NAME
Test::ClassAPI - Provides basic first-pass API testing for large class
trees
DESCRIPTION
For many APIs with large numbers of classes, it can be very useful to be
able to do a quick once-over to make sure that classes, methods, and
inheritance is correct, before doing more comprehensive testing. This
module aims to provide such a capability.
Using Test::ClassAPI
Test::ClassAPI is used with a fairly standard looking test script, with
the API description contained in a __DATA__ section at the end of the
script.
#!/usr/bin/perl
# Test the API for Foo::Bar
use strict;
use Test::More 'tests' => 123; # Optional
use Test::ClassAPI;
# Load the API to test
use Foo::Bar;
# Execute the tests
Test::ClassAPI->execute;
__DATA__
Foo::Bar::Thing=interface
Foo::Bar::Object=abstract
Foo::Bar::Planet=class
[Foo::Bar::Thing]
foo=method
[Foo::Bar::Object]
bar=method
whatsit=method
[Foo::Bar::Planet]
Foo::Bar::Object=isa
Foo::Bar::Thing=isa
blow_up=method
freeze=method
thaw=method
Looking at the test script, the code itself is fairly simple. We first
load Test::More and Test::ClassAPI. The loading and specification of a
test plan is optional, Test::ClassAPI will provide a plan automatically
if needed.
This is followed by a compulsory __DATA__ section, containing the API
description. This description is in provided in the general form of a
Windows style .ini file and is structured as follows.
Class Manifest
At the beginning of the file, in the root section of the config file, is
a list of entries where the key represents a class name, and the value
is one of either 'class', 'abstract', or 'interface'.
The 'class' entry indicates a fully fledged class. That is, the class is
tested to ensure it has been loaded, and the existance of every method
listed in the section ( and its superclasses ) is tested for.
The 'abstract' entry indicates an abstract class, one which is part of
our class tree, and needs to exist, but is never instantiated directly,
and thus does not have to itself implement all of the methods listed for
it. Generally, many individual 'class' entries will inherit from an
'abstract', and thus a method listed in the abstract's section will be
tested for in all the subclasses of it.
The 'interface' entry indicates an external interface that is not part
of our class tree, but is inherited from by one or more of our classes,
and thus the methods listed in the interface's section are tested for in
all the classes that inherit from it. For example, if a class inherits
from, and implements, the File::Handle interface, a
"File::Handle=interface" entry could be added, with the "[File::Handle]"
section listing all the methods in File::Handle that our class tree
actually cares about. No tests, for class or method existance, are done
on the interface itself.
Class Sections
Every class listed in the class manifest MUST have an individual
section, indicated by "[Class::Name]" and containing a set of entries
where the key is the name of something to test, and the value is the
type of test for it.
The 'isa' test checks inheritance, to make sure that the class the
section is for is (by some path) a sub-class of something else. This
does not have to be an immediate sub-class. Any class refered to
(recursively) in a 'isa' test will have its 'method' test entries
applied to the class as well.
The 'method' test is a simple method existance test, using
"UNIVERSAL::can" to make sure that the method exists in the class.
METHODS
execute
The "Test::ClassAPI" has a single method, "execute" which is used to
start the testing process. It accepts a single option argument,
'complete', which indicates to the testing process that the API listed
should be considered a complete list of the entire API. This enables an
additional test for each class to ensure that every public method in the
class is detailed in the API description, and that nothing has been
"missed".
SUPPORT
Bugs should be submitted via the CPAN bug tracker, located at
<
http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Test-ClassAPI>
For other issues, or commercial enhancement or support, contact the
author.
AUTHOR
Adam Kennedy <
[email protected]>
COPYRIGHT
Copyright 2002 - 2007 Adam Kennedy.
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
The full text of the license can be found in the LICENSE file included
with this module.
