File Coverage

blib/lib/Type/Coercion.pm

Criterion	Covered	Total	%
statement	228	259	87.6
branch	82	124	66.1
condition	51	102	50.0
subroutine	56	61	91.8
pod	35	35	100.0
total	452	581	77.6

package Type::Coercion;

use 5.008001;
use strict;
use warnings;

BEGIN {
	$Type::Coercion::AUTHORITY = 'cpan:TOBYINK';
	$Type::Coercion::VERSION   = '2.010001';
}

$Type::Coercion::VERSION =~ tr/_//d;

use Eval::TypeTiny qw<>;
use Scalar::Util qw< blessed >;
use Types::TypeTiny qw<>;

sub _croak ($;@) { require Error::TypeTiny; goto \&Error::TypeTiny::croak }

require Type::Tiny;

__PACKAGE__->Type::Tiny::_install_overloads(
	q("") => sub {
		caller =~ m{^(Moo::HandleMoose|Sub::Quote)}
			? $_[0]->_stringify_no_magic
			: $_[0]->display_name;
	},
	q(bool) => sub { 1 },
	q(&{})  => "_overload_coderef",
);

__PACKAGE__->Type::Tiny::_install_overloads(
	q(~~) => sub { $_[0]->has_coercion_for_value( $_[1] ) },
) if Type::Tiny::SUPPORT_SMARTMATCH();

sub _overload_coderef {
	my $self = shift;

	if ( "Sub::Quote"->can( "quote_sub" ) && $self->can_be_inlined ) {
		$self->{_overload_coderef} =
			Sub::Quote::quote_sub( $self->inline_coercion( '$_[0]' ) )
			if !$self->{_overload_coderef} || !$self->{_sub_quoted}++;
	}
	else {
		Scalar::Util::weaken( my $weak = $self );
		$self->{_overload_coderef} ||= sub { $weak->coerce( @_ ) };
	}

	$self->{_overload_coderef};
} #/ sub _overload_coderef

sub new {
	my $class  = shift;
	my %params = ( @_ == 1 ) ? %{ $_[0] } : @_;

	$params{name} = '__ANON__' unless exists( $params{name} );
	my $C = delete( $params{type_coercion_map} ) || [];
	my $F = delete( $params{frozen} );

	my $self = bless \%params, $class;
	$self->add_type_coercions( @$C ) if @$C;
	$self->_preserve_type_constraint;
	Scalar::Util::weaken( $self->{type_constraint} );    # break ref cycle
	$self->{frozen} = $F if $F;

	unless ( $self->is_anon ) {

		# First try a fast ASCII-only expression, but fall back to Unicode
		$self->name =~ /^_{0,2}[A-Z][A-Za-z0-9_]+$/sm
			or eval q( use 5.008; $self->name =~ /^_{0,2}\p{Lu}[\p{L}0-9_]+$/sm )
			or _croak '"%s" is not a valid coercion name', $self->name;
	}

	return $self;
} #/ sub new

sub _stringify_no_magic {
	sprintf(
		'%s=%s(0x%08x)', blessed( $_[0] ), Scalar::Util::reftype( $_[0] ),
		Scalar::Util::refaddr( $_[0] )
	);
}

sub name         { $_[0]{name} }
sub display_name { $_[0]{display_name} ||= $_[0]->_build_display_name }
sub library      { $_[0]{library} }

sub type_constraint {
	$_[0]{type_constraint} ||= $_[0]->_maybe_restore_type_constraint;
}
sub type_coercion_map { $_[0]{type_coercion_map} ||= [] }
sub moose_coercion { $_[0]{moose_coercion} ||= $_[0]->_build_moose_coercion }

sub compiled_coercion {
	$_[0]{compiled_coercion} ||= $_[0]->_build_compiled_coercion;
}
sub frozen             { $_[0]{frozen} ||= 0 }
sub coercion_generator { $_[0]{coercion_generator} }
sub parameters         { $_[0]{parameters} }
sub parameterized_from { $_[0]{parameterized_from} }

sub has_library            { exists $_[0]{library} }
sub has_type_constraint    { defined $_[0]->type_constraint }     # sic
sub has_coercion_generator { exists $_[0]{coercion_generator} }
sub has_parameters         { exists $_[0]{parameters} }

# It is possible for the target type constraint to have been garbage collected
# but the type coercion object to still exist, as we only keep a weak
# reference to the target type constraint to prevent cyclical references.
# For this reason, we also keep a copy of the type's compiled check which
# will just be a simple coderef that unlikely has any references to anything.
# We preserve it during the constructor, then in the getter for the type
# constraint, we can quickly rebuild a dummy type constraint using the same
# compiled check we preserved, which will usually be sufficient for our needs.

sub _preserve_type_constraint {
	my $self = shift;
	$self->{_compiled_type_constraint_check} =
		$self->{type_constraint}->compiled_check
		if $self->{type_constraint};
}

sub _maybe_restore_type_constraint {
	my $self = shift;
	if ( my $check = $self->{_compiled_type_constraint_check} ) {
		return Type::Tiny->new( constraint => $check );
	}
	return;    # uncoverable statement
}

sub add {
	my $class = shift;
	my ( $x, $y, $swap ) = @_;

	Types::TypeTiny::is_TypeTiny( $x ) and return $x->plus_fallback_coercions( $y );
	Types::TypeTiny::is_TypeTiny( $y ) and return $y->plus_coercions( $x );

	_croak "Attempt to add $class to something that is not a $class"
		unless blessed( $x )
		&& blessed( $y )
		&& $x->isa( $class )
		&& $y->isa( $class );

	( $y, $x ) = ( $x, $y ) if $swap;

	my %opts;
	if ( $x->has_type_constraint
		and $y->has_type_constraint
		and $x->type_constraint == $y->type_constraint )
	{
		$opts{type_constraint} = $x->type_constraint;
	}
	elsif ( $x->has_type_constraint and $y->has_type_constraint ) {

		#		require Type::Tiny::Union;
		#		$opts{type_constraint} = "Type::Tiny::Union"->new(
		#			type_constraints => [ $x->type_constraint, $y->type_constraint ],
		#		);
	}
	$opts{display_name} ||= "$x+$y";
	delete $opts{display_name} if $opts{display_name} eq '__ANON__+__ANON__';

	my $new = $class->new( %opts );
	$new->add_type_coercions( @{ $x->type_coercion_map } );
	$new->add_type_coercions( @{ $y->type_coercion_map } );
	return $new;
} #/ sub add

sub _build_display_name {
	shift->name;
}

sub qualified_name {
	my $self = shift;

	if ( $self->has_library and not $self->is_anon ) {
		return sprintf( "%s::%s", $self->library, $self->name );
	}

	return $self->name;
}

sub is_anon {
	my $self = shift;
	$self->name eq "__ANON__";
}

sub _clear_compiled_coercion {
	delete $_[0]{_overload_coderef};
	delete $_[0]{compiled_coercion};
}

sub freeze                    { $_[0]{frozen} = 1; $_[0] }
sub i_really_want_to_unfreeze { $_[0]{frozen} = 0; $_[0] }

sub coerce {
	my $self = shift;
	return $self->compiled_coercion->( @_ );
}

sub check_coerce {
	my $self = shift;
	my $r = $self->coerce( @_ );

	if ( $self->has_type_constraint ) {
		my $tc = $self->type_constraint;
		return $tc->check( $r ) ? $r : undef;
	}
	else {
		return $r;
	}
}

sub assert_coerce {
	my $self = shift;
	my $r    = $self->coerce( @_ );
	$self->type_constraint->assert_valid( $r )
		if $self->has_type_constraint;
	return $r;
}

sub has_coercion_for_type {
	my $self = shift;
	my $type = Types::TypeTiny::to_TypeTiny( $_[0] );

	return "0 but true"
		if $self->has_type_constraint
		&& $type->is_a_type_of( $self->type_constraint );

	my $c = $self->type_coercion_map;
	for ( my $i = 0 ; $i <= $#$c ; $i += 2 ) {
		return !!1 if $type->is_a_type_of( $c->[$i] );
	}
	return;
} #/ sub has_coercion_for_type

sub has_coercion_for_value {
	my $self = shift;
	local $_ = $_[0];

	return "0 but true"
		if $self->has_type_constraint
		&& $self->type_constraint->check( @_ );

	my $c = $self->type_coercion_map;
	for ( my $i = 0 ; $i <= $#$c ; $i += 2 ) {
		return !!1 if $c->[$i]->check( @_ );
	}
	return;
} #/ sub has_coercion_for_value

sub add_type_coercions {
	my $self = shift;
	my @args = @_;

	_croak "Attempt to add coercion code to a Type::Coercion which has been frozen"
		if $self->frozen;

	while ( @args ) {
		my $type = Types::TypeTiny::to_TypeTiny( shift @args );

		if ( blessed $type and my $method = $type->can( 'type_coercion_map' ) ) {
			push @{ $self->type_coercion_map }, @{ $method->( $type ) };
		}
		else {
			my $coercion = shift @args;
			_croak "Types must be blessed Type::Tiny objects"
				unless Types::TypeTiny::is_TypeTiny( $type );
			_croak "Coercions must be code references or strings"
				unless Types::TypeTiny::is_StringLike( $coercion )
				|| Types::TypeTiny::is_CodeLike( $coercion );
			push @{ $self->type_coercion_map }, $type, $coercion;
		}
	} #/ while ( @args )

	$self->_clear_compiled_coercion;
	return $self;
} #/ sub add_type_coercions

sub _build_compiled_coercion {
	my $self = shift;

	my @mishmash = @{ $self->type_coercion_map };
	return sub { $_[0] }
		unless @mishmash;

	if ( $self->can_be_inlined ) {
		return Eval::TypeTiny::eval_closure(
			source      => sprintf( 'sub ($) { %s }', $self->inline_coercion( '$_[0]' ) ),
			description => sprintf( "compiled coercion '%s'", $self ),
		);
	}

	# These arrays will be closed over.
	my ( @types, @codes );
	while ( @mishmash ) {
		push @types, shift @mishmash;
		push @codes, shift @mishmash;
	}
	if ( $self->has_type_constraint ) {
		unshift @types, $self->type_constraint;
		unshift @codes, undef;
	}

	my @sub;

	for my $i ( 0 .. $#types ) {
		push @sub,
			$types[$i]->can_be_inlined
			? sprintf( 'if (%s)',                $types[$i]->inline_check( '$_[0]' ) )
			: sprintf( 'if ($checks[%d]->(@_))', $i );
		push @sub,
			!defined( $codes[$i] )
			? sprintf( '  { return $_[0] }' )
			: Types::TypeTiny::is_StringLike( $codes[$i] ) ? sprintf(
			'  { local $_ = $_[0]; return scalar(%s); }',
			$codes[$i]
			)
			: sprintf( '  { local $_ = $_[0]; return scalar($codes[%d]->(@_)) }', $i );
	} #/ for my $i ( 0 .. $#types)

	push @sub, 'return $_[0];';

	return Eval::TypeTiny::eval_closure(
		source      => sprintf( 'sub ($) { %s }', join qq[\n], @sub ),
		description => sprintf( "compiled coercion '%s'", $self ),
		environment => {
			'@checks' => [ map $_->compiled_check, @types ],
			'@codes'  => \@codes,
		},
	);
} #/ sub _build_compiled_coercion

sub can_be_inlined {
	my $self = shift;

	return unless $self->frozen;

	return
		if $self->has_type_constraint
		&& !$self->type_constraint->can_be_inlined;

	my @mishmash = @{ $self->type_coercion_map };
	while ( @mishmash ) {
		my ( $type, $converter ) = splice( @mishmash, 0, 2 );
		return unless $type->can_be_inlined;
		return unless Types::TypeTiny::is_StringLike( $converter );
	}
	return !!1;
} #/ sub can_be_inlined

sub _source_type_union {
	my $self = shift;

	my @r;
	push @r, $self->type_constraint if $self->has_type_constraint;

	my @mishmash = @{ $self->type_coercion_map };
	while ( @mishmash ) {
		my ( $type ) = splice( @mishmash, 0, 2 );
		push @r, $type;
	}

	require Type::Tiny::Union;
	return "Type::Tiny::Union"->new( type_constraints => \@r, tmp => 1 );
} #/ sub _source_type_union

sub inline_coercion {
	my $self    = shift;
	my $varname = $_[0];

	_croak "This coercion cannot be inlined" unless $self->can_be_inlined;

	my @mishmash = @{ $self->type_coercion_map };
	return "($varname)" unless @mishmash;

	my ( @types, @codes );
	while ( @mishmash ) {
		push @types, shift @mishmash;
		push @codes, shift @mishmash;
	}
	if ( $self->has_type_constraint ) {
		unshift @types, $self->type_constraint;
		unshift @codes, undef;
	}

	my @sub;

	for my $i ( 0 .. $#types ) {
		push @sub, sprintf( '(%s) ?', $types[$i]->inline_check( $varname ) );
		push @sub,
			( defined( $codes[$i] ) && ( $varname eq '$_' ) )
			? sprintf( 'scalar(do { %s }) :', $codes[$i] )
			: defined( $codes[$i] ) ? sprintf(
			'scalar(do { local $_ = %s; %s }) :', $varname,
			$codes[$i]
			)
			: sprintf( '%s :', $varname );
	} #/ for my $i ( 0 .. $#types)

	push @sub, "$varname";

	return join q[ ], @sub;
} #/ sub inline_coercion

sub _build_moose_coercion {
	my $self = shift;

	my %options = ();
	$options{type_coercion_map} =
		[ $self->freeze->_codelike_type_coercion_map( 'moose_type' ) ];
	$options{type_constraint} = $self->type_constraint
		if $self->has_type_constraint;

	require Moose::Meta::TypeCoercion;
	my $r = "Moose::Meta::TypeCoercion"->new( %options );

	return $r;
} #/ sub _build_moose_coercion

sub _codelike_type_coercion_map {
	my $self     = shift;
	my $modifier = $_[0];

	my @orig = @{ $self->type_coercion_map };
	my @new;

	while ( @orig ) {
		my ( $type, $converter ) = splice( @orig, 0, 2 );

		push @new, $modifier ? $type->$modifier : $type;

		if ( Types::TypeTiny::is_CodeLike( $converter ) ) {
			push @new, $converter;
		}
		else {
			push @new, Eval::TypeTiny::eval_closure(
				source      => sprintf( 'sub { local $_ = $_[0]; %s }',           $converter ),
				description => sprintf( "temporary compiled converter from '%s'", $type ),
			);
		}
	} #/ while ( @orig )

	return @new;
} #/ sub _codelike_type_coercion_map

sub is_parameterizable {
	shift->has_coercion_generator;
}

sub is_parameterized {
	shift->has_parameters;
}

sub parameterize {
	my $self = shift;
	return $self unless @_;
	$self->is_parameterizable
		or _croak "Constraint '%s' does not accept parameters", "$self";

	@_ = map Types::TypeTiny::to_TypeTiny( $_ ), @_;

	return ref( $self )->new(
		type_constraint   => $self->type_constraint,
		type_coercion_map =>
			[ $self->coercion_generator->( $self, $self->type_constraint, @_ ) ],
		parameters         => \@_,
		frozen             => 1,
		parameterized_from => $self,
	);
} #/ sub parameterize

sub _reparameterize {
	my $self = shift;
	my ( $target_type ) = @_;

	$self->is_parameterized or return $self;
	my $parent = $self->parameterized_from;

	return ref( $self )->new(
		type_constraint   => $target_type,
		type_coercion_map => [
			$parent->coercion_generator->( $parent, $target_type, @{ $self->parameters } )
		],
		parameters         => \@_,
		frozen             => 1,
		parameterized_from => $parent,
	);
} #/ sub _reparameterize

sub isa {
	my $self = shift;

	if ( $INC{"Moose/Meta/TypeCoercion.pm"}
		and blessed( $self )
		and $_[0] eq 'Moose::Meta::TypeCoercion' )
	{
		return !!1;
	}

	if ( $INC{"Moose/Meta/TypeCoercion.pm"}
		and blessed( $self )
		and $_[0] =~ /^(Class::MOP|MooseX?)::/ )
	{
		my $r = $self->moose_coercion->isa( @_ );
		return $r if $r;
	}

	$self->SUPER::isa( @_ );
} #/ sub isa

sub can {
	my $self = shift;

	my $can = $self->SUPER::can( @_ );
	return $can if $can;

	if ( $INC{"Moose/Meta/TypeCoercion.pm"}
		and blessed( $self )
		and my $method = $self->moose_coercion->can( @_ ) )
	{
		return sub { $method->( shift->moose_coercion, @_ ) };
	}

	return;
} #/ sub can

sub AUTOLOAD {
	my $self = shift;
	my ( $m ) = ( our $AUTOLOAD =~ /::(\w+)$/ );
	return if $m eq 'DESTROY';

	if ( $INC{"Moose/Meta/TypeCoercion.pm"}
		and blessed( $self )
		and my $method = $self->moose_coercion->can( $m ) )
	{
		return $method->( $self->moose_coercion, @_ );
	}

	_croak q[Can't locate object method "%s" via package "%s"], $m,
		ref( $self ) || $self;
} #/ sub AUTOLOAD

# Private Moose method, but Moo uses this...
sub _compiled_type_coercion {
	my $self = shift;
	if ( @_ ) {
		my $thing = $_[0];
		if ( blessed( $thing ) and $thing->isa( "Type::Coercion" ) ) {
			$self->add_type_coercions( @{ $thing->type_coercion_map } );
		}
		elsif ( Types::TypeTiny::is_CodeLike( $thing ) ) {
			require Types::Standard;
			$self->add_type_coercions( Types::Standard::Any(), $thing );
		}
	} #/ if ( @_ )
	$self->compiled_coercion;
} #/ sub _compiled_type_coercion

*compile_type_coercion = \&compiled_coercion;
sub meta { _croak( "Not really a Moose::Meta::TypeCoercion. Sorry!" ) }

1;

__END__