Provided by: libtest-spec-perl_0.54-2_all 
NAME
Test::Spec - Write tests in a declarative specification style
SYNOPSIS
use Test::Spec; # automatically turns on strict and warnings
describe "A date" => sub {
my $date;
describe "in a leap year" => sub {
before each => sub {
$date = DateTime->new(year => 2000, month => 2, day => 28);
};
it "should know that it is in a leap year" => sub {
ok($date->is_leap_year);
};
it "should recognize Feb. 29" => sub {
is($date->add(days => 1)->day, 29);
};
};
describe "not in a leap year" => sub {
before each => sub {
$date = DateTime->new(year => 2001, month => 2, day => 28);
};
it "should know that it is NOT in a leap year" => sub {
ok(!$date->is_leap_year);
};
it "should NOT recognize Feb. 29" => sub {
is($date->add(days => 1)->day, 1);
};
};
};
runtests unless caller;
# Generates the following output:
# ok 1 - A date in a leap year should know that it is in a leap year
# ok 2 - A date in a leap year should recognize Feb. 29
# ok 3 - A date not in a leap year should know that it is NOT in a leap year
# ok 4 - A date not in a leap year should NOT recognize Feb. 29
# 1..4
DESCRIPTION
This is a declarative specification-style testing system for behavior-driven development (BDD) in Perl.
The tests (a.k.a. examples) are named with strings instead of subroutine names, so your fingers will
suffer less fatigue from underscore-itis, with the side benefit that the test reports are more legible.
This module is inspired by and borrows heavily from RSpec <http://rspec.info/documentation>, a BDD tool
for the Ruby programming language.
EXPORTS
When given no list (i.e. "use Test::Spec;"), this class will export:
• Spec definition functions
These are the functions you will use to define behaviors and run your specs: "describe", "it",
"they", "before", "after", "runtests", "share", "shared_examples_for", "it_should_behave_like", and
"spec_helper".
• The stub/mock functions in Test::Spec::Mocks.
• Everything that Test::More normally exports
This includes "ok", "is" and friends. You'll use these to assert correct behavior.
• Everything that Test::Deep normally exports
More assertions including "cmp_deeply".
• Everything that "Test::Trap" normally exports
The "trap()" function, which let you test behaviors that call "exit()" and other hard things like
that. "A block eval on steroids."
If you specify an import list, only functions directly from "Test::Spec" (those documented below) are
available.
FUNCTIONS
runtests
runtests(@patterns)
Runs all the examples whose descriptions match one of the (non case-sensitive) regular expressions in
@patterns. If @patterns is not provided, runs all examples. The environment variable "SPEC" will be
used as a default pattern if present.
If called as a function (i.e. not a method call with "->"), "runtests" will autodetect the package
from which it is called and run that package's examples. A useful idiom is:
runtests unless caller;
which will run the examples when the file is loaded as a script (for example, by running it from the
command line), but not when it is loaded as a module (with "require" or "use").
describe DESCRIPTION => CODE
describe CODE
Defines a specification context under which examples and more descriptions can be defined. All
examples must come inside a "describe" block.
"describe" blocks can be nested to DRY up your specs.
For large specifications, "describe" blocks can save you a lot of duplication:
describe "A User object" => sub {
my $user;
before sub {
$user = User->new;
};
describe "from a web form" => sub {
before sub {
$user->init_from_tree({ username => "bbill", ... });
};
it "should read its attributes from the form";
describe "when saving" => sub {
it "should require a unique username";
it "should require a password";
};
};
};
The setup work done in each "before" block cascades from one level to the next, so you don't have
to make a call to some initialization function manually in each test. It's done automatically
based on context.
Using describe blocks improves legibility without requiring more typing.
The name of the context will be included by default in the success/failure report generated by
Test::Builder-based testing methods (e.g. Test::More's ok() function). For an example like
this:
describe "An unladen swallow" => sub {
it "has an airspeed of 11 meters per second" => sub {
is($swallow->airspeed, "11m/s");
};
};
The output generated is:
ok 1 - An unladen swallow has an airspeed of 11 meters per second
Contrast this to the following test case to generate the same output:
sub unladen_swallow_airspeed : Test {
is($swallow->airspeed, "11m/s",
"An unladen swallow has an airspeed of 11 meters per second");
}
"describe" blocks execute in the order in which they are defined. Multiple "describe" blocks with the
same name are allowed. They do not replace each other, rather subsequent "describe"s extend the
existing one of the same name.
context
An alias for "describe()".
xdescribe
Specification contexts may be disabled by calling "xdescribe" instead of "describe()". All examples
inside an "xdescribe" are reported as "# TODO (disabled)", which prevents Test::Harness/prove from
counting them as failures.
xcontext
An alias for "xdescribe()".
it SPECIFICATION => CODE
it CODE
it TODO_SPECIFICATION
Defines an example to be tested. Despite its awkward name, "it" allows a natural (in my opinion) way
to describe expected behavior:
describe "A captive of Buffalo Bill" => sub {
it "puts the lotion on its skin" => sub {
...
};
it "puts the lotion in the basket"; # TODO
};
If a code reference is not passed, the specification is assumed to be unimplemented and will be
reported as "TODO (unimplemented)" in the test results (see "todo_skip" in Test::Builder. TODO tests
report as skipped, not failed.
they SPECIFICATION => CODE
they CODE
they TODO_SPECIFICATION
An alias for "it". This is useful for describing behavior for groups of items, so the verb agrees
with the noun:
describe "Captives of Buffalo Bill" => sub {
they "put the lotion on their skin" => sub {
...
};
they "put the lotion in the basket"; # TODO
};
xit/xthey
Examples may be disabled by calling xit()/xthey() instead of it()/they(). These examples are
reported as "# TODO (disabled)", which prevents Test::Harness/prove from counting them as failures.
before each => CODE
before all => CODE
before CODE
Defines code to be run before tests in the current describe block are run. If "each" is specified,
CODE will be re-executed for every test in the context. If "all" is specified, CODE will only be
executed before the first test.
The default is "each", due to this logic presented in RSpec's documentation:
"It is very tempting to use before(:all) and after(:all) for situations in which it is not
appropriate. before(:all) shares some (not all) state across multiple examples. This means that the
examples become bound together, which is an absolute no-no in testing. You should really only ever
use before(:all) to set up things that are global collaborators but not the things that you are
describing in the examples.
The most common cases of abuse are database access and/or fixture setup. Every example that accesses
the database should start with a clean slate, otherwise the examples become brittle and start to lose
their value with false negatives and, worse, false positives."
(<http://rspec.info/documentation/before_and_after.html>)
There is no restriction on having multiple before blocks. They will run in sequence within their
respective "each" or "all" groups. "before "all"" blocks run before "before "each"" blocks.
after each => CODE
after all => CODE
after CODE
Like "before", but backwards. Runs CODE after each or all tests, respectively. The default is
"each".
"after "all"" blocks run after "after "each"" blocks.
around CODE
Defines code to be run around tests in the current describe block are run. This code must call
"yield"..
our $var = 0;
describe "Something" => sub {
around {
local $var = 1;
yield;
};
it "should have localized var" => sub {
is $var, 1;
};
};
This CODE will run around each example.
yield
Runs examples in context of "around" block.
shared_examples_for DESCRIPTION => CODE
Defines a group of examples that can later be included in "describe" blocks or other
"shared_examples_for" blocks. See "Shared example groups".
Example group names are global, but example groups can be defined at any level (i.e. they can be
defined in the global context, or inside a "describe" block).
my $browser;
shared_examples_for "all browsers" => sub {
it "should open a URL" => sub { ok($browser->open("http://www.google.com/")) };
...
};
describe "Firefox" => sub {
before all => sub { $browser = Firefox->new };
it_should_behave_like "all browsers";
it "should have firefox features";
};
describe "Safari" => sub {
before all => sub { $browser = Safari->new };
it_should_behave_like "all browsers";
it "should have safari features";
};
it_should_behave_like DESCRIPTION
Asserts that the thing currently being tested passes all the tests in the example group identified by
DESCRIPTION (having previously been defined with a "shared_examples_for" block). In essence, this is
like copying all the tests from the named "shared_examples_for" block into the current context. See
"Shared example groups" and shared_examples_for.
share %HASH
Registers %HASH for sharing data between tests and example groups. This lets you share variables
with code in different lexical scopes without resorting to using package (i.e. global) variables or
jumping through other hoops to circumvent scope problems.
Every hash that is "share"d refers to the same data. Sharing a hash will make its existing contents
inaccessible, because afterwards it contains the same data that all other shared hashes contain. The
result is that you get a hash with global semantics but with lexical scope (assuming %HASH is a
lexical variable).
There are a few benefits of using "share" over using a "regular" global hash. First, you don't have
to decide what package the hash will belong to, which is annoying when you have specs in several
packages referencing the same shared examples. You also don't have to clutter your examples with
colons for fully-qualified names. For example, at my company our specs go in the "ICA::TestCase"
hierarchy, and "$ICA::TestCase::Some::Package::variable" is exhausting to both the eyes and the
hands. Lastly, using "share" allows "Test::Spec" to provide this functionality without deciding on
the variable name for you (and thereby potentially clobbering one of your variables).
share %vars; # %vars now refers to the global share
share my %vars; # declare and share %vars in one step
spec_helper FILESPEC
Loads the Perl source in "FILESPEC" into the current spec's package. If "FILESPEC" is relative (no
leading slash), it is treated as relative to the spec file (i.e. not the currently running script).
This lets you keep helper scripts near the specs they are used by without exercising your File::Spec
skills in your specs.
# in foo/spec.t
spec_helper "helper.pl"; # loads foo/helper.pl
spec_helper "helpers/helper.pl"; # loads foo/helpers/helper.pl
spec_helper "/path/to/helper.pl"; # loads /path/to/helper.pl
Shared example groups
This feature comes straight out of RSpec, as does this documentation:
You can create shared example groups and include those groups into other groups.
Suppose you have some behavior that applies to all editions of your product, both large and small.
First, factor out the "shared" behavior:
shared_examples_for "all editions" => sub {
it "should behave like all editions" => sub {
...
};
};
then when you need to define the behavior for the Large and Small editions, reference the shared behavior
using the "it_should_behave_like()" function.
describe "SmallEdition" => sub {
it_should_behave_like "all editions";
};
describe "LargeEdition" => sub {
it_should_behave_like "all editions";
it "should also behave like a large edition" => sub {
...
};
};
"it_should_behave_like" will search for an example group by its description string, in this case, "all
editions".
Shared example groups may be included in other shared groups:
shared_examples_for "All Employees" => sub {
it "should be payable" => sub {
...
};
};
shared_examples_for "All Managers" => sub {
it_should_behave_like "All Employees";
it "should be bonusable" => sub {
...
};
};
describe Officer => sub {
it_should_behave_like "All Managers";
it "should be optionable";
};
# generates:
ok 1 - Officer should be optionable
ok 2 - Officer should be bonusable
ok 3 - Officer should be payable
Refactoring into files
If you want to factor specs into separate files, variable scopes can be tricky. This is especially true
if you follow the recommended pattern and give each spec its own package name. "Test::Spec" offers a
couple of functions that ease this process considerably: share and spec_helper.
Consider the browsers example from "shared_examples_for". A real browser specification would be large, so
putting the specs for all browsers in the same file would be a bad idea. So let's say we create
"all_browsers.pl" for the shared examples, and give Safari and Firefox "safari.t" and "firefox.t",
respectively.
The problem then becomes: how does the code in "all_browsers.pl" access the $browser variable? In the
example code, $browser is a lexical variable that is in scope for all the examples. But once those
examples are split into multiple files, you would have to use either package global variables or worse,
come up with some other hack. This is where "share" and "spec_helper" come in.
# safari.t
package Testcase::Safari;
use Test::Spec;
spec_helper 'all_browsers.pl';
describe "Safari" => sub {
share my %vars;
before all => sub { $vars{browser} = Safari->new };
it_should_behave_like "all browsers";
it "should have safari features";
};
# firefox.t
package Testcase::Firefox;
use Test::Spec;
spec_helper 'all_browsers.pl';
describe "Firefox" => sub {
share my %vars;
before all => sub { $vars{browser} = Firefox->new };
it_should_behave_like "all browsers";
it "should have firefox features";
};
# in all_browsers.pl
shared_examples_for "all browsers" => sub {
# doesn't have to be the same name!
share my %t;
it "should open a URL" => sub {
ok $t{browser}->open("http://www.google.com/");
};
...
};
Order of execution
This example, shamelessly adapted from the RSpec website, gives an overview of the order in which
examples run, with particular attention to "before" and "after".
describe Thing => sub {
before all => sub {
# This is run once and only once, before all of the examples
# and before any before("each") blocks.
};
before each => sub {
# This is run before each example.
};
before sub {
# "each" is the default, so this is the same as before("each")
};
it "should do stuff" => sub {
...
};
it "should do more stuff" => sub {
...
};
after each => sub {
# this is run after each example
};
after sub {
# "each" is the default, so this is the same as after("each")
};
after all => sub {
# this is run once and only once after all of the examples
# and after any after("each") blocks
};
};
SEE ALSO
RSpec <http://rspec.info>, Test::More, Test::Deep, Test::Trap, Test::Builder.
The mocking and stubbing tools are in Test::Spec::Mocks.
AUTHOR
Philip Garrett <philip.garrett@icainformatics.com>
CONTRIBUTING
The source code for Test::Spec lives on github <https://github.com/kingpong/perl-Test-Spec>
If you want to contribute a patch, fork my repository, make your change, and send me a pull request.
SUPPORT
If you have found a defect or have a feature request please report an issue at
https://github.com/kingpong/perl-Test-Spec/issues. For help using the module, standard Perl support
channels like Stack Overflow <http://stackoverflow.com/> and comp.lang.perl.misc
<http://groups.google.com/group/comp.lang.perl.misc> are probably your best bet.
COPYRIGHT & LICENSE
Copyright (c) 2010-2011 by Informatics Corporation of America.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl
itself.
perl v5.34.0 2022-06-28 Test::Spec(3pm)