This tests that aria trees and tree items are converted into AXOutlines and AXRows, with all the right attributes.

PASS: tree.role === 'AXRole: AXOutline'
PASS: canSetRows === true
PASS: tree.childrenCount === 8
PASS: treeitem1.role === 'AXRole: AXRow'
PASS: treeitem1.subrole === 'AXSubrole: AXOutlineRow'
PASS: treeitem1.isExpanded === true
PASS: treeitem1.hierarchicalLevel === 0
PASS: canSetDisclosing === true
PASS: treeitem2.role === 'AXRole: AXRow'
PASS: treeitem2.subrole === 'AXSubrole: AXOutlineRow'
PASS: treeitem2.isExpanded === false
PASS: treeitem2.hierarchicalLevel === 1
PASS: treeitem2.disclosedByRow().isEqual(treeitem1) === true
PASS: canSetDisclosing === false
PASS: treeitem3.stringValue === 'AXValue: Birds'
PASS: canSetDisclosing === false
PASS: treeitem3.role === 'AXRole: AXRow'
PASS: treeitem3.subrole === 'AXSubrole: AXOutlineRow'
PASS: treeitem3.isExpanded === true
PASS: treeitem3.isSelected === false
PASS: treeitem3.isSelected === true
PASS: selectedRow.isEqual(treeitem3) === true
PASS: treeitem4.hierarchicalLevel === 0
PASS: treeitem5.hierarchicalLevel === 1
PASS: treeitem6.hierarchicalLevel === 1

Updating aria-level of #treeitem2 to 3.
PASS: treeitem2.hierarchicalLevel === 2

PASS successfullyParsed is true

TEST COMPLETE
Animals
Birds
Cats
Siamese
Tabby
Vegetables
Carrots
Broccoli