Re: [FYI] {maint} tests/README: update obsoleted advice

[Ralf Wildenhues]

* Stefano Lattarini wrote on Fri, May 20, 2011 at 10:21:09PM CEST:
> * tests/README (Section "Writing test cases" subsection "Do"):
> Do not suggest to use the `*-p.test' pattern for the names of
> hand-written tests which use the `parallel-tests' Automake option.
> Not only is this not respected by the existing tests, but it is
> more likely to cause conflicts with auto-generated tests.
> So, suggest to *avoid* using the `*-p.test' pattern in names
> of hand-written tests instead.
> (Section "Writing test cases" subsection "Do not"):  When
> suggesting not to override Makefile variables using command
> line arguments, do not use the badly outdated variables `U'
> and 'ANSI2KNR' in the example; instead, use the more common
> and typical `DESTDIR'.

Actually, this change has a slight technical error: when some variable
is never initialized in the Makefile, -e is not necessary in order to
override it.  DESTDIR is such a variable: we ensure that we do not ever
initialize it.  And as such, it is quite portable to use
  make DESTDIR=/foo/bar install

and in fact, quite widely used.

Can we use some other variable as example?  How about prefix?

Cheers,
Ralf

> --- a/tests/README
> +++ b/tests/README
> @@ -107,8 +107,8 @@ Do
>  
>    For tests that use the `parallel-tests' Automake option, set the shell
>    variable `parallel_tests' to "yes" before including ./defs.  Also,
> -  use for them a name that ends in `-p.test' and does not clash with any
> -  generated tests in the suite.
> +  do not use for them a name that ends in `-p.test', since that would
> +  risk to clash with automatically-generated tests.
>  
>    ./defs sets a skeleton configure.in.  If possible, append to this
>    file.  In some cases you'll have to overwrite it, but this should
> @@ -177,12 +177,12 @@ Do not
>    reason, but at least it makes sure the original error is still
>    here.)
>  
> -  Do not override Makefile variables using make arguments, as in
> -    $MAKE ANSI2KNR=./ansi2knr U=_ all
> -  this is not portable for recursive targets (targets that
> -  call a sub-make may not pass `ANSI2KNR=./ansi2knr U=_' along).
> -  Use the following instead.
> -    ANSI2KNR=./ansi2knr U=_ $MAKE -e all
> +  Do not override Makefile variables using make arguments, as in e.g.:
> +    $MAKE DESTDIR=/foo/bar install
> +  This is not portable for recursive targets (targets that call a
> +  sub-make may not pass `DESTDIR=/foo/bar' along).  Use the following
> +  instead:
> +    DESTDIR=/foo/bar $MAKE -e install
>  
>    Do not send a test case without signing a copyright disclaimer.
>    See http://sources.redhat.com/automake/contribute.html or