Convert assertions involving use of xpath on input tags to WebAssert

When I do a code base search for $this->xpath('//input[, I still find instances that are not with checkboxes.

I think the remaining ones should stay.

Could you explain why?

Back to needs work for the unresolved threads.

Could you take a look at the class Drupal\Tests\system\Functional\Form\ElementsTableSelectTest on the lines 41 and 58. Should we also do these in this issue? I agree with you on all the other ones that we should not change them. Found the answer myself. We are not doing the checkboxes in this issue.

All code change look good to me.
All instances that should be changed are changed.
A number cannot be changed, because the resulting array is used in some way like in a foreach loop.
For me it is RTBC.

It looks like we are losing the check that only a single form_build_id exists. This was added as part of #2242749: Port Form API security fix SA-CORE-2014-002 to Drupal 8 which is a security issue. This should be removed.

If the change to not count the form_build_id hidden fields is valid then we need to document why in the issue summary.

All the points of @alexpott have been addressed.
Back to RTBC.

ElementsTableSelectTest:

    $rows = ['row1', 'row2', 'row3'];
    foreach ($rows as $row) {
      $this->assertNotEmpty($this->xpath('//input[@type="checkbox"]', [$row]), "Checkbox for the value $row.");
    }

    $rows = ['row1', 'row2', 'row3'];
    foreach ($rows as $row) {
      $this->assertNotEmpty($this->xpath('//input[@type="radio"]', [$row], "Radio button value: $row"));
    }

We could fix these here? These seem buggy anyway, I think the second argument is used incorrectly.

FormElementMaxlengthTest and FilterBooleanWebTest also look like they could be converted to be a bit cleaner.

Good clean-up again.

Committed/pushed to 9.2.x and cherry-picked to 9.1.x, thanks!