NAME
Test::BDD::Cucumber::Manual::Steps - How to write Step Definitions
VERSION
version 0.12
INTRODUCTION
The 'code' part of a Cucumber test-suite are the Step Definition files which match steps, and execute code based on them. This document aims to give you a quick overview of those.
STARTING OFF
Most of your step files will want to start something like:
#!perl
use strict;
use warnings;
use Test::More;
use Test::BDD::Cucumber::StepFile;
use Method::Signatures;
The fake shebang line gives some hints to syntax highlighters, and use strict;
and use warnings;
are hopefully fairly standard at this point.
Most of my Step Definition files make use of Test::More, but you can use any Test::Builder based testing module. Your step will pass its pass or fail status back to its harness via Test::Builder - each step is run as if it were its own tiny test file, with its own localized Test::Builder object.
Test::BDD::Cucumber::StepFile gives us the functions Given()
, When()
, Then()
and Step()
. These pass the step definitions to the class loading the step definitions, and specify which Step Verb should be used - Step()
matches any.
Method::Signatures allows us to use a small amount of syntactic sugar for the step definitions, and gives us the func()
keyword you'll see in a minute.
STEP DEFINITIONS
Given qr/I have (\d+)/, func ($c) {
$c->stash->{'scenario'}->{'count'} += $1;
}
When "The count is an integer", func ($c) {
$c->stash->{'scenario'}->{'count'} =
int( $c->stash->{'scenario'}->{'count'} );
}
Then qr/The count should be (\d+)/, func ($c) {
is( $c->stash->{'scenario'}->{'count'}, $c->matches->[0], "Count matches" );
}
Each of the exported verb functions accept a regular expression (or a string that's used as one), and a coderef. The coderef is passed a single argument, the Test::BDD::Cucumber::StepContext object. To make this a little prettier, we use Method::Signatures's func()
keyword so we're not continually typing: sub { my $c = shift; ...
.
We will evaluate the regex immediately before we execute the coderef, so you can use $1, $2, $etc, although these are also available via the StepContext.
NEXT STEPS
How step files are loaded is discussed in Test::BDD::Cucumber::Manual::Architecture, but isn't of much interest. Of far more interest should be seeing what you have available in Test::BDD::Cucumber::StepContext...
AUTHOR
Peter Sergeant pete@clueball.com
LICENSE
Copyright 2011, Peter Sergeant; Licensed under the same terms as Perl