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use 5.010;
use strict;
use Scalar::Util qw( looks_like_number );
use vars qw( $VERSION @ISA @EXPORT );
=head1 NAME
Carp::Assert::More - Convenience assertions for common situations
=head1 VERSION
Version 2.9.0
=cut
our $VERSION = '2.9.0';
our @EXPORT = qw(
assert
assert_all_keys_in
assert_and
assert_aoh
assert_arrayref
assert_arrayref_nonempty
assert_arrayref_nonempty_of
assert_arrayref_of
assert_arrayref_all
assert_cmp
assert_coderef
assert_context_list
assert_context_nonvoid
assert_context_scalar
assert_context_void
assert_datetime
assert_defined
assert_empty
assert_exists
assert_fail
assert_hashref
assert_hashref_nonempty
assert_in
assert_integer
assert_integer_between
assert_is
assert_isa
assert_isa_in
assert_isnt
assert_keys_are
assert_lacks
assert_like
assert_listref
assert_negative
assert_negative_integer
assert_nonblank
assert_nonempty
assert_nonnegative
assert_nonnegative_integer
assert_nonref
assert_nonzero
assert_nonzero_integer
assert_numeric
assert_numeric_between
assert_or
assert_positive
assert_positive_integer
assert_regex
assert_undefined
assert_unlike
assert_xor
);
my $INTEGER = qr/^-?\d+$/;
=head1 SYNOPSIS
A set of convenience functions for common assertions.
use Carp::Assert::More;
my $obj = My::Object;
assert_isa( $obj, 'My::Object', 'Got back a correct object' );
=head1 DESCRIPTION
Carp::Assert::More is a convenient set of assertions to make the habit
of writing assertions even easier.
Everything in here is effectively syntactic sugar. There's no technical
difference between calling one of these functions:
assert_datetime( $foo );
assert_isa( $foo, 'DateTime' );
that are provided by Carp::Assert::More and calling these assertions
from Carp::Assert
assert( defined $foo );
assert( ref($foo) eq 'DateTime' );
My intent here is to make common assertions easy so that we as programmers
have no excuse to not use them.
=head1 SIMPLE ASSERTIONS
=head2 assert( $condition [, $name] )
Asserts that C<$condition> is a true value. This is the same as C<assert>
in C<Carp::Assert>, provided as a convenience.
=cut
sub assert($;$) {
my $condition = shift;
my $name = shift;
return if $condition;
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_is( $string, $match [,$name] )
Asserts that I<$string> is the same string value as I<$match>.
C<undef> is not converted to an empty string. If both strings are
C<undef>, they match. If only one string is C<undef>, they don't match.
=cut
sub assert_is($$;$) {
my $string = shift;
my $match = shift;
my $name = shift;
if ( defined($string) ) {
return if defined($match) && ($string eq $match);
}
else {
return if !defined($match);
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_isnt( $string, $unmatch [,$name] )
Asserts that I<$string> does NOT have the same string value as I<$unmatch>.
C<undef> is not converted to an empty string.
=cut
sub assert_isnt($$;$) {
my $string = shift;
my $unmatch = shift;
my $name = shift;
# undef only matches undef
return if defined($string) xor defined($unmatch);
return if defined($string) && defined($unmatch) && ($string ne $unmatch);
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_cmp( $x, $op, $y [,$name] )
Asserts that the relation C<$x $op $y> is true. It lets you know why
the comparsison failed, rather than simply that it did fail, by giving
better diagnostics than a plain C<assert()>, as well as showing the
operands in the stacktrace.
Plain C<assert()>:
assert( $nitems <= 10, 'Ten items or fewer in the express lane' );
Assertion (Ten items or fewer in the express lane) failed!
Carp::Assert::assert("", "Ten items or fewer in the express lane") called at foo.pl line 12
With C<assert_cmp()>:
assert_cmp( $nitems, '<=', 10, 'Ten items or fewer in the express lane' );
Assertion (Ten items or fewer in the express lane) failed!
Failed: 14 <= 10
Carp::Assert::More::assert_cmp(14, "<=", 10, "Ten items or fewer in the express lane") called at foo.pl line 11
The following operators are supported:
=over 4
=item * == numeric equal
=item * != numeric not equal
=item * > numeric greater than
=item * >= numeric greater than or equal
=item * < numeric less than
=item * <= numeric less than or equal
=item * lt string less than
=item * le string less than or equal
=item * gt string less than
=item * ge string less than or equal
=back
There is no support for C<eq> or C<ne> because those already have
C<assert_is> and C<assert_isnt>, respectively.
If either C<$x> or C<$y> is undef, the assertion will fail.
If the operator is numeric, and C<$x> or C<$y> are not numbers, the assertion will fail.
=cut
sub assert_cmp($$$;$) {
my $x = shift;
my $op = shift;
my $y = shift;
my $name = shift;
my $why;
if ( !defined($op) ) {
$why = 'Invalid operator <undef>';
}
elsif ( $op eq '==' ) {
return if looks_like_number($x) && looks_like_number($y) && ($x == $y);
}
elsif ( $op eq '!=' ) {
return if looks_like_number($x) && looks_like_number($y) && ($x != $y);
}
elsif ( $op eq '<' ) {
return if looks_like_number($x) && looks_like_number($y) && ($x < $y);
}
elsif ( $op eq '<=' ) {
return if looks_like_number($x) && looks_like_number($y) && ($x <= $y);
}
elsif ( $op eq '>' ) {
return if looks_like_number($x) && looks_like_number($y) && ($x > $y);
}
elsif ( $op eq '>=' ) {
return if looks_like_number($x) && looks_like_number($y) && ($x >= $y);
}
elsif ( $op eq 'lt' ) {
return if defined($x) && defined($y) && ($x lt $y);
}
elsif ( $op eq 'le' ) {
return if defined($x) && defined($y) && ($x le $y);
}
elsif ( $op eq 'gt' ) {
return if defined($x) && defined($y) && ($x gt $y);
}
elsif ( $op eq 'ge' ) {
return if defined($x) && defined($y) && ($x ge $y);
}
else {
$why = qq{Invalid operator "$op"};
}
$why //= "Failed: " . ($x // 'undef') . ' ' . $op . ' ' . ($y // 'undef');
require Carp;
&Carp::confess( _failure_msg($name, $why) );
}
=head2 assert_like( $string, qr/regex/ [,$name] )
Asserts that I<$string> matches I<qr/regex/>.
The assertion fails either the string or the regex are undef.
=cut
sub assert_like($$;$) {
my $string = shift;
my $regex = shift;
my $name = shift;
if ( defined($string) && !ref($string) ) {
if ( ref($regex) ) {
return if $string =~ $regex;
}
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_unlike( $string, qr/regex/ [,$name] )
Asserts that I<$string> matches I<qr/regex/>.
The assertion fails if the regex is undef.
=cut
sub assert_unlike($$;$) {
my $string = shift;
my $regex = shift;
my $name = shift;
return if !defined($string);
if ( ref($regex) eq 'Regexp' ) {
return if $string !~ $regex;
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_defined( $this [, $name] )
Asserts that I<$this> is defined.
=cut
sub assert_defined($;$) {
return if defined( $_[0] );
require Carp;
&Carp::confess( _failure_msg($_[1]) );
}
=head2 assert_undefined( $this [, $name] )
Asserts that I<$this> is not defined.
=cut
sub assert_undefined($;$) {
return unless defined( $_[0] );
require Carp;
&Carp::confess( _failure_msg($_[1]) );
}
=head2 assert_nonblank( $this [, $name] )
Asserts that I<$this> is not a reference and is not an empty string.
=cut
sub assert_nonblank($;$) {
my $this = shift;
my $name = shift;
my $why;
if ( !defined($this) ) {
$why = 'Value is undef.';
}
else {
if ( ref($this) ) {
$why = 'Value is a reference to ' . ref($this) . '.';
}
else {
return if $this ne '';
$why = 'Value is blank.';
}
}
require Carp;
&Carp::confess( _failure_msg($name, $why) );
}
=head1 BOOLEAN ASSERTIONS
These boolean assertions help make diagnostics more useful.
If you use C<assert> with a boolean condition:
assert( $x && $y, 'Both X and Y should be true' );
you can't tell why it failed:
Assertion (Both X and Y should be true) failed!
at .../Carp/Assert/More.pm line 123
Carp::Assert::More::assert(undef, 'Both X and Y should be true') called at foo.pl line 16
But if you use C<assert_and>:
assert_and( $x, $y, 'Both X and Y should be true' );
the stacktrace tells you which half of the expression failed.
Assertion (Both X and Y should be true) failed!
at .../Carp/Assert/More.pm line 123
Carp::Assert::More::assert_and('thing', undef, 'Both X and Y should be true') called at foo.pl line 16
=head2 assert_and( $x, $y [, $name] )
Asserts that both C<$x> and C<$y> are true.
=cut
sub assert_and($$;$) {
my $x = shift;
my $y = shift;
my $name = shift;
return if $x && $y;
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_or( $x, $y [, $name] )
Asserts that at least one of C<$x> or C<$y> are true.
=cut
sub assert_or($$;$) {
my $x = shift;
my $y = shift;
my $name = shift;
return if $x || $y;
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_xor( $x, $y [, $name] )
Asserts that C<$x> is true, or C<$y> is true, but not both.
=cut
sub assert_xor($$;$) {
my $x = shift;
my $y = shift;
my $name = shift;
return if $x && !$y;
return if $y && !$x;
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head1 NUMERIC ASSERTIONS
=head2 assert_numeric( $n [, $name] )
Asserts that C<$n> looks like a number, according to C<Scalar::Util::looks_like_number>.
C<undef> will always fail.
=cut
sub assert_numeric {
my $n = shift;
my $name = shift;
return if Scalar::Util::looks_like_number( $n );
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_integer( $this [, $name ] )
Asserts that I<$this> is an integer, which may be zero or negative.
assert_integer( 0 ); # pass
assert_integer( 14 ); # pass
assert_integer( -14 ); # pass
assert_integer( '14.' ); # FAIL
=cut
sub assert_integer($;$) {
my $this = shift;
my $name = shift;
if ( defined($this) ) {
return if $this =~ $INTEGER;
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_nonzero( $this [, $name ] )
Asserts that the numeric value of I<$this> is defined and is not zero.
assert_nonzero( 0 ); # FAIL
assert_nonzero( -14 ); # pass
assert_nonzero( '14.' ); # pass
=cut
sub assert_nonzero($;$) {
my $this = shift;
my $name = shift;
if ( Scalar::Util::looks_like_number($this) ) {
return if $this != 0;
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_positive( $this [, $name ] )
Asserts that I<$this> is defined, numeric and greater than zero.
assert_positive( 0 ); # FAIL
assert_positive( -14 ); # FAIL
assert_positive( '14.' ); # pass
=cut
sub assert_positive($;$) {
my $this = shift;
my $name = shift;
if ( Scalar::Util::looks_like_number($this) ) {
return if ($this+0 > 0);
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_nonnegative( $this [, $name ] )
Asserts that I<$this> is defined, numeric and greater than or equal
to zero.
assert_nonnegative( 0 ); # pass
assert_nonnegative( -14 ); # FAIL
assert_nonnegative( '14.' ); # pass
assert_nonnegative( 'dog' ); # pass
=cut
sub assert_nonnegative($;$) {
my $this = shift;
my $name = shift;
if ( Scalar::Util::looks_like_number( $this ) ) {
return if $this >= 0;
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_negative( $this [, $name ] )
Asserts that the numeric value of I<$this> is defined and less than zero.
assert_negative( 0 ); # FAIL
assert_negative( -14 ); # pass
assert_negative( '14.' ); # FAIL
=cut
sub assert_negative($;$) {
my $this = shift;
my $name = shift;
no warnings;
return if defined($this) && ($this+0 < 0);
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_nonzero_integer( $this [, $name ] )
Asserts that the numeric value of I<$this> is defined, an integer, and not zero.
assert_nonzero_integer( 0 ); # FAIL
assert_nonzero_integer( -14 ); # pass
assert_nonzero_integer( '14.' ); # FAIL
=cut
sub assert_nonzero_integer($;$) {
my $this = shift;
my $name = shift;
if ( defined($this) && ($this =~ $INTEGER) ) {
return if $this != 0;
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_positive_integer( $this [, $name ] )
Asserts that the numeric value of I<$this> is defined, an integer and greater than zero.
assert_positive_integer( 0 ); # FAIL
assert_positive_integer( -14 ); # FAIL
assert_positive_integer( '14.' ); # FAIL
assert_positive_integer( '14' ); # pass
=cut
sub assert_positive_integer($;$) {
my $this = shift;
my $name = shift;
if ( defined($this) && ($this =~ $INTEGER) ) {
return if $this > 0;
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_nonnegative_integer( $this [, $name ] )
Asserts that the numeric value of I<$this> is defined, an integer, and not less than zero.
assert_nonnegative_integer( 0 ); # pass
assert_nonnegative_integer( -14 ); # FAIL
assert_nonnegative_integer( '14.' ); # FAIL
=cut
sub assert_nonnegative_integer($;$) {
my $this = shift;
my $name = shift;
if ( defined($this) && ($this =~ $INTEGER) ) {
return if $this >= 0;
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_negative_integer( $this [, $name ] )
Asserts that the numeric value of I<$this> is defined, an integer, and less than zero.
assert_negative_integer( 0 ); # FAIL
assert_negative_integer( -14 ); # pass
assert_negative_integer( '14.' ); # FAIL
=cut
sub assert_negative_integer($;$) {
my $this = shift;
my $name = shift;
if ( defined($this) && ($this =~ $INTEGER) ) {
return if $this < 0;
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_numeric_between( $n, $lo, $hi [, $name ] )
Asserts that the value of I<$this> is defined, numeric and between C<$lo>
and C<$hi>, inclusive.
assert_numeric_between( 15, 10, 100 ); # pass
assert_numeric_between( 10, 15, 100 ); # FAIL
assert_numeric_between( 3.14, 1, 10 ); # pass
=cut
sub assert_numeric_between($$$;$) {
my $n = shift;
my $lo = shift;
my $hi = shift;
my $name = shift;
if ( Scalar::Util::looks_like_number( $n ) ) {
return if $lo <= $n && $n <= $hi;
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_integer_between( $n, $lo, $hi [, $name ] )
Asserts that the value of I<$this> is defined, an integer, and between C<$lo>
and C<$hi>, inclusive.
assert_integer_between( 15, 10, 100 ); # pass
assert_integer_between( 10, 15, 100 ); # FAIL
assert_integer_between( 3.14, 1, 10 ); # FAIL
=cut
sub assert_integer_between($$$;$) {
my $n = shift;
my $lo = shift;
my $hi = shift;
my $name = shift;
if ( defined($n) && $n =~ $INTEGER ) {
return if $lo <= $n && $n <= $hi;
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head1 REFERENCE ASSERTIONS
=head2 assert_isa( $this, $type [, $name ] )
Asserts that I<$this> is an object of type I<$type>.
=cut
sub assert_isa($$;$) {
my $this = shift;
my $type = shift;
my $name = shift;
# The assertion is true if
# 1) For objects, $this is of class $type or of a subclass of $type
# 2) For non-objects, $this is a reference to a HASH, SCALAR, ARRAY, etc.
return if Scalar::Util::blessed( $this ) && $this->isa( $type );
return if ref($this) eq $type;
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_isa_in( $obj, \@types [, $description] )
Assert that the blessed C<$obj> isa one of the types in C<\@types>.
assert_isa_in( $obj, [ 'My::Foo', 'My::Bar' ], 'Must pass either a Foo or Bar object' );
=cut
sub assert_isa_in($$;$) {
my $obj = shift;
my $types = shift;
my $name = shift;
if ( Scalar::Util::blessed($obj) ) {
for ( @{$types} ) {
return if $obj->isa($_);
}
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_empty( $this [, $name ] )
I<$this> must be a ref to either a hash or an array. Asserts that that
collection contains no elements. Will assert (with its own message,
not I<$name>) unless given a hash or array ref. It is OK if I<$this> has
been blessed into objecthood, but the semantics of checking an object to see
if it does not have keys (for a hashref) or returns 0 in scalar context (for
an array ref) may not be what you want.
assert_empty( 0 ); # FAIL
assert_empty( 'foo' ); # FAIL
assert_empty( undef ); # FAIL
assert_empty( {} ); # pass
assert_empty( [] ); # pass
assert_empty( {foo=>1} );# FAIL
assert_empty( [1,2,3] ); # FAIL
=cut
sub assert_empty($;$) {
my $ref = shift;
my $name = shift;
my $underlying_type;
if ( Scalar::Util::blessed( $ref ) ) {
$underlying_type = Scalar::Util::reftype( $ref );
}
else {
$underlying_type = ref( $ref );
}
my $why;
my $n;
if ( $underlying_type eq 'HASH' ) {
return if scalar keys %{$ref} == 0;
$n = scalar keys %{$ref};
$why = "Hash contains $n key";
}
elsif ( $underlying_type eq 'ARRAY' ) {
return if @{$ref} == 0;
$n = scalar @{$ref};
$why = "Array contains $n element";
}
else {
$why = 'Argument is not a hash or array.';
}
$why .= 's' if $n && ($n>1);
$why .= '.';
require Carp;
&Carp::confess( _failure_msg($name, $why) );
}
=head2 assert_nonempty( $this [, $name ] )
I<$this> must be a ref to either a hash or an array. Asserts that that
collection contains at least 1 element. Will assert (with its own message,
not I<$name>) unless given a hash or array ref. It is OK if I<$this> has
been blessed into objecthood, but the semantics of checking an object to see
if it has keys (for a hashref) or returns >0 in scalar context (for an array
ref) may not be what you want.
assert_nonempty( 0 ); # FAIL
assert_nonempty( 'foo' ); # FAIL
assert_nonempty( undef ); # FAIL
assert_nonempty( {} ); # FAIL
assert_nonempty( [] ); # FAIL
assert_nonempty( {foo=>1} );# pass
assert_nonempty( [1,2,3] ); # pass
=cut
sub assert_nonempty($;$) {
my $ref = shift;
my $name = shift;
my $underlying_type;
if ( Scalar::Util::blessed( $ref ) ) {
$underlying_type = Scalar::Util::reftype( $ref );
}
else {
$underlying_type = ref( $ref );
}
my $why;
my $n;
if ( $underlying_type eq 'HASH' ) {
return if scalar keys %{$ref} > 0;
$why = "Hash contains 0 keys.";
}
elsif ( $underlying_type eq 'ARRAY' ) {
return if scalar @{$ref} > 0;
$why = "Array contains 0 elements.";
}
else {
$why = 'Argument is not a hash or array.';
}
require Carp;
&Carp::confess( _failure_msg($name, $why) );
}
=head2 assert_nonref( $this [, $name ] )
Asserts that I<$this> is not undef and not a reference.
=cut
sub assert_nonref($;$) {
my $this = shift;
my $name = shift;
assert_defined( $this, $name );
return unless ref( $this );
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_hashref( $ref [,$name] )
Asserts that I<$ref> is defined, and is a reference to a (possibly empty) hash.
B<NB:> This method returns I<false> for objects, even those whose underlying
data is a hashref. This is as it should be, under the assumptions that:
=over 4
=item (a)
you shouldn't rely on the underlying data structure of a particular class, and
=item (b)
you should use C<assert_isa> instead.
=back
=cut
sub assert_hashref($;$) {
my $ref = shift;
my $name = shift;
if ( ref($ref) eq 'HASH' || (Scalar::Util::blessed( $ref ) && $ref->isa( 'HASH' )) ) {
return;
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_hashref_nonempty( $ref [,$name] )
Asserts that I<$ref> is defined and is a reference to a hash with at
least one key/value pair.
=cut
sub assert_hashref_nonempty($;$) {
my $ref = shift;
my $name = shift;
if ( ref($ref) eq 'HASH' || (Scalar::Util::blessed( $ref ) && $ref->isa( 'HASH' )) ) {
return if scalar keys %{$ref} > 0;
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_arrayref( $ref [, $name] )
=head2 assert_listref( $ref [,$name] )
Asserts that I<$ref> is defined, and is a reference to an array, which
may or may not be empty.
B<NB:> The same caveat about objects whose underlying structure is a
hash (see C<assert_hashref>) applies here; this method returns false
even for objects whose underlying structure is an array.
C<assert_listref> is an alias for C<assert_arrayref> and may go away in
the future. Use C<assert_arrayref> instead.
=cut
sub assert_arrayref($;$) {
my $ref = shift;
my $name = shift;
if ( ref($ref) eq 'ARRAY' || (Scalar::Util::blessed( $ref ) && $ref->isa( 'ARRAY' )) ) {
return;
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
*assert_listref = *assert_arrayref;
=head2 assert_arrayref_nonempty( $ref [, $name] )
Asserts that I<$ref> is reference to an array that has at least one element in it.
=cut
sub assert_arrayref_nonempty($;$) {
my $ref = shift;
my $name = shift;
if ( ref($ref) eq 'ARRAY' || (Scalar::Util::blessed( $ref ) && $ref->isa( 'ARRAY' )) ) {
return if scalar @{$ref} > 0;
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_arrayref_of( $ref, $type [, $name] )
Asserts that I<$ref> is reference to an array, and any/all elements are
of type I<$type>.
For example:
my @users = get_users();
assert_arrayref_of( \@users, 'My::User' );
=cut
sub assert_arrayref_of($$;$) {
my $ref = shift;
my $type = shift;
my $name = shift;
my $ok;
my @why;
if ( ref($ref) eq 'ARRAY' || (Scalar::Util::blessed( $ref ) && $ref->isa( 'ARRAY' )) ) {
my $n = 0;
for my $i ( @{$ref} ) {
if ( !( ( Scalar::Util::blessed( $i ) && $i->isa( $type ) ) || (ref($i) eq $type) ) ) {
push @why, "Element #$n is not of type $type";
}
++$n;
}
$ok = !@why;
}
if ( !$ok ) {
require Carp;
&Carp::confess( _failure_msg($name), @why );
}
return;
}
=head2 assert_arrayref_nonempty_of( $ref, $type [, $name] )
Asserts that I<$ref> is reference to an array, that it has at least one
element, and that all elements are of type I<$type>.
This is the same function as C<assert_arrayref_of>, except that it also
requires at least one element.
=cut
sub assert_arrayref_nonempty_of($$;$) {
my $ref = shift;
my $type = shift;
my $name = shift;
my $ok;
my @why;
if ( ref($ref) eq 'ARRAY' || (Scalar::Util::blessed( $ref ) && $ref->isa( 'ARRAY' )) ) {
if ( scalar @{$ref} > 0 ) {
my $n = 0;
for my $i ( @{$ref} ) {
if ( !( ( Scalar::Util::blessed( $i ) && $i->isa( $type ) ) || (ref($i) eq $type) ) ) {
push @why, "Element #$n is not of type $type";
}
++$n;
}
$ok = !@why;
}
else {
push @why, 'Array contains no elements';
}
}
if ( !$ok ) {
require Carp;
&Carp::confess( _failure_msg($name), @why );
}
return;
}
=head2 assert_arrayref_all( $aref, $sub [, $name] )
Asserts that I<$aref> is reference to an array that has at least one
element in it. Each element of the array is passed to subroutine I<$sub>
which is assumed to be an assertion.
For example:
my $aref_of_counts = get_counts();
assert_arrayref_all( $aref, \&assert_positive_integer, 'Counts are positive' );
Whatever is passed as I<$name>, a string saying "Element #N" will be
appended, where N is the zero-based index of the array.
=cut
sub assert_arrayref_all($$;$) {
my $aref = shift;
my $sub = shift;
my $name = shift;
my @why;
assert_coderef( $sub, 'assert_arrayref_all requires a code reference' );
if ( ref($aref) eq 'ARRAY' || (Scalar::Util::blessed( $aref ) && $aref->isa( 'ARRAY' )) ) {
if ( @{$aref} ) {
my $inner_msg = defined($name) ? "$name: " : 'assert_arrayref_all: ';
my $n = 0;
for my $i ( @{$aref} ) {
$sub->( $i, "${inner_msg}Element #$n" );
++$n;
}
}
else {
push @why, 'Array contains no elements';
}
}
else {
push @why, 'First argument to assert_arrayref_all was not an array';
}
if ( @why ) {
require Carp;
&Carp::confess( _failure_msg($name), @why );
}
return;
}
=head2 assert_aoh( $ref [, $name ] )
Verifies that C<$array> is an arrayref, and that every element is a hashref.
The array C<$array> can be an empty arraref and the assertion will pass.
=cut
sub assert_aoh {
my $ref = shift;
my $name = shift;
my $ok = 0;
if ( ref($ref) eq 'ARRAY' || (Scalar::Util::blessed( $ref ) && $ref->isa( 'ARRAY' )) ) {
$ok = 1;
for my $val ( @{$ref} ) {
if ( not ( ref($val) eq 'HASH' || (Scalar::Util::blessed( $val) && $val->isa( 'HASH' )) ) ) {
$ok = 0;
last;
}
}
}
return if $ok;
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_coderef( $ref [,$name] )
Asserts that I<$ref> is defined, and is a reference to a closure.
=cut
sub assert_coderef($;$) {
my $ref = shift;
my $name = shift;
if ( ref($ref) eq 'CODE' || (Scalar::Util::blessed( $ref ) && $ref->isa( 'CODE' )) ) {
return;
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_regex( $ref [,$name] )
Asserts that I<$ref> is defined, and is a reference to a regex.
It is functionally the same as C<assert_isa( $ref, 'Regexp' )>.
=cut
sub assert_regex($;$) {
my $ref = shift;
my $name = shift;
if ( ref($ref) eq 'Regexp' ) {
return;
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head1 TYPE-SPECIFIC ASSERTIONS
=head2 assert_datetime( $date )
Asserts that C<$date> is a DateTime object.
=cut
sub assert_datetime($;$) {
my $ref = shift;
my $name = shift;
if ( ref($ref) eq 'DateTime' || (Scalar::Util::blessed( $ref ) && $ref->isa( 'DateTime' )) ) {
return;
}
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head1 SET AND HASH MEMBERSHIP
=head2 assert_in( $string, \@inlist [,$name] );
Asserts that I<$string> matches one of the elements of I<\@inlist>.
I<$string> may be undef.
I<\@inlist> must be an array reference of non-ref strings. If any
element is a reference, the assertion fails.
=cut
sub assert_in($$;$) {
my $needle = shift;
my $haystack = shift;
my $name = shift;
my $found = 0;
# String has to be a non-ref scalar, or undef.
if ( !ref($needle) ) {
# Target list has to be an array...
if ( ref($haystack) eq 'ARRAY' || (Scalar::Util::blessed( $haystack ) && $haystack->isa( 'ARRAY' )) ) {
# ... and all elements have to be non-refs.
my $elements_ok = 1;
foreach my $element (@{$haystack}) {
if ( ref($element) ) {
$elements_ok = 0;
last;
}
}
# Now we can actually do the search.
if ( $elements_ok ) {
if ( defined($needle) ) {
foreach my $element (@{$haystack}) {
if ( $needle eq $element ) {
$found = 1;
last;
}
}
}
else {
foreach my $element (@{$haystack}) {
if ( !defined($element) ) {
$found = 1;
last;
}
}
}
}
}
}
return if $found;
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_exists( \%hash, $key [,$name] )
=head2 assert_exists( \%hash, \@keylist [,$name] )
Asserts that I<%hash> is indeed a hash, and that I<$key> exists in
I<%hash>, or that all of the keys in I<@keylist> exist in I<%hash>.
assert_exists( \%custinfo, 'name', 'Customer has a name field' );
assert_exists( \%custinfo, [qw( name addr phone )],
'Customer has name, address and phone' );
=cut
sub assert_exists($$;$) {
my $hash = shift;
my $key = shift;
my $name = shift;
my $ok = 0;
if ( ref($hash) eq 'HASH' || (Scalar::Util::blessed( $hash ) && $hash->isa( 'HASH' )) ) {
if ( defined($key) ) {
if ( ref($key) eq 'ARRAY' ) {
$ok = (@{$key} > 0);
for ( @{$key} ) {
if ( !exists( $hash->{$_} ) ) {
$ok = 0;
last;
}
}
}
elsif ( !ref($key) ) {
$ok = exists( $hash->{$key} );
}
else {
$ok = 0;
}
}
}
return if $ok;
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_lacks( \%hash, $key [,$name] )
=head2 assert_lacks( \%hash, \@keylist [,$name] )
Asserts that I<%hash> is indeed a hash, and that I<$key> does NOT exist
in I<%hash>, or that none of the keys in I<@keylist> exist in I<%hash>.
The list C<@keylist> cannot be empty.
assert_lacks( \%users, 'root', 'Root is not in the user table' );
assert_lacks( \%users, [qw( root admin nobody )], 'No bad usernames found' );
=cut
sub assert_lacks($$;$) {
my $hash = shift;
my $key = shift;
my $name = shift;
my $ok = 0;
if ( ref($hash) eq 'HASH' || (Scalar::Util::blessed( $hash ) && $hash->isa( 'HASH' )) ) {
if ( defined($key) ) {
if ( ref($key) eq 'ARRAY' ) {
$ok = (@{$key} > 0);
for ( @{$key} ) {
if ( exists( $hash->{$_} ) ) {
$ok = 0;
last;
}
}
}
elsif ( !ref($key) ) {
$ok = !exists( $hash->{$key} );
}
else {
$ok = 0;
}
}
}
return if $ok;
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_all_keys_in( \%hash, \@names [, $name ] )
Asserts that each key in C<%hash> is in the list of C<@names>.
This is used to ensure that there are no extra keys in a given hash.
assert_all_keys_in( $obj, [qw( height width depth )], '$obj can only contain height, width and depth keys' );
You can pass an empty list of C<@names>.
=cut
sub assert_all_keys_in($$;$) {
my $hash = shift;
my $keys = shift;
my $name = shift;
my @why;
my $ok = 0;
if ( ref($hash) eq 'HASH' || (Scalar::Util::blessed( $hash ) && $hash->isa( 'HASH' )) ) {
if ( ref($keys) eq 'ARRAY' ) {
$ok = 1;
my %keys = map { $_ => 1 } @{$keys};
for my $key ( keys %{$hash} ) {
if ( !exists $keys{$key} ) {
$ok = 0;
push @why, qq{Key "$key" is not a valid key.};
}
}
}
else {
push @why, 'Argument for array of keys is not an arrayref.';
}
}
else {
push @why, 'Argument for hash is not a hashref.';
}
return if $ok;
require Carp;
&Carp::confess( _failure_msg($name, @why) );
}
=head2 assert_keys_are( \%hash, \@keys [, $name ] )
Asserts that the keys for C<%hash> are exactly C<@keys>, no more and no less.
=cut
sub assert_keys_are($$;$) {
my $hash = shift;
my $keys = shift;
my $name = shift;
my @why;
my $ok = 0;
if ( ref($hash) eq 'HASH' || (Scalar::Util::blessed( $hash ) && $hash->isa( 'HASH' )) ) {
if ( ref($keys) eq 'ARRAY' ) {
my %keys = map { $_ => 1 } @{$keys};
# First check all the keys are allowed.
$ok = 1;
for my $key ( keys %{$hash} ) {
if ( !exists $keys{$key} ) {
$ok = 0;
push @why, qq{Key "$key" is not a valid key.};
}
}
# Now check that all the valid keys are represented.
for my $key ( @{$keys} ) {
if ( !exists $hash->{$key} ) {
$ok = 0;
push @why, qq{Key "$key" is not in the hash.};
}
}
}
else {
push @why, 'Argument for array of keys is not an arrayref.';
}
}
else {
push @why, 'Argument for hash is not a hashref.';
}
return if $ok;
require Carp;
&Carp::confess( _failure_msg($name, @why) );
}
=head1 CONTEXT ASSERTIONS
=head2 assert_context_nonvoid( [$name] )
Verifies that the function currently being executed has not been called
in void context. This is to ensure the calling function is not ignoring
the return value of the executing function.
Given this function:
sub something {
...
assert_context_nonvoid();
return $important_value;
}
These calls to C<something> will pass:
my $val = something();
my @things = something();
but this will fail:
something();
If the C<$name> argument is not passed, a default message of "<funcname>
must not be called in void context" is provided.
=cut
sub assert_context_nonvoid(;$) {
my (undef, undef, undef, $subroutine, undef, $wantarray) = caller(1);
return if defined($wantarray);
my $name = $_[0] // "$subroutine must not be called in void context";
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_context_void( [$name] )
Verifies that the function currently being executed has been called
in void context. This is for functions that do not return anything
meaningful.
Given this function:
sub something {
...
assert_context_void();
return; # No meaningful value.
}
These calls to C<something> will fail:
my $val = something();
my @things = something();
but this will pass:
something();
If the C<$name> argument is not passed, a default message of "<funcname>
must be called in void context" is provided.
=cut
sub assert_context_void(;$) {
my (undef, undef, undef, $subroutine, undef, $wantarray) = caller(1);
return if not defined($wantarray);
my $name = $_[0] // "$subroutine must be called in void context";
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_context_scalar( [$name] )
Verifies that the function currently being executed has been called in
scalar context. This is to ensure the calling function is not ignoring
the return value of the executing function.
Given this function:
sub something {
...
assert_context_scalar();
return $important_value;
}
This call to C<something> will pass:
my $val = something();
but these will fail:
something();
my @things = something();
If the C<$name> argument is not passed, a default message of "<funcname>
must be called in scalar context" is provided.
=cut
sub assert_context_scalar(;$) {
my (undef, undef, undef, $subroutine, undef, $wantarray) = caller(1);
return if defined($wantarray) && !$wantarray;
my $name = $_[0] // "$subroutine must be called in scalar context";
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head2 assert_context_list( [$name] )
Verifies that the function currently being executed has been called in
list context.
Given this function:
sub something {
...
assert_context_scalar();
return @values;
}
This call to C<something> will pass:
my @vals = something();
but these will fail:
something();
my $thing = something();
If the C<$name> argument is not passed, a default message of "<funcname>
must be called in list context" is provided.
=cut
sub assert_context_list(;$) {
my (undef, undef, undef, $subroutine, undef, $wantarray) = caller(1);
return if $wantarray;
my $name = shift // "$subroutine must be called in list context";
require Carp;
&Carp::confess( _failure_msg($name) );
}
=head1 UTILITY ASSERTIONS
=head2 assert_fail( [$name] )
Assertion that always fails. C<assert_fail($msg)> is exactly the same
as calling C<assert(0,$msg)>, but it eliminates that case where you
accidentally use C<assert($msg)>, which of course never fires.
=cut
sub assert_fail(;$) {
require Carp;
&Carp::confess( _failure_msg($_[0]) );
}
# Can't call confess() here or the stack trace will be wrong.
sub _failure_msg {
my ($name, @why) = @_;
my $msg = 'Assertion';
$msg .= " ($name)" if defined $name;
$msg .= " failed!\n";
$msg .= "$_\n" for @why;
return $msg;
}
=head1 COPYRIGHT & LICENSE
Copyright 2005-2025 Andy Lester
This program is free software; you can redistribute it and/or modify
it under the terms of the Artistic License version 2.0.
=head1 ACKNOWLEDGEMENTS
Thanks to
Eric A. Zarko,
Bob Diss,
Pete Krawczyk,
David Storrs,
Dan Friedman,
Allard Hoeve,
Thomas L. Shinnick,
and Leland Johnson
for code and fixes.
=cut
1;