Perl Language Perl Testing Perl Unit Testing Example
Example
The following is a simple example Perl test script, that gives some structure to allow for testing of other methods in the class/package under test. The script produces standard output with simple "ok" / "not ok" text, which is called TAP (Test Anything Protocol).
Typically the prove command runs the script(s) and summarises the test results.
#!/bin/env perl
# CPAN
use Modern::Perl;
use Carp;
use Test::More;
use Test::Exception;
use Const::Fast;
# Custom
BEGIN { use_ok('Local::MyPackage'); }
const my $PACKAGE_UNDER_TEST => 'Local::MyPackage';
# Example test of method 'file_type_build'
sub test_file_type_build {
my %arg = @_;
my $label = 'file_type_build';
my $got_file_type;
my $filename = '/etc/passwd';
# Check the method call lives
lives_ok(
sub {
$got_file_type = $PACKAGE_UNDER_TEST->file_type_build(
filename => $filename
);
},
"$label - lives"
);
# Check the result of the method call matches our expected result.
like( $got_file_type, qr{ASCII[ ]text}ix, "$label - result" );
return;
} ## end sub test_file_type_build
# More tests can be added here for method 'file_type_build', or other methods.
MAIN: {
subtest 'file_type_build' => sub {
test_file_type_build();
# More tests of the method can be added here.
done_testing();
};
# Tests of other methods can be added here, just like above.
done_testing();
} ## end MAIN:
Best Practice
A test script should only test one package/class, but there many scripts may be used to test a package/class.
Further Reading
- Test::More - The basic test operations.
- Test::Exception - Testing thrown exceptions.
- Test::Differences - Comparing test results that have complex data structures.
- Test::Class - Class based testing rather than script. Similarities to JUnit.
- Perl Testing Tutorials - Further reading.
