#! /usr/bin/env perl

# Program for testing regular expressions with perl to check that PCRE handles

# them the same. This version needs to have "use utf8" at the start for running

# the UTF-8 tests, but *not* for the other tests. The only way I've found for

# doing this is to cat this line in explicitly in the RunPerlTest script. I've

# also used this method to supply "require Encode" for the UTF-8 tests, so that

# the main test will still run where Encode is not installed.

#use utf8;

#require Encode;

# Function for turning a string into a string of printing chars.

sub pchars {

my($t) = "";

if ($utf8)

  {

  @p = unpack('U*', $_[0]);

  foreach $c (@p)

    {

    if ($c >= 32 && $c < 127) { $t .= chr $c; }

      else { $t .= sprintf("\\x{%02x}", $c);

      }

    }

  }

else

  {

  foreach $c (split(//, $_[0]))

    {

    if (ord $c >= 32 && ord $c < 127) { $t .= $c; }

      else { $t .= sprintf("\\x%02x", ord $c); }

    }

  }

$t;

}

# Read lines from named file or stdin and write to named file or stdout; lines

# consist of a regular expression, in delimiters and optionally followed by

# options, followed by a set of test data, terminated by an empty line.

# Sort out the input and output files

if (@ARGV > 0)

  {

  open(INFILE, "<$ARGV[0]") || die "Failed to open $ARGV[0]\n";

  $infile = "INFILE";

  }

else { $infile = "STDIN"; }

if (@ARGV > 1)

  {

  open(OUTFILE, ">$ARGV[1]") || die "Failed to open $ARGV[1]\n";

  $outfile = "OUTFILE";

  }

else { $outfile = "STDOUT"; }

printf($outfile "Perl $] Regular Expressions\n\n");

# Main loop

NEXT_RE:

for (;;)

  {

  printf "  re> " if $infile eq "STDIN";

  last if ! ($_ = <$infile>);

  printf $outfile "$_" if $infile ne "STDIN";

  next if ($_ =~ /^\s*$/ || $_ =~ /^< forbid/);

  $pattern = $_;

  while ($pattern !~ /^\s*(.).*\1/s)

    {

    printf "    > " if $infile eq "STDIN";

    last if ! ($_ = <$infile>);

    printf $outfile "$_" if $infile ne "STDIN";

    $pattern .= $_;

    }

  chomp($pattern);

  $pattern =~ s/\s+$//;

  # The private /+ modifier means "print $' afterwards".

  $showrest = ($pattern =~ s/\+(?=[a-zA-Z]*$)//);

  # A doubled version is used by pcretest to print remainders after captures

  $pattern =~ s/\+(?=[a-zA-Z]*$)//;

  # Remove /8 from a UTF-8 pattern.

  $utf8 = $pattern =~ s/8(?=[a-zA-Z]*$)//;

  # Remove /J from a pattern with duplicate names.

  $pattern =~ s/J(?=[a-zA-Z]*$)//;

  # Remove /K from a pattern (asks pcretest to check MARK data) */

  $pattern =~ s/K(?=[a-zA-Z]*$)//;

  # /W asks pcretest to set PCRE_UCP; change this to /u for Perl

  $pattern =~ s/W(?=[a-zA-Z]*$)/u/;

  # Remove /S or /SS from a pattern (asks pcretest to study or not to study)

  $pattern =~ s/S(?=[a-zA-Z]*$)//g;

  # Remove /Y and /O from a pattern (disable PCRE optimizations)

  $pattern =~ s/[YO](?=[a-zA-Z]*$)//;

  # Check that the pattern is valid

  eval "\$_ =~ ${pattern}";

  if ($@)

    {

    printf $outfile "Error: $@";

    if ($infile != "STDIN")

      {

      for (;;)

        {

        last if ! ($_ = <$infile>);

        last if $_ =~ /^\s*$/;

        }

      }

    next NEXT_RE;

    }

  # If the /g modifier is present, we want to put a loop round the matching;

  # otherwise just a single "if".

  $cmd = ($pattern =~ /g[a-z]*$/)? "while" : "if";

  # If the pattern is actually the null string, Perl uses the most recently

  # executed (and successfully compiled) regex is used instead. This is a

  # nasty trap for the unwary! The PCRE test suite does contain null strings

  # in places - if they are allowed through here all sorts of weird and

  # unexpected effects happen. To avoid this, we replace such patterns with

  # a non-null pattern that has the same effect.

  $pattern = "/(?#)/$2" if ($pattern =~ /^(.)\1(.*)$/);

  # Read data lines and test them

  for (;;)

    {

    printf "data> " if $infile eq "STDIN";

    last NEXT_RE if ! ($_ = <$infile>);

    chomp;

    printf $outfile "$_\n" if $infile ne "STDIN";

    s/\s+$//;  # Remove trailing space

    s/^\s+//;  # Remove leading space

    s/\\Y//g;  # Remove \Y (pcretest flag to set PCRE_NO_START_OPTIMIZE)

    last if ($_ eq "");

    $x = eval "\"$_\"";   # To get escapes processed

    # Empty array for holding results, ensure $REGERROR and $REGMARK are

    # unset, then do the matching.

    @subs = ();

    $pushes = "push \@subs,\$&;" .

         "push \@subs,\$1;" .

         "push \@subs,\$2;" .

         "push \@subs,\$3;" .

         "push \@subs,\$4;" .

         "push \@subs,\$5;" .

         "push \@subs,\$6;" .

         "push \@subs,\$7;" .

         "push \@subs,\$8;" .

         "push \@subs,\$9;" .

         "push \@subs,\$10;" .

         "push \@subs,\$11;" .

         "push \@subs,\$12;" .

         "push \@subs,\$13;" .

         "push \@subs,\$14;" .

         "push \@subs,\$15;" .

         "push \@subs,\$16;" .

         "push \@subs,\$'; }";

    undef $REGERROR;

    undef $REGMARK;

    eval "${cmd} (\$x =~ ${pattern}) {" . $pushes;

    if ($@)

      {

      printf $outfile "Error: $@\n";

      next NEXT_RE;

      }

    elsif (scalar(@subs) == 0)

      {

      printf $outfile "No match";

      if (defined $REGERROR && $REGERROR != 1)

        { printf $outfile (", mark = %s", &pchars($REGERROR)); }

      printf $outfile "\n";

      }

    else

      {

      while (scalar(@subs) != 0)

        {

        printf $outfile (" 0: %s\n", &pchars($subs[0]));

        printf $outfile (" 0+ %s\n", &pchars($subs[17])) if $showrest;

        $last_printed = 0;

        for ($i = 1; $i <= 16; $i++)

          {

          if (defined $subs[$i])

            {

            while ($last_printed++ < $i-1)

              { printf $outfile ("%2d: <unset>\n", $last_printed); }

            printf $outfile ("%2d: %s\n", $i, &pchars($subs[$i]));

            $last_printed = $i;

            }

          }

        splice(@subs, 0, 18);

        }

      # It seems that $REGMARK is not marked as UTF-8 even when use utf8 is

      # set and the input pattern was a UTF-8 string. We can, however, force

      # it to be so marked.

      if (defined $REGMARK && $REGMARK != 1)

        {

        $xx = $REGMARK;

        $xx = Encode::decode_utf8($xx) if $utf8;

        printf $outfile ("MK: %s\n", &pchars($xx));

        }

      }

    }

  }

# printf $outfile "\n";

# End