[meta] 8.x-1.x test coverage

The section of the status report provided by Scheduler is not covered by tests. A patch on #2781433: Replace deprecated usage of Drupal::url in .install status report passed when manual testing showed several faults in the code. This new test file checks some text and verifies the accuracy of the hrefs in the two links provided.

I have now written tests to cover all of the actions, conditions and events we provide for interaction with Rules. However, until #2775519: Automated testing for 3rd-party modules integrating with Rules is resolved I cannot commit them to our codebase.

I committed the three Rules Integration Test files.

I have added a small test to the Revisioning file to test the 'touch' option (alter created date to match publish_on date). Also in this patch is some tidy up:

1. Use $this->nodeStorage instead of defining $node_storage
2. Add REQUEST_TIME as second parameter to strtotime() calls so that the result is consistent throughout the test
3. Remove calls to t( ) which should not be used in automated simpletests. Use printf() instead where parameter values are needed

Adding the test for the 'touch' option in 8.x is a pre-requisite to adding it in 7.x, which I want to do as part of my testing of the Drupal Coverage Coremodule on the DCC test site.

Committed, so now I can do the same on #2112869-13: 7.x test coverage

We now have a test file for the admin settings page - added in #2831429: Date format placeholders not replaced in error message

I have divided the 'node delete' test into two functions.

The SchedulerBasicTest needs a few changes:

• Remove the direct database->update calls (which are not a good thing to do) by setting the $node->$key value then using $node->save()
• Remove the unnecessary login to adminUser and just log in to schedulerUser
• Remove the setting of body text which had been used in assertions but got left in by mistake

The SchedulerDefaultTimeTest needs a few changes:

• Remove calls to date() and use \Drupal::service('date.formatter') instead
• Add new assertions to check the error message when saving an invalid default time
• Remove separate function assertDefaultTime() and put the code into the main test function
• Replace $this->assertText with $this->assertSession()->pageTextContains
• Replace $this->assertNoText with $this->assertSession()->pageTextNotContains

The above commit splits testRulesEvents() into three separate test functions testRulesEventsNone() when no scheduler dates exist in the node, testRulesEventsPublish() for testing the publish events when the node has publish date and testRulesEventsUnpublish() for the unpublish events. This is so that if one part fails we still get good info on the other parts. Or if something major is wrong then we get three test failures.

The commit in #19 expands the tests to cover setting the Scheduler dates via Rules actions when creating a new node, not just when editing an existing node.