FreshPorts element strip repo head /ports/head /ports/branches/2020Q4

StripLeadingPrefix

sub StripLeadingPrefix {
    # take an element name, and remove the leading /ports/head or /ports/branches/foo from the path name
    # for example: /ports/head/lang/yap/Makefile
    #              /ports/head/lang/yap/files/patch-Makefile.in
    #             /ports/head/lang/yap/pkg-descr


    # split the incoming path up by /
    # This will have a leading /, so we wind up with
    #
    # $VAR1 = '';
    # $VAR2 = 'ports';
    # $VAR3 = 'head';
    #
    # for example.
    #
    my @path = split '/', shift;

    # empty the first three elements, and that returns the first element,
    # which if is 'branches', remove that element too.
    splice(@path, 0, 3) eq "branches" and shift @path;

    # add a / to the front of the path
    join '/', @path;
}