File Coverage

blib/lib/Text/MicroTemplate.pm

Criterion	Covered	Total	%
statement	193	226	85.4
branch	81	98	82.6
condition	18	28	64.2
subroutine	28	32	87.5
pod	9	14	64.2
total	329	398	82.6

# modified for NanoA by kazuho, some modified by tokuhirom
# based on Mojo::Template. Copyright (C) 2008, Sebastian Riedel.

package Text::MicroTemplate;

require Exporter;

use strict;
use warnings;
use constant DEBUG => $ENV{MICRO_TEMPLATE_DEBUG} || 0;
use 5.00800;

use Scalar::Util;

our $VERSION = '0.24';
our @ISA = qw(Exporter);
our @EXPORT_OK = qw(encoded_string build_mt render_mt);
our %EXPORT_TAGS = (
    all => [ @EXPORT_OK ],
);
our $_mt_setter = '';

sub new {
    my $class = shift;
    my $self = bless {
        code                => undef,
        comment_mark        => '#',
        expression_mark     => '=',
        line_start          => '?',
        template            => undef,
        tree                => [],
        tag_start           => '
        tag_end             => '?>',
        escape_func         => \&_inline_escape_html,
        prepend             => '',
        package_name        => undef, # defaults to caller
        @_ == 1 ? ref($_[0]) ? %{$_[0]} : (template => $_[0]) : @_,
    }, $class;
    if (defined $self->{template}) {
        $self->parse($self->{template});
    }
    unless (defined $self->{package_name}) {
        $self->{package_name} = 'main';
        my $i = 0;
        while (my $c = caller(++$i)) {
            if ($c !~ /^Text::MicroTemplate\b/) {
                $self->{package_name} = $c;
                last;
            }
        }
    }
    $self;
}

sub escape_func {
    my $self = shift;
    if (@_) {
        $self->{escape_func} = shift;
    }
    $self->{escape_func};
}

sub package_name {
    my $self = shift;
    if (@_) {
        $self->{package_name} = shift;
    }
    $self->{package_name};
}

sub template { shift->{template} }

sub code {
    my $self = shift;
    unless (defined $self->{code}) {
        $self->_build();
    }
    $self->{code};
}

sub _build {
    my $self = shift;

    my $escape_func = $self->{escape_func} || '';

    my $embed_escape_func = ref($escape_func) eq 'CODE'
        ? $escape_func
        : sub{ $escape_func . "(@_)" };

    # Compile
    my @lines;
    my $last_was_code;
    my $last_text;
    for my $line (@{$self->{tree}}) {

        # New line
        push @lines, '';
        for (my $j = 0; $j < @{$line}; $j += 2) {
            my $type  = $line->[$j];
            my $value = $line->[$j + 1];

            if ($type ne 'text' && defined $last_text) {
                # do not mess the start of current line, since it might be
                # the start of "=pod", etc.
                $lines[
                    $j == 0 && @lines >= 2 ? -2 : -1
                ] .= "\$_MT .=\"$last_text\";";
                undef $last_text;
            }

            # Need to fix line ending?
            my $newline = chomp $value;

            # add semicolon to last line of code
            if ($last_was_code && $type ne 'code') {
                $lines[-1] .= ';';
                undef $last_was_code;
            }

            # Text
            if ($type eq 'text') {

                # Quote and fix line ending
                $value = quotemeta($value);
                $value .= '\n' if $newline;

                $last_text = defined $last_text ? "$last_text$value" : $value;
            }

            # Code
            if ($type eq 'code') {
                $lines[-1] .= $value;
                $last_was_code = 1;
            }

            # Expression
            if ($type eq 'expr') {
                my $escaped = $embed_escape_func->('$_MT_T');
                if ($newline && $value =~ /\n/) {
                    $value .= "\n"; # temporary workaround for t/13-heredoc.t
                }
                $lines[-1] .= "\$_MT_T = $value;\$_MT .= ref \$_MT_T eq 'Text::MicroTemplate::EncodedString' ? \$\$_MT_T : $escaped; \$_MT_T = '';";
            }
        }
    }

    # add semicolon to last line of code
    if ($last_was_code) {
        $lines[-1] .= "\n;";
    }
    # add last text line(s)
    if (defined $last_text) {
        $lines[-1] .= "\$_MT .=\"$last_text\";";
    }

    # Wrap
    $lines[0]   = q/sub { my $_MT = ''; local $/ . $self->{package_name} . q/::_MTREF = \$_MT; my $_MT_T = '';/ . (@lines ? $lines[0] : '');
    $lines[-1] .= q/return $_MT; }/;

    $self->{code} = join "\n", @lines;
    return $self;
}

# I am so smart! I am so smart! S-M-R-T! I mean S-M-A-R-T...
sub parse {
    my ($self, $tmpl) = @_;
    $self->{template} = $tmpl;

    # Clean start
    delete $self->{tree};
    delete $self->{code};

    # Tags
    my $line_start    = quotemeta $self->{line_start};
    my $tag_start     = quotemeta $self->{tag_start};
    my $tag_end       = quotemeta $self->{tag_end};
    my $cmnt_mark     = quotemeta $self->{comment_mark};
    my $expr_mark     = quotemeta $self->{expression_mark};

    # Tokenize
    my $state = 'text';
    my @lines = split /(\n)/, $tmpl;
    my $tokens = [];
    while (@lines) {
        my $line = shift @lines;
        my $newline = undef;
        if (@lines) {
            shift @lines;
            $newline = 1;
        }

        if ($state eq 'text') {
            # Perl line without return value
            if ($line =~ /^$line_start\s+(.*)$/) {
                push @{$self->{tree}}, ['code', $1];
                next;
            }
            # Perl line with return value
            if ($line =~ /^$line_start$expr_mark\s+(.+)$/) {
                push @{$self->{tree}}, [
                    'expr', $1,
                    $newline ? ('text', "\n") : (),
                ];
                next;
            }
            # Comment line, dummy token needed for line count
            if ($line =~ /^$line_start$cmnt_mark/) {
                push @{$self->{tree}}, [];
                next;
            }
        }

        # Escaped line ending?
        if ($line =~ /(\\+)$/) {
            my $length = length $1;
            # Newline escaped
            if ($length == 1) {
                $line =~ s/\\$//;
            }
            # Backslash escaped
            if ($length >= 2) {
                $line =~ s/\\\\$/\\/;
                $line .= "\n";
            }
        } else {
            $line .= "\n" if $newline;
        }

        # Mixed line
        for my $token (split /
            (
                $tag_start$expr_mark     # Expression
            |
                $tag_start$cmnt_mark     # Comment
            |
                $tag_start               # Code
            |
                $tag_end                 # End
            )
        /x, $line) {

            # handle tags and bail out
            if ($token eq '') {
                next;
            } elsif ($token =~ /^$tag_end$/) {
                $state = 'text';
                next;
            } elsif ($token =~ /^$tag_start$/) {
                $state = 'code';
                next;
            } elsif ($token =~ /^$tag_start$cmnt_mark$/) {
                $state = 'cmnt';
                next;
            } elsif ($token =~ /^$tag_start$expr_mark$/) {
                $state = 'expr';
                next;
            }

            # value
            if ($state eq 'text') {
                push @$tokens, $state, $token;
            } elsif ($state eq 'cmnt') {
                next; # ignore comments
            } elsif ($state eq 'cont') {
                $tokens->[-1] .= $token;
            } else {
                # state is code or expr
                push @$tokens, $state, $token;
                $state = 'cont';
            }
        }
        if ($state eq 'text') {
            push @{$self->{tree}}, $tokens;
            $tokens = [];
        }
    }
    push @{$self->{tree}}, $tokens
        if @$tokens;

    return $self;
}

sub _context {
    my ($self, $text, $line) = @_;
    my @lines  = split /\n/, $text;

    join '', map {
        0 < $_ && $_ <= @lines ? sprintf("%4d: %s\n", $_, $lines[$_ - 1]) : ''
    } ($line - 2) .. ($line + 2);
}

# Debug goodness
sub _error {
    my ($self, $error, $line_offset, $from) = @_;

    # Line
    if ($error =~ /^(.*)\s+at\s+\(eval\s+\d+\)\s+line\s+(\d+)/) {
        my $reason = $1;
        my $line   = $2 - $line_offset;
        my $delim  = '-' x 76;

        my $report = "$reason at line $line in template passed from $from.\n";
        my $template = $self->_context($self->{template}, $line);
        $report .= "$delim\n$template$delim\n";

        # Advanced debugging
        if (DEBUG) {
            my $code = $self->_context($self->code, $line);
            $report .= "$code$delim\n";
            $report .= $error;
        }

        return $report;
    }

    # No line found
    return "Template error: $error";
}

# create raw string (that does not need to be escaped)
sub encoded_string {
    Text::MicroTemplate::EncodedString->new($_[0]);
}


sub _inline_escape_html{
    my($variable) = @_;

    my $source = qq{
        do{
            $variable =~ s/([&><"'])/\$Text::MicroTemplate::_escape_table{\$1}/ge;
            $variable;
        }
    }; #" for poor editors
    $source =~ s/\n//g; # to keep line numbers
    return $source;
}

our %_escape_table = ( '&' => '&', '>' => '>', '<' => '<', q{"} => '"', q{'} => ''' );
sub escape_html {
    my $str = shift;
    return ''
        unless defined $str;
    return $str->as_string
        if ref $str eq 'Text::MicroTemplate::EncodedString';
    $str =~ s/([&><"'])/$_escape_table{$1}/ge; #' for poor editors
    return $str;
}

sub build_mt {
    my $mt = Text::MicroTemplate->new(@_);
    $mt->build();
}

sub build {
    my $_mt = shift;
    Scalar::Util::weaken($_mt) if $_mt_setter;
    my $_code = $_mt->code;
    my $_from = sub {
        my $i = 0;
        while (my @c = caller(++$i)) {
            return "$c[1] at line $c[2]"
                if $c[0] ne __PACKAGE__;
        }
        '';
    }->();
    my $line_offset = (() = ($_mt->{prepend} =~ /\n/sg)) + 5;
    my $expr = << "...";
package $_mt->{package_name};
sub {
    ${_mt_setter}local \$SIG{__WARN__} = sub { print STDERR \$_mt->_error(shift, $line_offset, \$_from) };
    $_mt->{prepend}
    Text::MicroTemplate::encoded_string((
        $_code
    )->(\@_));
}
...

    if(DEBUG >= 2){
        DEBUG >= 3 ? die $expr : warn $expr;
    }

    my $die_msg;
    {
        local $@;
        if (my $_builder = eval($expr)) {
            return $_builder;
        }
        $die_msg = $_mt->_error($@, $line_offset, $_from);
    }
    die $die_msg;
}

sub render_mt {
    my $builder = build_mt(shift);
    $builder->(@_);
}

# ? $_mt->filter(sub { s/\s+//smg; s/[\r\n]//g; })->(sub { ... ? });
sub filter {
    my ($self, $callback) = @_;
    my $mtref = do {
        no strict 'refs';
        ${"$self->{package_name}::_MTREF"};
    };
    my $before = $$mtref;
    $$mtref = '';
    return sub {
        my $inner_func = shift;
        $inner_func->(@_);

        ## sub { s/foo/bar/g } is a valid filter
        ## sub { DateTime::Format::Foo->parse_string(shift) } is valid too
        local $_ = $$mtref;
        my $retval = $callback->($$mtref);
        no warnings 'uninitialized';
        if (($retval =~ /^\d+$/ and $_ ne $$mtref) or (defined $retval and !$retval)) {
            $$mtref = $before . $_;
        } else {
            $$mtref = $before . $retval;
        }
    }
}

package Text::MicroTemplate::EncodedString;

use strict;
use warnings;

use overload q{""} => sub { shift->as_string }, fallback => 1;

sub new {
    my ($klass, $str) = @_;
    bless \$str, $klass;
}

sub as_string {
    my $self = shift;
    $$self;
}

1;
__END__