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Test::Builder zef:raku-community-modules last updated on 2022-05-24
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Test::Builder - flexible framework for building TAP test libraries


my $tb =;


$tb.ok(1, 'This is a test');
$tb.ok(1, 'This is another test');



`Test::Builder` is meant to serve as a generic backend for test libraries. Put differently, it provides the basic "building blocks" and generic functionality needed for building your own application-specific TAP test libraries.

`Test::Builder` conforms to the Test Anything Protocol (TAP) specification.


Object Initialization

### **new()**

Returns the `Test::Builder` singleton object.

The `new()` method only returns a new object the first time that it's called. If called again, it simply returns the same object. This allows multiple modules to share the global information about the TAP harness's state.

Alternatively, if a singleton object is too limiting, you can use the `create()` method instead.

### **create()**

Returns a new `Test::Builder` instance.

The `create()` method should only be used under certain circumstances. For instance, when testing `Test::Builder`-based modules. In all other cases, it is recommended that you stick to using `new()` instead.

Implementing Tests

The following methods are responsible for performing the actual tests.

All methods take an optional string argument describing the nature of the test.

### **plan(Int $tests)**

Declares how many tests are going to be run.

If called as `.plan(*)`, then a plan will not be set. However, it is your job to call `done()` when all tests have been run.

### **ok(Mu $test, Str $description)**

Evaluates `$test` in a boolean context. The test will pass if the expression evaluates to `Bool::True` and fail otherwise.

### **nok(Mu $test, Str $description)**

The antithesis of `ok()`. Evaluates `$test` in a boolean context. The test will pass if the expression evaluates to `Bool::False` and fail otherwise.

Modifying Test Behavior

### **todo(Str $reason, Int $count)**

Marks the next `$count` tests as failures but ignores the fact. Test execution will continue after displaying the message in `$reason`.

It's important to note that even though the tests are marked as failures, they will still be evaluated. If a test marked with `todo()` in fact passes, a warning message will be displayed.

# TODO The todo() method doesn't actually does this yet but I want it to




Kevin Polulak


`Test::Builder` was largely inspired by chromatic's work on the old `Test::Builder` module for Pugs.

Additionally, `Test::Builder` is based on the Perl module of the same name also written by chromatic and Michael G. Schwern.


Copyright 2011 Kevin Polulak

Copyright 2012 - 2022 Raku Community

This program is distributed under the terms of the Artistic License 2.0.