NAME

Test::Roo::DataDriven - simple data-driven tests with Test::Roo

VERSION

version v0.4.2

SYNOPSIS

package MyTests

use Test::Roo;

use lib 't/lib';

with qw/
  MyClass::Test::Role
  Test::Roo::DataDriven
  /;

1;

package main;

use Test::More;

MyTests->run_data_tests(
  files   => 't/data/myclass',
  recurse => 1,
);

done_testing;

DESCRIPTION

This class extends Test::Roo for data-driven tests that are kept in separate files.

This is useful when a test script has too many test cases, so that it is impractical to include all of the cases in a single test script.

It allows different tests to share the test cases.

It also makes it easier to have testers with very little Perl knowledge to write tests.

METHODS

run_data_tests

This is called as a class method, and is a wrapper around the run_tests method. It takes the following arguments:

• files

  This is a path or array reference to a list of paths that contain test cases.

  If a path is a directory, then all test cases in that directory will be tested.

  The files are expected to be executable Perl snippets that return a hash reference or an array reference of hash references. The keys should correspond to the attributes of the Test::Roo class.

  See "Data Files" below.

• recurse

  When this is true, then any directories in "files" will be checked recursively.

  It is false by default.

  item follow_symlinks

  When this is true, then symlinks in "files" will be followed.

  It is false by default.

• match

  A regular expression to match the names of data files. It defaults to qr/\.dat$/.

• filter

  This is a reference to a subroutine that takes a single test case as a hash reference, as well as the data file (Path::Tiny) and case index in that file.

  The subroutine is expected to return a hash reference to a test case.

  For example, if you wanted to add the data file and index, you might use

  MyTests->run_data_tests(
    filter = sub {
        my ($test, $file, $index) = @_;
        my %args = (
            %$test,                # avoid side-effects
            data_file  => "$file", # stringify Path::Tiny
            data_index => $index,  # undef if none
        );
        return \%args;
    },
    ...
  );

• parser

  By default, the data files are Perl snippets. If the data files exist in a different format, then an alternative parser can be used.

  For example, if the data files were in JSON format:

  MyTests->run_data_tests(
    match  => qr/\.json$/,
    parser => sub { decode_json( $_[0]->slurp_raw ) },
  );

  Note that the argument is a Path::Tiny object.

  See the "parse_data_file" method.

  Added in v0.2.0.

• argv

  If any arguments are passed on the command line, then they are assumed to be directories are test files. Those will be tested instead of the "files" parameter.

  This allows you to run tests on specific data files or directories.

  For example,

  prove -lv t/01-example.t :: t/data/002-another.dat
  

  This is enabled by default, but requires App::Prove.

  Added in v0.2.3.

parse_data_file

my $data = $class->parse_data_file( $file );

This is the default parser for the "Data Files".

Added in v0.2.0.

Data Files

Unless the default "parser" is changed, the data files are simple Perl scripts that return a hash reference (or array reference of hash references) of constructor values for the Test::Roo class.

For example,

#!/perl

use Test::Deep;

+{
  description => 'Sample test',
  params => {
    choices => bag( qw/ first second / ),
    page    => 1,
  },
};

In the above example, we are using the bag function from Test::Deep, so we have to import the module into our test case to ensure that it compiles correctly.

Note that there is no performance loss in repeating module imports in every test case. However, you may want to use a module like ToolSet to import common packages.

Data files can contain multiple test cases:

#!/perl

use Test::Deep;

[

  {
    description => 'Sample test',
    params => {
      choices => bag( qw/ first second / ),
      page    => 1,
    },
  },

  {
    description => 'Another test',
    params => {
      choices => bag( qw/ second third / ),
      page    => 2,
    },
  },

];

The data files can also include scripts to generate test cases:

#!/perl

sub generate_cases {
  ...
};

[
  generate_cases( page => 1 ),
  generate_cases( page => 2 ),
];

Each data file is loaded into a unique namespace. However, there is nothing preventing the datafiles from modifying variables in other namespaces, or even doing anything else.

If the data file is successfully parsed, then the namespace is unloaded.

KNOWN ISSUES

See also "BUGS" below.

Skipping test cases

Skipping a test case in your test class as per Test::Roo::Cookbook, e.g.

sub BUILD {
  my ($self) = @_;

  ...

  plan skip_all => "Cannot test" if $some_condition;

}

will stop all remaining tests from running.

Instead, skip tests before the setup:

before setup => sub {
  my ($self) = @_;

  ...

  plan skip_all => "Cannot test" if $some_condition;

};

Prerequisite Scanners

Prerequisite scanners used for build tools may not recognise modules used in the "Data Files". To work around this, use the modules as well in the test class or explicitly add them to the distribution's metadata.

SEE ALSO

Test::Roo

SOURCE

The development version is on github at https://github.com/robrwo/Test-Roo-DataDriven and may be cloned from git://github.com/robrwo/Test-Roo-DataDriven.git

BUGS

Please report any bugs or feature requests on the bugtracker website https://github.com/robrwo/Test-Roo-DataDriven/issues

When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature.

AUTHOR

Robert Rothenberg rrwo@cpan.org

The initial development of this module was sponsored by Science Photo Library https://www.sciencephoto.com.

CONTRIBUTORS

• Aaron Crane arc@cpan.org
• Mohammad S Anwar mohammad.anwar@yahoo.com

COPYRIGHT AND LICENSE

This software is Copyright (c) 2017-2019 by Robert Rothenberg.

This is free software, licensed under:

The Artistic License 2.0 (GPL Compatible)