[Libguestfs] [PATCH 3/3] fish: improve the command error messages

[Richard W.M. Jones]

On Thu, Dec 05, 2013 at 04:30:06PM +0100, Pino Toscano wrote:
> - when a command needs no parameters, tell that explicitly instead of
>   "command should have 0 parameters"
> - use gettext's plural form when printing the number of required
>   arguments
> - improve the error message for a variable number of parameters limited
>   only in the maximum number of them, using also a plural form
> ---
>  generator/fish.ml | 20 ++++++++++++++++----
>  1 file changed, 16 insertions(+), 4 deletions(-)
> 
> diff --git a/generator/fish.ml b/generator/fish.ml
> index 65f1acb..da0584b 100644
> --- a/generator/fish.ml
> +++ b/generator/fish.ml
> @@ -362,12 +362,24 @@ Guestfish will prompt for these separately."
>  
>        if argc_minimum = argc_maximum then (
>          pr "  if (argc != %d) {\n" argc_minimum;
> -        pr "    fprintf (stderr, _(\"%%s should have %%d parameter(s)\\n\"), cmd, %d);\n"
> -          argc_minimum;
> +        if argc_minimum = 0 then (
> +          pr "    fprintf (stderr, _(\"%%s should have no parameters\\n\"), cmd);\n";
> +        ) else (
> +          pr "    fprintf (stderr, ngettext(\"%%s should have %%d parameter\\n\",\n";
> +          pr "                              \"%%s should have %%d parameters\\n\",\n";
> +          pr "                              %d),\n"
> +            argc_minimum;
> +          pr "                     cmd, %d);\n"
> +            argc_minimum;
> +        )
>        ) else if argc_minimum = 0 then (
>          pr "  if (argc > %d) {\n" argc_maximum;
> -        pr "    fprintf (stderr, _(\"%%s should have %%d-%%d parameter(s)\\n\"), cmd, %d, %d);\n"
> -          argc_minimum argc_maximum;
> +        pr "    fprintf (stderr, ngettext(\"%%s should have at most %%d parameter\\n\",\n";
> +        pr "                              \"%%s should have at most %%d parameters\\n\",\n";
> +        pr "                              %d),\n"
> +          argc_maximum;
> +        pr "                     cmd, %d);\n"
> +          argc_maximum;
>        ) else (
>          pr "  if (argc < %d || argc > %d) {\n" argc_minimum argc_maximum;
>          pr "    fprintf (stderr, _(\"%%s should have %%d-%%d parameter(s)\\n\"), cmd, %d, %d);\n"
> -- 
> 1.8.3.1

ACK.

I tested this with various combinations of commands:

$ ./run ./fish/guestfish version foo
version should have no parameters
type 'help version' for help on version
$ ./run ./fish/guestfish set-qemu foo bar
set-qemu should have 1 parameter
type 'help set-qemu' for help on set-qemu
$ ./run ./fish/guestfish set-qemu foo bar baz
set-qemu should have 1 parameter
type 'help set-qemu' for help on set-qemu
$ ./run ./fish/guestfish lvcreate foo
lvcreate should have 3 parameters
type 'help lvcreate' for help on lvcreate
$ ./run ./fish/guestfish umount-local foo bar
umount-local should have at most 1 parameter
type 'help umount-local' for help on umount-local

[Apparently only umount-local uses the argc > argc_maximum case]

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Fedora Windows cross-compiler. Compile Windows programs, test, and
build Windows installers. Over 100 libraries supported.
http://fedoraproject.org/wiki/MinGW