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#!perl
# Marpa::R3 is Copyright (C) 2017, Jeffrey Kegler.
#
# This module is free software; you can redistribute it and/or modify it
# under the same terms as Perl 5.10.1. For more details, see the full text
# of the licenses in the directory LICENSES.
#
# This program is distributed in the hope that it will be
# useful, but it is provided “as is” and without any express
# or implied warranties. For details, see the full text of
# of the licenses in the directory LICENSES.
# Tests of scannerless parsing -- some corner cases,
# including exhaustion at G1 level
use 5.010001;
use strict;
use Test::More tests => 72;
use English qw( -no_match_vars );
use POSIX qw(setlocale LC_ALL);
POSIX::setlocale(LC_ALL, "C");
use lib 'inc';
my $source_template = <<'END_OF_SOURCE';
:default ::= action => do_list
:start ::= Number
Number ::= number # If I add '+' or '*' it will work...
%QUANTIFIER%
number ~ [\d]+
:discard ~ whitespace
whitespace ~ [\s]+
END_OF_SOURCE
(my $source_bare = $source_template) =~ s/ %QUANTIFIER% / /xms;
(my $source_plus = $source_template) =~ s/ %QUANTIFIER% / + /xms;
(my $source_star = $source_template) =~ s/ %QUANTIFIER% / * /xms;
my $grammar_bare = Marpa::R3::Scanless::G->new(
{
semantics_package => 'My_Actions',
source => \$source_bare
}
);
my $grammar_plus = Marpa::R3::Scanless::G->new(
{
semantics_package => 'My_Actions',
source => \$source_plus
}
);
my $grammar_star = Marpa::R3::Scanless::G->new(
{
semantics_package => 'My_Actions',
source => \$source_star
}
);
package My_Actions;
sub do_list {
return join " ", @{$_[1]};
}
sub show_last_expression {
my ($self) = @_;
my $recce = $self->{slr};
my ( $start, $length ) = $recce->last_completed('Number');
return '[none]' if not defined $start;
my $last_expression = $recce->g1_literal( $start, $length );
return $last_expression;
} ## end sub show_last_expression
package main;
sub my_parser {
my ( $grammar, $string ) = @_;
my $self = bless { grammar => $grammar }, 'My_Actions';
my $recce = Marpa::R3::Scanless::R->new( { grammar => $grammar } );
$self->{slr} = $recce;
my ( $parse_value, $parse_status, $last_expression );
my $eval_ok = eval { $recce->read( \$string ); 1; };
my $eval_error = $EVAL_ERROR;
# Marpa::R3::Display
# name: $recce->exhausted example
my $exhausted_status = $recce->exhausted();
# Marpa::R3::Display::End
if ( not $eval_ok ) {
chomp $eval_error;
$eval_error =~ s/\n.*//xms;
return 'No parse', $eval_error, $self->show_last_expression(),
$exhausted_status;
} ## end if ( not $eval_ok )
my $value_ref = $recce->value($self);
if ( not defined $value_ref ) {
return 'No parse', 'Input read to end but no parse',
$self->show_last_expression(),
$exhausted_status;
}
my $value = ${$value_ref} // '';
return $value, 'Parse OK', 'entire input', $exhausted_status;
} ## end sub my_parser
my %grammar_by_type = (
'Bare' => $grammar_bare,
'Plus' => $grammar_plus,
'Star' => $grammar_star,
);
my @tests_data = (
[ 'Bare', '', 'No parse', 'Input read to end but no parse', '[none]' ],
[ 'Bare', '1', '1', 'Parse OK', 'entire input', 1 ],
[ 'Bare', '1 2', 'No parse',
'Error in SLIF parse: Parse exhausted, but lexemes remain, at line 1, column 3',
'1', 1
],
[ 'Plus', '', 'No parse', 'Input read to end but no parse', '[none]' ],
[ 'Plus', '1', '1', 'Parse OK', 'entire input' ],
[ 'Plus', '1 2', '1 2', 'Parse OK', 'entire input' ],
[ 'Star', '', '', 'Parse OK', 'entire input' ],
[ 'Star', '1', '1', 'Parse OK', 'entire input' ],
[ 'Star', '1 2', '1 2', 'Parse OK', 'entire input' ],
);
for my $trailer ( q{}, q{ } ) {
for my $test_data (@tests_data) {
my ( $type, $test_string, $expected_value, $expected_result,
$expected_last_expression, $expected_exhaustion_status )
= @{$test_data};
$test_string .= $trailer;
my ( $actual_value, $actual_result, $actual_last_expression, $actual_exhaustion_status ) =
my_parser( $grammar_by_type{$type}, $test_string );
Test::More::is( $actual_value, $expected_value,
qq{$type: Value of "$test_string"} );
Test::More::is( $actual_result, $expected_result,
qq{$type: Result of "$test_string"} );
Test::More::is( $actual_last_expression, $expected_last_expression,
qq{$type: Last expression found in "$test_string"} );
if ($actual_exhaustion_status) {
if (not $expected_exhaustion_status) {
Test::More::fail(qq{$type: exhausted for "$test_string", but should not be});
} else {
Test::More::pass(qq{$type: exhausted for "$test_string"});
}
} else {
if ($expected_exhaustion_status) {
Test::More::fail(qq{$type: not exhausted for "$test_string", but should be});
} else {
Test::More::pass(qq{$type: not exhausted for "$test_string"});
}
}
} ## end for my $test_data (@tests_data)
} ## end for my $trailer ( q{}, q{ } )
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