# Carp::Assert::More [![Build Status](https://github.com/petdance/carp-assert-more/workflows/testsuite/badge.svg?branch=dev)](https://github.com/petdance/carp-assert-more/actions?query=workflow%3Atestsuite+branch%3Adev) # NAME Carp::Assert::More - convenience wrappers around Carp::Assert # VERSION Version 1.20 # 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' ); # DESCRIPTION Carp::Assert::More is a set of wrappers around the [Carp::Assert](https://metacpan.org/pod/Carp::Assert) functions to make the habit of writing assertions even easier. Everything in here is effectively syntactic sugar. There's no technical reason to use assert_isa( $foo, 'HTML::Lint' ); instead of assert( defined $foo ); assert( ref($foo) eq 'HTML::Lint' ); other than readability and simplicity of the code. My intent here is to make common assertions easy so that we as programmers have no excuse to not use them. # CAVEATS I haven't specifically done anything to make Carp::Assert::More be backwards compatible with anything besides Perl 5.6.1, much less back to 5.004. Perhaps someone with better testing resources in that area can help me out here. # SIMPLE ASSERTIONS ## assert\_is( $string, $match \[,$name\] ) Asserts that _$string_ matches _$match_. ## assert\_isnt( $string, $unmatch \[,$name\] ) Asserts that _$string_ does NOT match _$unmatch_. ## assert\_like( $string, qr/regex/ \[,$name\] ) Asserts that _$string_ matches _qr/regex/_. The assertion fails either the string or the regex are undef. ## assert\_unlike( $string, qr/regex/ \[,$name\] ) Asserts that _$string_ matches _qr/regex/_. The assertion fails if the regex is undef. ## assert\_defined( $this \[, $name\] ) Asserts that _$this_ is defined. ## assert\_undefined( $this \[, $name\] ) Asserts that _$this_ is not defined. ## assert\_nonblank( $this \[, $name\] ) Asserts that _$this_ is not blank and not a reference. # NUMERIC ASSERTIONS ## assert\_numeric( $n \[, $name\] ) Asserts that `$n` looks like a number, according to `Scalar::Util::looks_like_number`. ## assert\_integer( $this \[, $name \] ) Asserts that _$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 ## assert\_nonzero( $this \[, $name \] ) Asserts that the numeric value of _$this_ is not zero. assert_nonzero( 0 ); # FAIL assert_nonzero( -14 ); # pass assert_nonzero( '14.' ); # pass Asserts that the numeric value of _$this_ is not zero. ## assert\_positive( $this \[, $name \] ) Asserts that the numeric value of _$this_ is greater than zero. assert_positive( 0 ); # FAIL assert_positive( -14 ); # FAIL assert_positive( '14.' ); # pass ## assert\_nonnegative( $this \[, $name \] ) Asserts that the numeric value of _$this_ is greater than or equal to zero. Since non-numeric strings evaluate to zero, this means that any non-numeric string will pass. assert_nonnegative( 0 ); # pass assert_nonnegative( -14 ); # FAIL assert_nonnegative( '14.' ); # pass assert_nonnegative( 'dog' ); # pass ## assert\_negative( $this \[, $name \] ) Asserts that the numeric value of _$this_ is less than zero. assert_negative( 0 ); # FAIL assert_negative( -14 ); # pass assert_negative( '14.' ); # FAIL ## assert\_nonzero\_integer( $this \[, $name \] ) Asserts that the numeric value of _$this_ is not zero, and that _$this_ is an integer. assert_nonzero_integer( 0 ); # FAIL assert_nonzero_integer( -14 ); # pass assert_nonzero_integer( '14.' ); # FAIL ## assert\_positive\_integer( $this \[, $name \] ) Asserts that the numeric value of _$this_ is greater than zero, and that _$this_ is an integer. assert_positive_integer( 0 ); # FAIL assert_positive_integer( -14 ); # FAIL assert_positive_integer( '14.' ); # FAIL assert_positive_integer( '14' ); # pass ## assert\_nonnegative\_integer( $this \[, $name \] ) Asserts that the numeric value of _$this_ is not less than zero, and that _$this_ is an integer. assert_nonnegative_integer( 0 ); # pass assert_nonnegative_integer( -14 ); # pass assert_nonnegative_integer( '14.' ); # FAIL ## assert\_negative\_integer( $this \[, $name \] ) Asserts that the numeric value of _$this_ is less than zero, and that _$this_ is an integer. assert_negative_integer( 0 ); # FAIL assert_negative_integer( -14 ); # pass assert_negative_integer( '14.' ); # FAIL # REFERENCE ASSERTIONS ## assert\_isa( $this, $type \[, $name \] ) Asserts that _$this_ is an object of type _$type_. ## assert\_isa\_in( $obj, \\@types \[, $description\] ) Assert that the blessed `$obj` isa one of the types in `\@types`. assert_isa_in( $obj, [ 'My::Foo', 'My::Bar' ], 'Must pass either a Foo or Bar object' ); ## assert\_empty( $this \[, $name \] ) _$this_ must be a ref to either a hash or an array. Asserts that that collection contains no elements. Will assert (with its own message, not _$name_) unless given a hash or array ref. It is OK if _$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 ## assert\_nonempty( $this \[, $name \] ) _$this_ must be a ref to either a hash or an array. Asserts that that collection contains at least 1 element. Will assert (with its own message, not _$name_) unless given a hash or array ref. It is OK if _$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 ## assert\_nonref( $this \[, $name \] ) Asserts that _$this_ is not undef and not a reference. ## assert\_hashref( $ref \[,$name\] ) Asserts that _$ref_ is defined, and is a reference to a (possibly empty) hash. **NB:** This method returns _false_ for objects, even those whose underlying data is a hashref. This is as it should be, under the assumptions that: - (a) you shouldn't rely on the underlying data structure of a particular class, and - (b) you should use `assert_isa` instead. ## assert\_arrayref( $ref \[, $name\] ) ## assert\_listref( $ref \[,$name\] ) Asserts that _$ref_ is defined, and is a reference to a (possibly empty) list. **NB:** The same caveat about objects whose underlying structure is a hash (see `assert_hashref`) applies here; this method returns false even for objects whose underlying structure is an array. `assert_listref` is an alias for `assert_arrayref` and may go away in the future. Use `assert_arrayref` instead. ## assert\_aoh( $ref \[, $name \] ) Verifies that `$array` is an arrayref, and that every element is a hashref. The array `$array` can be an empty arraref and the assertion will pass. ## assert\_coderef( $ref \[,$name\] ) Asserts that _$ref_ is defined, and is a reference to a closure. # TYPE-SPECIFIC ASSERTIONS ## assert\_datetime( $date ) Asserts that `$date` is a DateTime object. # SET AND HASH MEMBERSHIP ## assert\_in( $string, \\@inlist \[,$name\] ); Asserts that _$string_ is defined and matches one of the elements of _\\@inlist_. _\\@inlist_ must be an array reference of defined strings. ## assert\_exists( \\%hash, $key \[,$name\] ) ## assert\_exists( \\%hash, \\@keylist \[,$name\] ) Asserts that _%hash_ is indeed a hash, and that _$key_ exists in _%hash_, or that all of the keys in _@keylist_ exist in _%hash_. assert_exists( \%custinfo, 'name', 'Customer has a name field' ); assert_exists( \%custinfo, [qw( name addr phone )], 'Customer has name, address and phone' ); ## assert\_lacks( \\%hash, $key \[,$name\] ) ## assert\_lacks( \\%hash, \\@keylist \[,$name\] ) Asserts that _%hash_ is indeed a hash, and that _$key_ does NOT exist in _%hash_, or that none of the keys in _@keylist_ exist in _%hash_. assert_lacks( \%users, 'root', 'Root is not in the user table' ); assert_lacks( \%users, [qw( root admin nobody )], 'No bad usernames found' ); ## assert\_all\_keys\_in( \\%hash, \\@names \[, $name \] ) Asserts that each key in `%hash` is in the list of `@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' ); # UTILITY ASSERTIONS ## assert\_fail( \[$name\] ) Assertion that always fails. `assert_fail($msg)` is exactly the same as calling `assert(0,$msg)`, but it eliminates that case where you accidentally use `assert($msg)`, which of course never fires. # COPYRIGHT & LICENSE Copyright 2005-2019 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. # 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.