The Official Perl 6 Test Suite

The purpose of the test suite is to validate implementations that wish to be known as a conforming Perl 6 implementation.

Introduction
Environment Variables
Contributing

Introduction

Please consider this test suite to be the bleeding edge of Perl 6 development. New tests, tests for experimental 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.

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:

#?MYSPECIALVAR [NUM] VERB ARGS
#!MYSPECIALVAR [NUM] VERB ARGS

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.

Environment Variables

ROAST_TIMING_SCALE

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.

Contributing

A person who wants to contribute a test to the project should read this Github guide to issues and pull requests (PRs) which describes in great detail the work flow for forks and submitting PRs to a project.

Follow the same general steps for project github.com/perl6/roast:

fork project roast
clone your fork of roast to a local directory
set the origin and upstream remotes
checkout a branch to work on your issue or proposal
- see below for details
when through, ensure all desired commits are finished
push the issue branch to your origin (your fork of roast on github)
go to your github account for project roast and submit the PR

Working the issue

Normal tests

New tests for existing features are usually accomplished by adding the test(s) to an existing test file. Then that file's plan count is updated. The new test(s) are tested locally by executing

$ perl6 <test file(s)>

When all is well, the commits are finalized, the branch is pushed to the user's fork on Github, and there the PR is initiated.

If a new test file has been created, one additional step has to be taken: the new test file has to be added to github.com/rakudo/rakudo/t/spectest.data and a PR for project github.com/rakudo/rakudo can be submitted for that. However, it is easier just to ask for help adding the new test file on IRC channel #perl6.

Fudged tests

Let's say you want to propose a new feature, method printf for IO::Handle, for rakudo and, being a believer in test-driven development, are submittng some test for something that can't yet be tested. Thus we will need to create the test but we will fudge it so it will be ignored.

We create a new test file named appropriately, say, S16-io/printf.t , the contents of which are:

use v6;
use Test;
plan 1;

my $f = './.printf-tmpfil';
my $fh = open $f, :w;
$fh.printf("Hi\n");
$fh.close;
my $res = slurp $f;
is $res, "Hi\n", "printf() works with zero args";
unlink $f;

We know the test doesn't work yet:

$ perl6 S16-io/printf.t
1..1
No such method 'printf' for invocant of type 'IO::Handle'
  in block <unit> at ./S16-io/printf.t line 9

# Looks like you planned 1 test, but ran 0

so we add the fudge to it to get the new contents:

use v6;
use Test;
plan 1;

#?rakudo skip 'RT #999999 not yet implemented'
{
    my $f = './.printf-tmpfil';
    my $fh = open $f, :w;
    $fh.printf("Hi\n");
    $fh.close;
    my $res = slurp $f;
    is $res, "Hi\n", "printf() works with zero args";
    unlink $f;
}

Notice we put the test in a block. All tests in that block are affected by the fudge line preceding it.

We want to test the fudged file before we submit the PR so we have to manually create the fudged test file:

$ fudge rakudo S16-io/printf.t
S16-io/printf.rakudo

which, as we see by the return from the command, produces file S16-io/printf.rakudo whose contents are

use v6;
use Test;
plan 1;

#?rakudo skip 'RT #999999 not yet implemented'
skip('RT #999999 not yet implemented', 1);# {
#     my $f = './.printf-tmpfil';
#     my $fh = open $f, :w;
#     $fh.printf("Hi\n");
#     $fh.close;
#     my $res = slurp $f;
#     is $res, "Hi\n", "printf() works with zero args";
#     unlink $f;
# }

say "# FUDGED!";
exit(1);

We can then test it:

$ perl6 S16-io/printf.rakudo
1..1
ok 1 - \# SKIP RT \#999999 not yet implemented
# FUDGED!

Success! Now we can commit the new test file, but NOT the generated fudge test file—that will be generated automatically by the test harness during the regular testing on the servers. As described earlier, the new test file will have to be added to the spectest.data file, either via a PR or a request to someone on IRC to add it.

samcv/roast