#
# $Id: NoBreakpoints.pm 159 2004-12-31 02:57:11Z james $
#

=head1 NAME

Test::NoBreakpoints - test that files do not contain soft breakpoints

=head1 SYNOPSIS

 use Test::NoBreakpoints;
 plan tests => $num_tests;
 no_brkpts_ok( $file, 'Contains no soft breakpoints' );

Module authors can include the following in a t/nobreakpoints.t file to add
such checking to a module distribution:

  use Test::More;
  eval "use Test::NoBreakpoints 0.10";
  plan skip_all => "Test::NoBreakpoints 0.10 required for testing" if $@;
  all_files_no_brkpts_ok();

=head1 DESCRIPTION

I love soft breakpoints (C<$DB::single = 1>) in the Perl debugger. 
Unfortunately, I have a habit of putting them in my code during development
and forgetting to take them out before I upload it to CPAN, necessitating a
hasty fix/package/bundle cycle followed by much cursing.

Test::NoBreakpoints checks that files contain neither the string
C<$DB::single = 1> nor C<$DB::signal = 1>.  By adding such a test to all my
modules, I swear less and presumably lighten the load on the CPAN in some
small way.

=cut

package Test::NoBreakpoints;

use strict;

use File::Spec;
use File::Find;
use Test::Builder;

require Exporter;
use vars qw($VERSION @ISA @EXPORT @EXPORT_OK %EXPORT_TAGS);

$VERSION   = '0.12';
@ISA       = 'Exporter';
@EXPORT    = qw|all_files_no_brkpts_ok no_brkpts_ok|;
@EXPORT_OK = qw|all_perl_files|;
%EXPORT_TAGS = (
    all => [ @EXPORT, @EXPORT_OK ],
);

# get a Test singleton to use
my $Test = Test::Builder->new;

# a regular expression to find soft breakpoints
my $brkpt_rx = qr/
    (                   # match it
        \$DB            # The DB package
        (?:::|')        # Perl 4 or 5 package seperator
        si(?:ngle|gnal) # signal or single
        \s*=\s*         # an equal with optional whitespace
        [1-9]           # a digit other than zero
                        # (am I being stupid here?  Is there
    )                   #  no easier way to say that?)
/x;

# check that there are no breakpoints in a file
sub no_brkpts_ok($;$)
{
    
    my($file, $name) = @_;
    $name ||= "no breakpoint test of $file";
    
    # slurp in the file
    my $fh;
    unless( open($fh, $file) ) {
        $Test->ok(0, $name);
        $Test->diag("could not open $file: $!");
        return;
    }
    my $text = do { local( $/ ) ; <$fh> } ;
    close($fh);
    
    # check the file against our regex
    my($matched) = $text =~ m/$brkpt_rx/;
    if( ! $matched ) {
        $Test->ok(1, $name);
    }
    else {
        $Test->ok(0, $name);
        $Test->diag("breakpoint found in $file: $matched");
    }
    
    return $matched ? 0 : 1;
    
}

# find all perl files in a given directory
# graciously borrwed from Test::Pod::all_pod_files by
# Andy Lester / brian d foy
sub all_perl_files
{

    my @queue = @_ ? @_ : _starting_points();
    my @files = ();

    while ( @queue ) {
        my $file = shift @queue;
        if ( -d $file ) {
            local *DH;
            opendir DH, $file or next;
            my @newfiles = readdir DH;
            closedir DH;

            @newfiles = File::Spec->no_upwards( @newfiles );
            @newfiles = grep { $_ ne "CVS" && $_ ne ".svn" } @newfiles;

            push @queue, map "$file/$_", @newfiles;
        }
        if ( -f $file ) {
            push @files, $file if _is_perl( $file );
        }
    } # while

    return @files;

}

sub _starting_points {
    return 'blib' if -e 'blib';
    return 'lib';
}

sub _is_perl {
    my $file = shift;

    return 1 if $file =~ /\.PL$/;
    return 1 if $file =~ /\.p(l|m)$/;
    return 1 if $file =~ /\.t$/;

    local *FH;
    open FH, $file or return;
    my $first = <FH>;
    close FH;

    return 1 if defined $first && ($first =~ /^#!.*perl/);

    return;
}        

# run no_brkpts_ok on all files in a given directory
sub all_files_no_brkpts_ok
{

    my @files = @_ ? @_ : all_perl_files();

    my $ok = 1; # presume all succeed
    for( @files ) {
        no_brkpts_ok($_) or $ok = 0;
    }
    return $ok;
    
}

# keep require happy
1;


__END__

=head1 FUNCTIONS

Unless otherwise noted, all functions are tests built on top of
Test::Builder, so the standard admonition about having made a plan before
you run them apply.

=head2 no_brkpts_ok($file, [$description] )

Checks that $file contains no breakpoints.  If the optional $description is
not passed it defaults to "no breakpoint test of $file".

If the test fails, the line number of the file where the breakpoint was
found will be emitted.

=head2 all_perl_files( [@dirs] )

Returns a list of all F<*.pl>, F<*.pm> and F<*.t> files in the directories
listed.  If C<@dirs> is not passed, defaults to C<blib> and C<t>.

The order of the files returned is machine-dependent.  If you want them
sorted, you'll have to sort them yourself.

=head2 all_files_no_brkpts_ok( [@files] )

Checks all files that look like they contain Perl using no_brkpts_ok(). If
C<@files> is not provided, it defaults to the return of B<all_perl_files()>.

=head1 EXPORTS

By default B<all_files_no_brkpts_ok> and B<no_brkpts_ok>.

On request, B<all_perl_files>.

Everything with the tag B<:all>.

=head1 ACKNOWLEDGEMENTS

Michael Schwern for Test::Builder.

Andy Lester for Test::Pod, which is where I got the idea and borrowed the
logic of B<all_perl_files> from.

=head1 BUGS

=over 4

=item * doesn't catch some breakpoints

This is a valid breakpoint:

  package DB;
  $single = 1;
  package main;

as is this:

  my $break = \$DB::single;
  $$break = 1;

but neither are currently caught.

=back

=head1 TODO

=over 4

=item * enhance regex to find esoteric setting of breakpoints

If you have a legitimate breakpoint set that isn't caught, please send me an
example and I'll try to augment the regex to match it.

=item * only look at code rather than the entire file

This is not as easy as simply stripping out POD, because there might be
inline tests or examples that are code in there (using Test::Inline).
Granted, those should be caught when the generated .t files are themselves
tested, but I'd like to make it smarter.

=item * not use regular expressions

The ideal way to find a breakpoint would be to compile the code and then
walk the opcode tree to find places where the breakpoint is set. 
B::FindAmpersand does something similar to this to find use of the C<$&> in
regular expressions, so this is probably the direction I'm going to head in.

=back

=head1 SEE ALSO

L<Test::Builder>

L<Test::Pod>

=head1 AUTHOR

James FitzGibbon E<lt>jfitz@CPAN.orgE<gt>

=head1 COPYRIGHT

Copyright (c) 2004, James FitzGibbon.  All Rights Reserved.

This module is free software. You may use it under the same terms as perl
itself.

=cut

#
# EOF

