Error out immediatly when using if command without args in command list

When using "if" (or while) without args directly on gdb's command line,
you get this:

  (gdb) if
  if/while commands require arguments

When doing the same when entering a command list, you only get an error
when the command is executed, when parse_exp_in_context_1 fails to
evaluate the expression.

  (gdb) define foo
  Type commands for definition of "foo".
  End with a line saying just "end".
  >if
   >end
  >end
  (gdb) foo
  Argument required (expression to compute).

I think it would make more sense to error out when inputting the command
list directly:

  (gdb) define foo
  Type commands for definition of "foo".
  End with a line saying just "end".
  >if
  if/while commands require arguments.

The only required change is to check whether args is an empty string in
build_command_line.

gdb/ChangeLog:

	* cli/cli-script.c (build_command_line): For if/while commands,
	check whether args is empty.

gdb/testsuite/ChangeLog:

	* gdb.base/commands.exp: Call new procedure.
	(define_if_without_arg_test): New procedure.
This commit is contained in:
Simon Marchi 2017-09-04 19:13:08 +02:00
parent 6b66338c70
commit 80a65e9b8f
4 changed files with 28 additions and 1 deletions

View file

@ -147,7 +147,8 @@ build_command_line (enum command_control_type type, const char *args)
{
struct command_line *cmd;
if (args == NULL && (type == if_control || type == while_control))
if ((args == NULL || *args == '\0')
&& (type == if_control || type == while_control))
error (_("if/while commands require arguments."));
gdb_assert (args != NULL);