +965,24 @@ func Test_comclear_while_listing()
   call StopVimInTerminal(buf)
 endfunc
 
+" Test for listing user commands.
+func Test_command_list_0()
+  " Check space padding of attribute and name in command list
+  set vbs&
+  command! ShortCommand echo "ShortCommand"
+  command! VeryMuchLongerCommand echo "VeryMuchLongerCommand"
+
+  redi @"> | com | redi END
+  pu
+
+  let bl = matchbufline(bufnr('%'), "^    ShortCommand      0", 1, '$')
+  call assert_false(bl == [])
+  let bl = matchbufline(bufnr('%'), "^    VeryMuchLongerCommand 0", 1, '$')
+  call assert_false(bl == [])
+
+  bwipe!
+  delcommand ShortCommand
+  delcommand VeryMuchLongerCommand
+endfunc
 
 " vim: shiftwidth=2 sts=2 expandtab

src/usercmd.c

@@ -600,17 +600,21 @@ uc_list(char_u *name, size_t name_len)
 		msg_putchar('|');
 		--len;
 	    }
-	    while (len-- > 0)
+	    if (len != 0)
-		msg_putchar(' ');
+		msg_puts(&"    "[4 - len]);
 
 	    msg_outtrans_attr(cmd->uc_name, HL_ATTR(HLF_D));
 	    len = (int)cmd->uc_namelen + 4;
 
-	    do
+	    if (len < 21)
 	    {
-		msg_putchar(' ');
+		// Field padding spaces   12345678901234567
-		++len;
+		static char spaces[18] = "                 ";
-	    } while (len < 22);
+		msg_puts(&spaces[len - 4]);
+		len = 21;
+	    }
+	    msg_putchar(' ');
+	    ++len;
 
 	    // "over" is how much longer the name is than the column width for
 	    // the name, we'll try to align what comes after.

src/version.c

@@ -709,6 +709,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1437,
 /**/
     1436,
 /**/