[RFAv7 1/3] default-args: allow to define default arguments for aliases

[Simon Marchi]

Some random comments I noted before I thought about the "set default-args"
problem which I talked about in my response to [0/3].

I got:

Applying: default-args: allow to define default arguments for aliases
.git/rebase-apply/patch:680: trailing whitespace.
   if DEFAULT_ARGS is not null, *DEFAULT_ARGS is set to the found command
warning: 1 line adds whitespace errors.


> @@ -1046,6 +1046,32 @@ fput_command_name_styled (struct cmd_list_element *c, struct ui_file *stream)
>     If one or more names are printed, POSTFIX is printed after the last name.
>  */
>  
> +/* Print the definition of alias C using title style for alias
> +   and aliased command.  */

The comment just above this (we see the end in this hunk) should stay with function fput_command_names_styled.

> +
> +static void
> +fput_alias_definition_styled (struct cmd_list_element *c, struct ui_file *stream)
> +{
> +  gdb_assert (c->cmd_pointer != nullptr);
> +  fputs_filtered ("  alias ", stream);
> +  fput_command_name_styled (c, stream);
> +  fprintf_filtered (stream, " = ");
> +  fput_command_name_styled (c->cmd_pointer, stream);
> +  fprintf_filtered (stream, " %s\n", c->default_args.c_str ());
> +}
> +
> +/* Print the definition of the aliases of CMD that have default args.  */
> +
> +static void
> +fput_aliases_definition_styled (struct cmd_list_element *cmd, struct ui_file *stream)
> +{
> +  if (cmd->aliases != nullptr)
> +    for (cmd_list_element *iter = cmd->aliases; iter; iter = iter->alias_chain)
> +      if (!iter->default_args.empty ())
> +	fput_alias_definition_styled (iter, stream);

When we have nested control structures, the GNU coding style recommends to
use braces for the outer ones:

https://www.gnu.org/prep/standards/html_node/Syntactic-Conventions.html#Syntactic-Conventions

I'd suggest following it, so:

if (...)
  {
    for (...)
      {
        if (...)
          ..
      }
  }

> @@ -1205,9 +1240,43 @@ help_cmd (const char *command, struct ui_file *stream)
>    /* If the user asked 'help somecommand' and there is no alias,
>       the false indicates to not output the (single) command name.  */
>    fput_command_names_styled (c, false, "\n", stream);
> +  fput_aliases_definition_styled (c, stream);
>    fputs_filtered (c->doc, stream);
>    fputs_filtered ("\n", stream);
>  
> +  if (c->func != nullptr)
> +    {
> +      /* Print the default args of the command if it has some.  Use the
> +	 lookup_cmd_composition result to find if help was requested for an
> +	 alias.  In this case, rather print the alias default_args.  */
> +
> +      const char *name;
> +      std::string default_args;

Use pointer to std::string to avoid an unnecessary copy?

Simon