1Test2::Transition(3) User Contributed Perl Documentation Test2::Transition(3)
2
6 Test2::Transition - Transition notes when upgrading to Test2
7
9 This is where gotchas and breakages related to the Test2 upgrade are
10 documented. The upgrade causes Test::Builder to defer to Test2 under
11 the hood. This transition is mostly transparent, but there are a few
12 cases that can trip you up.
13
15 This is the list of scenarios that break with the new internals.
16 Test::Builder1.5/2 conditionals
18 The Problem
19 a few years back there were two attempts to upgrade/replace
21 Test::Builder. Confusingly these were called Test::Builder2 and
22 Test::Builder1.5, in that order. Many people put conditionals in their
23 code to check the Test::Builder version number and adapt their code
24 accordingly.
25 The Test::Builder2/1.5 projects both died out. Now the conditional code
27 people added has become a mine field. A vast majority of modules broken
28 by Test2 fall into this category.
29 The Fix
31 The fix is to remove all Test::Builder1.5/2 related code. Either use
33 the legacy Test::Builder API, or use Test2 directly.
34 Replacing the Test::Builder singleton
36 The Problem
37 Some test modules would replace the Test::Builder singleton instance
39 with their own instance or subclass. This was usually done to intercept
40 or modify results as they happened.
41 The Test::Builder singleton is now a simple compatibility wrapper
43 around Test2. The Test::Builder singleton is no longer the central
44 place for results. Many results bypass the Test::Builder singleton
45 completely, which breaks and behavior intended when replacing the
46 singleton.
47 The Fix
49 If you simply want to intercept all results instead of letting them go
51 to TAP, you should look at the Test2::API docs and read about pushing a
52 new hub onto the hub stack. Replacing the hub temporarily is now the
53 correct way to intercept results.
54 If your goal is purely monitoring of events use the
56 "Test2::Hub->listen()" method exported by Test::More to watch events as
57 they are fired. If you wish to modify results before they go to TAP
58 look at the "Test2::Hub->filter()" method.
59 Directly Accessing Hash Elements
61 The Problem
62 Some modules look directly at hash keys on the Test::Builder singleton.
64 The problem here is that the Test::Builder singleton no longer holds
65 anything important.
66 The Fix
68 The fix is to use the API specified in Test2::API to look at or modify
70 state as needed.
71 Subtest indentation
73 The Problem
74 An early change, in fact the change that made Test2 an idea, was a
76 change to the indentation of the subtest note. IT was decided it would
77 be more readable to outdent the subtest note instead of having it
78 inline with the subtest:
79 # subtest foo
81 ok 1 - blah
82 1..1
83 ok 1 - subtest foo
84 The old style indented the note:
86 # subtest foo
88 ok 1 - blah
89 1..1
90 ok 1 - subtest foo
91 This breaks tests that do string comparison of TAP output.
93 The Fix
95 my $indent = $INC{'Test2/API.pm'} ? '' : ' ';
97 is(
99 $subtest_output,
100 "${indent}# subtest foo",
101 "Got subtest note"
102 );
103 Check if $INC{'Test2/API.pm'} is set, if it is then no indentation
105 should be expected. If it is not set than the old Test::Builder is in
106 use, indentation should be expected.
107
109 This is a list of cpan modules that have been known to have been broken
110 by the upgrade at one point.
111 WORKS BUT TESTS WILL FAIL
113 These modules still function correctly, but their test suites will not
114 pass. If you already have these modules installed then you can continue
115 to use them. If you are trying to install them after upgrading
116 Test::Builder you will need to force installation, or bypass the broken
117 tests.
118 Test::DBIx::Class::Schema
120 This module has a test that appears to work around a Test::Builder
121 bug. The bug appears to have been fixed by Test2, which means the
122 workaround causes a failure. This can be easily updated, but nobody
123 has done so yet.
124 Known broken in versions: 1.0.9 and older
126 Test::Kit
128 This actually works fine, but will not install because
129 Test::Aggregate is in the dependency chain.
130 See the Test::Aggregate info below for additional information.
132 Device::Chip
134 Tests break due to subtest indentation.
135 Known broken in version 0.07. Apparently works fine in 0.06 though.
137 Patch has been submitted to fix the issue.
138 UPGRADE SUGGESTED
140 These are modules that did not break, but had broken test suites that
141 have since been fixed.
142 Test::Exception
144 Old versions work fine, but have a minor test name behavior that
145 breaks with Test2. Old versions will no longer install because of
146 this. The latest version on CPAN will install just fine. Upgrading
147 is not required, but is recommended.
148 Fixed in version: 0.43
150 Data::Peek
152 Some tests depended on $! and $? being modified in subtle ways. A
153 patch was applied to correct things that changed.
154 The module itself works fine, there is no need to upgrade.
156 Fixed in version: 0.45
158 circular::require
160 Some tests were fragile and required base.pm to be loaded at a late
161 stage. Test2 was loading base.pm too early. The tests were updated
162 to fix this.
163 The module itself never broke, you do not need to upgrade.
165 Fixed in version: 0.12
167 Test::Module::Used
169 A test worked around a now-fixed planning bug. There is no need to
170 upgrade if you have an old version installed. New versions install
171 fine if you want them.
172 Fixed in version: 0.2.5
174 Test::Moose::More
176 Some tests were fragile, but have been fixed. The actual breakage
177 was from the subtest comment indentation change.
178 No need to upgrade, old versions work fine. Only new versions will
180 install.
181 Fixed in version: 0.025
183 Test::FITesque
185 This was broken by a bugfix to how planning is done. The test was
186 updated after the bugfix.
187 Fixed in version: 0.04
189 autouse
191 A test broke because it depended on Scalar::Util not being loaded.
192 Test2 loads Scalar::Util. The test was updated to load Test2 after
193 checking Scalar::Util's load status.
194 There is no need to upgrade if you already have it installed.
196 Fixed in version: 1.11
198 NEED TO UPGRADE
200 Test::SharedFork
201 Old versions need to directly access Test::Builder singleton hash
202 elements. The latest version on CPAN will still do this on old
203 Test::Builder, but will defer to Test2::IPC on Test2.
204 Fixed in version: 0.35
206 Test::Builder::Clutch
208 This works by doing overriding methods on the singleton, and
209 directly accessing hash values on the singleton. A new version has
210 been released that uses the Test2 API to accomplish the same result
211 in a saner way.
212 Fixed in version: 0.07
214 Test::Dist::VersionSync
216 This had Test::Builder2 conditionals. This was fixed by removing
217 the conditionals.
218 Fixed in version: 1.1.4
220 Test::Modern
222 This relied on "Test::Builder->_try()" which was a private method,
223 documented as something nobody should use. This was fixed by using
224 a different tool.
225 Fixed in version: 0.012
227 Test::UseAllModules
229 Version 0.14 relied on "Test::Builder->history" which was available
230 in Test::Builder 1.5. Versions 0.12 and 0.13 relied on other
231 Test::Builder internals.
232 Fixed in version: 0.15
234 Test::More::Prefix
236 Worked by applying a role that wrapped
237 "Test::Builder->_print_comment". Fixed by adding an event filter
238 that modifies the message instead when running under Test2.
239 Fixed in version: 0.007
241 STILL BROKEN
243 Test::Aggregate
244 This distribution directly accesses the hash keys in the
245 Test::Builder singleton. It also approaches the problem from the
246 wrong angle, please consider using Test2::Harness or App::ForkProve
247 which both solve the same problem at the harness level.
248 Still broken as of version: 0.373
250 Test::Wrapper
252 This module directly uses hash keys in the Test::Builder singleton.
253 This module is also obsolete thanks to the benefits of Test2. Use
254 "intercept()" from Test2::API to achieve a similar result.
255 Still broken as of version: 0.3.0
257 Test::ParallelSubtest
259 This module overrides "Test::Builder::subtest()" and
260 "Test::Builder::done_testing()". It also directly accesses hash
261 elements of the singleton. It has not yet been fixed.
262 Alternatives: Test2::AsyncSubtest and Test2::Workflow (not stable).
264 Still broken as of version: 0.05
266 Test::Pretty
268 See https://github.com/tokuhirom/Test-Pretty/issues/25
269 The author admits the module is crazy, and he is awaiting a stable
271 release of something new (Test2) to completely rewrite it in a sane
272 way.
273 Still broken as of version: 0.32
275 Net::BitTorrent
277 The tests for this module directly access Test::Builder hash keys.
278 Most, if not all of these hash keys have public API methods that
279 could be used instead to avoid the problem.
280 Still broken in version: 0.052
282 Test::Group
284 It monkeypatches Test::Builder, and calls it "black magic" in the
285 code.
286 Still broken as of version: 0.20
288 Test::Flatten
290 This modifies the Test::Builder internals in many ways. A better
291 was to accomplish the goal of this module is to write your own
292 subtest function.
293 Still broken as of version: 0.11
295 Log::Dispatch::Config::TestLog
297 Modifies Test::Builder internals.
298 Still broken as of version: 0.02
300 Test::Able
302 Modifies Test::Builder internals.
303 Still broken as of version: 0.11
305
307 LEGACY
308 use Test::Builder;
309 # A majority of tools out there do this:
311 # my $TB = Test::Builder->new;
312 # This works, but has always been wrong, forcing Test::Builder to implement
313 # subtests as a horrific hack. It also causes problems for tools that try
314 # to replace the singleton (also discouraged).
315 sub my_ok($;$) {
317 my ($bool, $name) = @_;
318 my $TB = Test::Builder->new;
319 $TB->ok($bool, $name);
320 }
321 sub my_diag($) {
323 my ($msg) = @_;
324 my $TB = Test::Builder->new;
325 $TB->diag($msg);
326 }
327 TEST2
329 use Test2::API qw/context/;
330 sub my_ok($;$) {
332 my ($bool, $name) = @_;
333 my $ctx = context();
334 $ctx->ok($bool, $name);
335 $ctx->release;
336 }
337 sub my_diag($) {
339 my ($msg) = @_;
340 my $ctx = context();
341 $ctx->diag($msg);
342 $ctx->release;
343 }
344 The context object has API compatible implementations of the following
346 methods:
347 ok($bool, $name)
349 diag(@messages)
350 note(@messages)
351 subtest($name, $code)
352 If you are looking for helpers with "is", "like", and others, see
354 Test2::Suite.
355
357 LEGACY
358 use Test::More;
359 sub exclusive_ok {
361 my ($bool1, $bool2, $name) = @_;
362 # Ensure errors are reported 1 level higher
364 local $Test::Builder::Level = $Test::Builder::Level + 1;
365 $ok = $bool1 || $bool2;
367 $ok &&= !($bool1 && $bool2);
368 ok($ok, $name);
369 return $bool;
371 }
372 Every single tool in the chain from this, to "ok", to anything "ok"
374 calls needs to increment the $Level variable. When an error occurs
375 Test::Builder will do a trace to the stack frame determined by $Level,
376 and report that file+line as the one where the error occurred. If you
377 or any other tool you use forgets to set $Level then errors will be
378 reported to the wrong place.
379 TEST2
381 use Test::More;
382 sub exclusive_ok {
384 my ($bool1, $bool2, $name) = @_;
385 # Grab and store the context, even if you do not need to use it
387 # directly.
388 my $ctx = context();
389 $ok = $bool1 || $bool2;
391 $ok &&= !($bool1 && $bool2);
392 ok($ok, $name);
393 $ctx->release;
395 return $bool;
396 }
397 Instead of using $Level to perform a backtrace, Test2 uses a context
399 object. In this sample you create a context object and store it. This
400 locks the context (errors report 1 level up from here) for all wrapped
401 tools to find. You do not need to use the context object, but you do
402 need to store it in a variable. Once the sub ends the $ctx variable is
403 destroyed which lets future tools find their own.
404
406 LEGACY
407 # Set the mode BEFORE anything loads Test::Builder
408 use open ':std', ':encoding(utf8)';
409 use Test::More;
410 Or
412 # Modify the filehandles
414 my $builder = Test::More->builder;
415 binmode $builder->output, ":encoding(utf8)";
416 binmode $builder->failure_output, ":encoding(utf8)";
417 binmode $builder->todo_output, ":encoding(utf8)";
418 TEST2
420 use Test2::API qw/test2_stack/;
421 test2_stack->top->format->encoding('utf8');
423 Though a much better way is to use the Test2::Plugin::UTF8 plugin,
425 which is part of Test2::Suite.
426
428 The following people have all contributed to this document in some way,
429 even if only for review.
430 Chad Granum (EXODIST) <exodist@cpan.org>
432
434 The source code repository for Test2 can be found at
435 http://github.com/Test-More/test-more/.
436
438 Chad Granum <exodist@cpan.org>
439
441 Copyright 2019 Chad Granum <exodist@cpan.org>.
442 This program is free software; you can redistribute it and/or modify it
444 under the same terms as Perl itself.
445 See http://www.perl.com/perl/misc/Artistic.html
447perl v5.28.1 2019-02-06 Test2::Transition(3)