Fix accessible name calculation bug related to nested <label>s

[rcj-siteimprove]

A variable was incorrectly being shadowed causing the state to be set incorrectly in some cases. This caused some kind of explosion in the recursion which, if there were enough <label>s inside the outer label (more than 5 I think), would lead to the maximum number of stack frames being exceeded.

In addition, if the number of inner labels was small enough, it would not crash, but the accessible name of the first <input> would be incorrect. This PR fixes that. The names of <input>s inside the inner <label>s are still computed differently than what Chrome computes. It's not completely clear yet, if Chrome is actually implementing the spec and if not, if we should follow chrome or the spec.

Example

<label>
  <input type="checkbox" name="Foo" value="Yes" />Foo
  <br />
  <label><input type="checkbox" name="Bar" value="Yes" />Bar</label>
</label>

In this example the first <input> was getting the computed name of "Foo Foo BarBar" where Chrome would get "Foo Bar". With this PR we are aligned with Chrome for that element.

I also updated some function descriptions with some examples to make it a little clearer what exactly referrer and referred means for <label> and <input>s.

To do

• Update failing test.
• Add test corresponding to above example.
• Investigate what the name of inner most <input> should be.

[changeset-bot]

🦋 Changeset detected

Latest commit: 0bfbf86

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 77 packages

Name	Type
@siteimprove/alfa-aria	Patch
@siteimprove/alfa-act	Patch
@siteimprove/alfa-affine	Patch
@siteimprove/alfa-applicative	Patch
@siteimprove/alfa-array	Patch
@siteimprove/alfa-bits	Patch
@siteimprove/alfa-branched	Patch
@siteimprove/alfa-cache	Patch
@siteimprove/alfa-callback	Patch
@siteimprove/alfa-cascade	Patch
@siteimprove/alfa-clone	Patch
@siteimprove/alfa-collection	Patch
@siteimprove/alfa-comparable	Patch
@siteimprove/alfa-compatibility	Patch
@siteimprove/alfa-continuation	Patch
@siteimprove/alfa-css-feature	Patch
@siteimprove/alfa-css	Patch
@siteimprove/alfa-device	Patch
@siteimprove/alfa-dom	Patch
@siteimprove/alfa-earl	Patch
@siteimprove/alfa-either	Patch
@siteimprove/alfa-emitter	Patch
@siteimprove/alfa-encoding	Patch
@siteimprove/alfa-equatable	Patch
@siteimprove/alfa-flags	Patch
@siteimprove/alfa-fnv	Patch
@siteimprove/alfa-foldable	Patch
@siteimprove/alfa-functor	Patch
@siteimprove/alfa-future	Patch
@siteimprove/alfa-generator	Patch
@siteimprove/alfa-graph	Patch
@siteimprove/alfa-hash	Patch
@siteimprove/alfa-http	Patch
@siteimprove/alfa-iana	Patch
@siteimprove/alfa-iterable	Patch
@siteimprove/alfa-json-ld	Patch
@siteimprove/alfa-json	Patch
@siteimprove/alfa-lazy	Patch
@siteimprove/alfa-list	Patch
@siteimprove/alfa-map	Patch
@siteimprove/alfa-mapper	Patch
@siteimprove/alfa-math	Patch
@siteimprove/alfa-monad	Patch
@siteimprove/alfa-network	Patch
@siteimprove/alfa-option	Patch
@siteimprove/alfa-parser	Patch
@siteimprove/alfa-performance	Patch
@siteimprove/alfa-predicate	Patch
@siteimprove/alfa-promise	Patch
@siteimprove/alfa-record	Patch
@siteimprove/alfa-rectangle	Patch
@siteimprove/alfa-reducer	Patch
@siteimprove/alfa-refinement	Patch
@siteimprove/alfa-result	Patch
@siteimprove/alfa-rules	Patch
@siteimprove/alfa-sarif	Patch
@siteimprove/alfa-selective	Patch
@siteimprove/alfa-selector	Patch
@siteimprove/alfa-sequence	Patch
@siteimprove/alfa-set	Patch
@siteimprove/alfa-slice	Patch
@siteimprove/alfa-string	Patch
@siteimprove/alfa-style	Patch
@siteimprove/alfa-table	Patch
@siteimprove/alfa-test	Patch
@siteimprove/alfa-thenable	Patch
@siteimprove/alfa-thunk	Patch
@siteimprove/alfa-time	Patch
@siteimprove/alfa-toolchain	Patch
@siteimprove/alfa-trampoline	Patch
@siteimprove/alfa-tree	Patch
@siteimprove/alfa-trilean	Patch
@siteimprove/alfa-tuple	Patch
@siteimprove/alfa-url	Patch
@siteimprove/alfa-wcag	Patch
@siteimprove/alfa-web	Patch
@siteimprove/alfa-xpath	Patch

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