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The Official Raku Test Suite

The purpose of the test suite is to validate implementations that wish to be known as a conforming Raku.



Please consider this test suite to be the bleeding edge of Raku development. New tests, tests for proposed new features, etc., will live on this 'master' branch. Once a specification is cut, a branch will be created for that version of the spec, e.g., 6.c for Christmas language release. If errata becomes available, it will be kept in -errata branch for that specific language version, e.g. 6.c-errata for 6.c.

As they develop, different implementations will certainly be in different states of readiness with respect to the test suite, so in order for the various implementations to track their progress independently, we've established a mechanism for fudging the tests in a kind of failsoft fashion. To pass a test officially, an implementation must be able to run a test file unmodified, but an implementation may (temporarily) skip tests or mark them as "todo" via the fudging mechanism, which is implemented via the fudge preprocessor. Individual implementations are not allowed to modify the actual test code, but may insert line comments before each actual test (or block of tests) that changes how those tests are to be treated for this platform. The fudge preprocessor pays attention only to the comments that belong to the current implementation and ignores all the rest. If your implementation is named "rakudo" then your special comment lines look like:

#?rakudo: [NUM] VERB ARGS

(The colon is optional.)

The optional NUM says how many statements or blocks to apply the verb to. (If not supplied, a value of 1 is assumed). A statement is arbitrarily defined as one or more lines starting with a test call and ending in a semicolon (with an optional comment).

VERBs include:

skip "reason"	# skip test entirely
eval "reason"	# eval the test because it doesn't parse yet
try "reason"	# try the test because it throws exception
todo "reason"	# mark "todo" because "not ok" is expected
emit code		# insert code (such as "skip-rest();") inline

All fudged tests return an exit code of 1 by default, so the test harness will mark it as "dubious" even if all the tests supposedly pass.

You may also negate the test:

#!rakudo [NUM] VERB ARGS

This will apply the verb on any system that isn't rakudo.

Sometimes environment variables distinguish syntactic or semantic variants, so you may apply a verb depending on the presence or absence of such a setting:


The environment variable must be uppercase.

There is also the following directive which modifies the test count of the next construct:

#?DOES count

The count may be an expression as long as any variables referenced in the expression are in scope at the location fudge eventually inserts a "skip()" call.

When applied to a subsequent sub definition, fudge registers the sub name as doing that many tests when called. Note, however, that any skipping is done at the point of the call, not within the subroutine, so the count may not refer to any parameter of the sub.

When you run the fudge preprocessor, if it decides the test needs fudging, it returns the new fudged filename; otherwise it returns the original filename. (Generally you don't run fudge directly, but your test harness runs the fudgeall program for you; see below.) If there is already a fudged program in the directory that is newer than the unfudged version, fudge just returns the fudged version without regenerating it. If the fudged version is older, it removes it and then decides anew whether to regenerate it based on the internal fudge comments.

The fudgeall program may be called to process all the needed fudging for a particular implementation:

$ fudgeall rakudo */*.t */*/*.t

Program fudgeall will use the fudge program to translate any fudged files to a new file where the extension is not *.t but instead is *.rakudo to indicate the implementation dependency. It also returns the fudged list of filenames to run, where unfudged tests are just passed through unchanged as *.t. Each test comes through as either fudged or not, but never both. The test harness then runs the selected test files as it normally would (it shouldn't care whether they are named *.t or *.rakudo).

In cases where the current working directory makes a difference, the tests assume that the working directory is the root of the test suite, so that the relative path to itself is t/spec/S\d\d-$section/$filename.

To fudge and run prove on a specific file:

./fudgeandrun S05-metasyntax/angle-brackets.t

fudgeandrun does not assume any particular implementation but guesses by running perl6 to look at special variables like $*PERL. See fudgeandrun usage to specify a different implementation and other options.

Test Utilities

This repository contains Test::Util module with helper routines you can use when writing tests. See POD documentation included at the end of the module's source code. To include the module, in your test file, you need to add use lib line to your test file.

use lib $?FILE.IO.parent(2).add: 'packages/Test-Helpers';
use Test::Util;
use Test;

Depending on the location of your test file, the number inside .parent(2) may need to be adjusted to go up the correct number of times from the test files's location to the root of the repository.


The APPENDICES directory contains advisory tests implentations may optionally choose to follow. See the README included in that directory for more information.

APPENDICES are not included in released versions of the specification.

Environmental Variables


Some tests rely on a process to complete in a certain amount of time. If you're running on a slowish computer, try setting ROAST_TIMING_SCALE to a larger value that will be used as a multiplier for the time to wait. We don't wait for too long a time by default so as to make the roast run faster. Defaults to 1.