Re: [Qemu-devel] [PATCH 01/74] tests: acpi: print ASL diff in verbose mode

[Michael S. Tsirkin]

On Tue, Dec 22, 2015 at 06:22:08PM +0100, Igor Mammedov wrote:
> On Tue, 22 Dec 2015 18:59:30 +0200
> "Michael S. Tsirkin" <address@hidden> wrote:
> 
> > On Tue, Dec 22, 2015 at 04:54:06PM +0100, Igor Mammedov wrote:
> > > On Tue, 22 Dec 2015 17:28:42 +0200
> > > "Michael S. Tsirkin" <address@hidden> wrote:
> > > 
> > > > On Thu, Dec 10, 2015 at 12:40:55AM +0100, Igor Mammedov wrote:
> > > > > Signed-off-by: Igor Mammedov <address@hidden>
> > > > > ---
> > > > >  tests/bios-tables-test.c | 7 +++++++
> > > > >  1 file changed, 7 insertions(+)
> > > > > 
> > > > > diff --git a/tests/bios-tables-test.c b/tests/bios-tables-test.c
> > > > > index 6d37332..50678b5 100644
> > > > > --- a/tests/bios-tables-test.c
> > > > > +++ b/tests/bios-tables-test.c
> > > > > @@ -580,6 +580,13 @@ static void test_acpi_asl(test_data *data)
> > > > >                          (gchar *)&signature,
> > > > >                          sdt->asl_file, sdt->aml_file,
> > > > >                          exp_sdt->asl_file, exp_sdt->aml_file);
> > > > > +                if (getenv("V")) {
> > > > 
> > > > How do you test? make check V=1?
> > > yep
> > >  make V=1 check
> > > 
> > > > 
> > > > > +                    int ret G_GNUC_UNUSED;
> > > > > +                    char *diff = g_strdup_printf("git diff 
> > > > > --exit-code %s %s",
> > > > > +                        exp_sdt->asl_file, sdt->asl_file);
> > > > 
> > > > This assumes running under git which is generally wrong e.g.
> > > > people build from tarballs.
> > > > git is also not a build dependency.
> > > usually only developers use V=1 as they care about verbose output
> > > and they probably use/have git so it doesn't have to builddep,
> > > if they don't they won't get any useful output here.
> > > 
> > > my choice of 'git diff' was dictated by the fact that
> > > it produces nice colored diff of ASL while usual diff doesn't.
> > > And that helps a lot (to me) as that diff is intended
> > > for human consumption.
> > 
> > I just do vimdiff on the two files it prints.
> > Not sure all this is worth it.
> yep, it's something that I was doing manually as well,
> but after 50th or so times it was taking too much time,
> hence a patch that saves my and hopefully others time.
> Alternative solution if V=1:
>  1. use variable to specify diff command
>  2. if variable is not defined, print warning to set it
> 
> that way user will be informed about diff option when
> 'make V=1 check' is run and diff is not specified.

OK.

> > 
> > > > 
> > > > 
> > > > > +                    ret = system(diff) ;
> > > > > +                    g_free(diff);
> > > > > +                }
> > > > >            }
> > > > >          }
> > > > >          g_string_free(asl, true);
> > > > > -- 
> > > > > 1.8.3.1
> > > > >