[100496] trunk/dports/math/slepc/Portfile

[Ryan Schmidt]

On Dec 14, 2012, at 08:23, mmoll at macports.org wrote:

> Revision: 100496
>          https://trac.macports.org/changeset/100496
> Author:   mmoll at macports.org
> Date:     2012-12-14 06:23:42 -0800 (Fri, 14 Dec 2012)
> Log Message:
> -----------
> math/slepc: version bump, use conflicts_build port group, simplify check for fortran lib
> 
> Modified Paths:
> --------------
>    trunk/dports/math/slepc/Portfile


> variant arpack description {compile with ARPACK support} {
>     pre-fetch {
>         if {![file exists ${prefix}/lib/libparpack.a]} {
> -            return -code error "Please install the openmpi variant of arpack first."
> +            ui_error "Please install the openmpi or mpich2 variant of arpack first."
>         }
>     }

Note that while "ui_error" prints the error message to the screen, it does not end processing the port. If you want the port to exit here, which I think you do, then you need "return -code error" like you had before.

We also have the active_variants 1.1 portgroup but I'm not sure if it has provisions for requiring either/or variants. I think it's just designed to unconditionally require a variant.


>     # This is a rather fragile way to figure out where the fortran library can be
>     # found that is needed to link against libparpack.a:
> -    if {[file exists ${prefix}/lib/gcc46]} {
> -        set fortrandir ${prefix}/lib/gcc46
> -    } else {
> -        if {[file exists ${prefix}/lib/gcc45]} {
> -            set fortrandir ${prefix}/lib/gcc45
> -        } else {
> -            if {[file exists ${prefix}/lib/gcc44]} {
> -                set fortrandir ${prefix}/lib/gcc44
> -            } else {
> -                if {[file exists ${prefix}/lib/gcc43]} {
> -                    set fortrandir ${prefix}/lib/gcc43
> -                } else {
> -                    if {[file exists ${prefix}/lib/gcc42]} {
> -                        set fortrandir ${prefix}/lib/gcc42
> -                    } else {
> -                        if {[file exists ${prefix}/lib/g95]} {
> -                            set fortrandir ${prefix}/lib/g95
> -                        } else {
> -                            return -code error "Please install a fortran compiler by installing one of the following ports: gcc42, gcc43, gcc44, gcc45, gcc46, or g95."
> -                        }
> -                    }
> -                }
> -            }
> +    set fortrandirs {g95 gcc42 gcc43 gcc44 gcc45 gcc46 gcc47 gcc48}
> +    set fortrandir ""
> +    foreach dir ${fortrandirs} {
> +        if {[file exists ${prefix}/lib/${dir}]} {
> +            set fortrandir ${prefix}/lib/${dir}
>         }
>     }
> +    if {${fortrandir} == ""} {
> +        ui_error "Please install a fortran compiler by installing one of the following ports:\n\tgcc42, gcc43, gcc44, gcc45, gcc46, gcc47, gcc48, or g95."
> +    }

Same here: "return -code error" should be used instead of—or in addition to—"ui_error". I typically write only short sentence fragments with "return -code error" (since MacPorts will take up half the line with its own output), and if I have more to say, I write some complete sentences in "ui_error" calls before that.

For example from the conflicts_build portgroup:


            if {${subport} == ${badport}} {
                ui_error "${subport} cannot be built while another version of ${badport} is active."
                ui_error "Please deactivate the existing copy of ${badport} and try again."
            } else {
                ui_error "${subport} cannot be built while ${badport} is active."
                ui_error "Please deactivate ${badport} and try again."
                ui_error "You can reactivate ${badport} again later."
            }
            return -code error "${badport} is active"