[HEAD BROKEN] Consistent failure in MonthDatePluginTest

What timezone does the testbot live in? Did it just switch to DST?

Another victim: #2867520: Dropdown menu is not vertically aligned.

I think that @xjm once told me that issues like this should be considered Critical. Let's at least call this major.

I asked on Slack,

I wonder: what timezone does the testbot live in? Did it just switch to DST?

and @larowlan replied,

The TZ is Sydney, and yes just finished DST

so I think my guess is right. Changing the dates of the test nodes from 2020-10-01 and 2020-11-01 to 2020-10-05 and 2020-11-05 fixes the problem when I run the test locally. Patch attached.

In case anyone is curious about why timezones were my first guess. The name of the test is a hint. In addition, I used to be active on the Vim users' mailing list. Once or twice a year (I forget whether it was the start or end of DST or both) there would be a flurry of bug reports from Windows users.

I am crediting @mondrake because they added #3207083: [HEAD BROKEN] Drupal\Tests\views\Functional\Plugin\MonthDatePluginTest::testMonthDatePlugin started failing on DrupalCI a couple of hours before I added this issue.

More victims:

• #2571475: Outbound HTTP requests fail with KernelTestBase
• #2941208: Title formatting broken due to flawed EntityViewController->buildTitle
• #3167426: CurrentPathStack::getPath should always return a path with leading slashes
• #2496913: Don't expose entity types with string ids as a target option when creating comment types
• #3113989: Media author views filter should use the user_name plugin
• #2484991: Add the session to the request in KernelTestBase, BrowserTestBase, and drush
• #3186834: Sorting nodes by title aren't returned in correct order.
• #3204883: Move exclusion of taxonomy terms from moderation to content_moderation module
• #3149863: Olivero: Modal dialog buttons not aligned (for example, in the "Leave preview" dialog)
• #3207032: Back button, alignment bug in IE11 / Olivero
• #3191725: Ensure that tabledrag user interface is usable within Olivero
• #3013435: Translations directory not autocreated
• #2277551: Add a 'static' variant to the progress bar
• #3056258: Allow redirection to vocabulary list terms page after creating a new term
• #3171827: RouteNotFoundException: Route "jsonapi.[entity].[field_name].related" does not exist
• #2839558: Blocks do not have a "remove" contextual link
• #2715145: Remove system.authorize config

I think that is all at this point. I added comments to each with a link to this issue. Let's hope people wait until this issue is fixed before asking the testbot to try again.

Since this bug is time-sensitive, I want to get this on the record while I can reproduce the failing test. I can reproduce the problem locally, and my patch fixes it.

benji@pop-os:~/Sites/drupal$ git diff 9.2.x
diff --git a/core/modules/views/tests/src/Functional/Plugin/MonthDatePluginTest.php b/core/modules/views/tests/src/Functional/Plugin/MonthDatePluginTest.php
index 2f6712432a..fdd120390f 100644
--- a/core/modules/views/tests/src/Functional/Plugin/MonthDatePluginTest.php
+++ b/core/modules/views/tests/src/Functional/Plugin/MonthDatePluginTest.php
@@ -50,9 +50,9 @@ class MonthDatePluginTest extends ViewTestBase {
    */
   public function setUp($import_test_views = TRUE): void {
     parent::setUp($import_test_views);
-    $date1 = '2020-10-01 00:00:00';
+    $date1 = '2020-10-05 00:00:00';
     $this->node1 = $this->drupalCreateNode(['created' => strtotime($date1)]);
-    $date2 = '2020-11-01 00:00:00';
+    $date2 = '2020-11-05 00:00:00';
     $this->node2 = $this->drupalCreateNode(['created' => strtotime($date2)]);
   }
 
benji@pop-os:~/Sites/drupal$ lando phpunit core/modules/views/tests/src/Functional/Plugin/MonthDatePluginTest.php
PHPUnit 8.5.13 by Sebastian Bergmann and contributors.

Testing Drupal\Tests\views\Functional\Plugin\MonthDatePluginTest
.                                                                   1 / 1 (100%)

Time: 5.93 seconds, Memory: 6.00 MB

OK (1 test, 3 assertions)

HTML output was generated
https://drupal.lndo.site//sites/simpletest/browser_output/Drupal_Tests_views_Functional_Plugin_MonthDatePluginTest-30-46453418.html
https://drupal.lndo.site//sites/simpletest/browser_output/Drupal_Tests_views_Functional_Plugin_MonthDatePluginTest-31-46453418.html
https://drupal.lndo.site//sites/simpletest/browser_output/Drupal_Tests_views_Functional_Plugin_MonthDatePluginTest-32-46453418.html
https://drupal.lndo.site//sites/simpletest/browser_output/Drupal_Tests_views_Functional_Plugin_MonthDatePluginTest-33-46453418.html
https://drupal.lndo.site//sites/simpletest/browser_output/Drupal_Tests_views_Functional_Plugin_MonthDatePluginTest-34-46453418.html
benji@pop-os:~/Sites/drupal$ git checkout 9.2.x
Switched to branch '9.2.x'
Your branch is up to date with 'origin/9.2.x'.
benji@pop-os:~/Sites/drupal$ lando phpunit core/modules/views/tests/src/Functional/Plugin/MonthDatePluginTest.php
PHPUnit 8.5.13 by Sebastian Bergmann and contributors.

Testing Drupal\Tests\views\Functional\Plugin\MonthDatePluginTest
E                                                                   1 / 1 (100%)

Time: 5.72 seconds, Memory: 6.00 MB

There was 1 error:

1) Drupal\Tests\views\Functional\Plugin\MonthDatePluginTest::testMonthDatePlugin
Behat\Mink\Exception\ResponseTextException: The text "uDt53U1i" appears in the text of this page, but it should not.

/app/vendor/behat/mink/src/WebAssert.php:785
/app/vendor/behat/mink/src/WebAssert.php:279
/app/core/tests/Drupal/Tests/WebAssert.php:896
/app/core/modules/views/tests/src/Functional/Plugin/MonthDatePluginTest.php:81
/app/vendor/phpunit/phpunit/src/Framework/TestResult.php:691

ERRORS!
Tests: 1, Assertions: 3, Errors: 1.

HTML output was generated
https://drupal.lndo.site//sites/simpletest/browser_output/Drupal_Tests_views_Functional_Plugin_MonthDatePluginTest-35-62502147.html
https://drupal.lndo.site//sites/simpletest/browser_output/Drupal_Tests_views_Functional_Plugin_MonthDatePluginTest-36-62502147.html
https://drupal.lndo.site//sites/simpletest/browser_output/Drupal_Tests_views_Functional_Plugin_MonthDatePluginTest-37-62502147.html

Another one: #3173900: Refactor Olivero's JavaScript Drupal behaviors to use once().

I do not 100% understand how today's TZ shift affects dates from a few months ago, but I do know that if you shift 2020-11-01 00:00:00 by one hour in the wrong direction, then it will show up on the page for October, which is what happens in the test. Since the patch makes the test pass, I am about 99.99% confident that this is the right explanation.

Re #18: The issue was already promoted to Critical. I accidentally set it back to Major in #13.

I am updating the issue summary: the test failure is still reproducible even though we are past the DST change. I think that means the test (before this issue was fixed) would fail whenever Sydney is on Standard Time.

It looks as though #2969107: 500 error on passing invalid month to MonthDate view argument handler was committed to the 8.9.x branch. I think that means we should backport this issue, too. I tested locally with and without the patch from #14: the test fails without the patch.

Oops, my issue summary update was not quite right.

I am not sure that we have a complete understanding of the problem here.

The patch in #4 and the one in #15 both get the test to pass. One patch moves the dates to the 5'th of the month instead of the 1'st. The other patch has the effect of moving the times from 00:00:00 to 10:00:00 or 11:00:00 (ST/DST). Either change is enough to protect the timestamps from moving to the wrong month if the TZ calculation is off by 1 hour because of DST confusion.

This test started failing when Sydney switched from DST to ST. The problem is not that our timestamps are in the wrong timezone. The problem is that somewhere the DST adjustment is off.

Is the patch in #15 really better than the one in #4? It is if you think that the right thing to do is express all times in UTC. If that were the case, then I would expect

    $this->node3 = $this->drupalCreateNode([
      'created' => \DateTime::createFromFormat($format, '2020-09-30 23:59:59', $utc)->getTimestamp(),
    ]);

to reliably have its month set to September, not October. In other words, I would expect the test to pass with the attached patch (applied to 9.2.x, where this issue is already fixed). When I test locally, it fails.

I will not ask the testbot to try the attached patch, because I want to keep the status at RTBC for 8.9.x.

If I am right that we still have work to do, then I think we can do it in a non-critical follow-up issue.

@Spokje:

Thanks for checking!

@benjifisher seems to have left his drush reference in the patch

I was not able to sleep last night. When I get out of bed because a question is nagging me and I just have to test it, I am more likely to make mistakes like that.

@catch: Thanks for creating the follow-up issue.

I am crediting @jhodgdon for reviewing the patch in #4.