a11y: Test and document relations better

The documentation for the RelationFlag enum was not very clear on what
was the "first" and "second" object.
And the fact that the AT-SPI backend (which these enum values originates
from) inverses "first" and "second" makes it harder to understand what
how it all fits together.

So when (with this change) Qt documents 'QAccessible::Labelled' as
    "The returned object is labelled by the origin object"

AT-SPI documents ATSPI_RELATION_LABELLED_BY as:
    "The origin object is labelled by the returned object"
(Documentation for AT-SPI is rewritten so that it shares the same
terminology)

Notice that the two objects are exchanged, which means that even if they
use the same 'Labelled' relation, the semantic gets 'inversed'.

This is already the case today, so we cannot change it. Therefore, to be
clear, the relation mapping will remain to be like this:

Qt Relation     | Maps to AT-SPI                | Qt explanation
----------------+-------------------------------+--------------------------------------------------------------------------------
Label           | ATSPI_RELATION_LABELLED_BY    | The returned object is a Label for the origin object
Labelled        | ATSPI_RELATION_LABEL_FOR      | The returned object is Labelled by the origin object

Controller      | ATSPI_RELATION_CONTROLLED_BY  | The returned object is the Controller for the origin object
Controlled      | ATSPI_RELATION_CONTROLLER_FOR | The returned object is Controlled by the origin object

This mapping can already be seen in qAccessibleRelationToAtSpiRelation()

For the record, these future relations should then be mapped to like
this:

Qt Relation     | Maps to AT-SPI                | Qt explanation
----------------+-------------------------------+--------------------------------------------------------------------------------
Described       | ATSPI_RELATION_DESCRIPTION_FOR| The returned object is described by the origin object
DescriptionFor  | ATSPI_RELATION_DESCRIBED_BY   | The returned object provides a description for the origin object

FlowsTo         | ATSPI_RELATION_FLOWS_FROM     | The returned object has content which flows logically to the origin object
FlowsFrom       | ATSPI_RELATION_FLOWS_TO       | The returned object has content which flows logically from the origin object

Change-Id: Ib245ec95564e4886dc6dbbb68abec2b23cd0e534
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
Reviewed-by: Michael Weghorn <m.weghorn@posteo.de>

1 files changed, 82 insertions, 6 deletions

diff --git a/tests/auto/other/qaccessibility/tst_qaccessibility.cpp b/tests/auto/other/qaccessibility/tst_qaccessibility.cpp
index 662d459af6..76d50b93e3 100644
--- a/tests/auto/other/qaccessibility/tst_qaccessibility.cpp
+++ b/tests/auto/other/qaccessibility/tst_qaccessibility.cpp
@@ -222,6 +222,7 @@ private slots:
     void accessibleName();
 #if QT_CONFIG(shortcut)
     void labelTest();
+    void relationTest();
     void accelerators();
 #endif
     void bridgeTest();
@@ -3688,6 +3689,69 @@ void tst_QAccessibility::comboBoxTest()
     QTestAccessibility::clearEvents();
 }
 
+void tst_QAccessibility::relationTest()
+{
+    auto windowHolder = std::make_unique<QWidget>();
+    auto window = windowHolder.get();
+    QString text = "Hello World";
+    QLabel *label = new QLabel(text, window);
+    setFrameless(label);
+    QSpinBox *spinBox = new QSpinBox(window);
+    label->setBuddy(spinBox);
+    QProgressBar *pb = new QProgressBar(window);
+    pb->setRange(0, 99);
+    connect(spinBox, SIGNAL(valueChanged(int)), pb, SLOT(setValue(int)));
+
+    window->resize(320, 200);
+    window->show();
+
+    QVERIFY(QTest::qWaitForWindowExposed(window));
+#if defined(Q_OS_UNIX)
+    QCoreApplication::processEvents();
+#endif
+    QTest::qWait(100);
+
+    QAccessibleInterface *acc_label = QAccessible::queryAccessibleInterface(label);
+    QVERIFY(acc_label);
+    QAccessibleInterface *acc_spinBox = QAccessible::queryAccessibleInterface(spinBox);
+    QVERIFY(acc_spinBox);
+    QAccessibleInterface *acc_pb = QAccessible::queryAccessibleInterface(pb);
+    QVERIFY(acc_pb);
+
+    typedef QPair<QAccessibleInterface*, QAccessible::Relation> RelationPair;
+    {
+        const QList<RelationPair> rels = acc_label->relations(QAccessible::Labelled);
+        QCOMPARE(rels.size(), 1);
+        const RelationPair relPair = rels.first();
+
+        // spinBox is Labelled by acc_label
+        QCOMPARE(relPair.first->object(), spinBox);
+        QCOMPARE(relPair.second, QAccessible::Labelled);
+    }
+
+    {
+        // Test multiple relations (spinBox have two)
+        const QList<RelationPair> rels = acc_spinBox->relations();
+        QCOMPARE(rels.size(), 2);
+        int visitCount = 0;
+        for (const auto &relPair : rels) {
+            if (relPair.second & QAccessible::Label) {
+                // label is the Label of spinBox
+                QCOMPARE(relPair.first->object(), label);
+                ++visitCount;
+            } else if (relPair.second & QAccessible::Controlled) {
+                // progressbar is Controlled by the spinBox
+                QCOMPARE(relPair.first->object(), pb);
+                ++visitCount;
+            }
+        }
+        QCOMPARE(visitCount, rels.size());
+    }
+
+    windowHolder.reset();
+    QTestAccessibility::clearEvents();
+}
+
 #if QT_CONFIG(shortcut)
 
 void tst_QAccessibility::labelTest()
@@ -3710,6 +3774,8 @@ void tst_QAccessibility::labelTest()
 
     QAccessibleInterface *acc_label = QAccessible::queryAccessibleInterface(label);
     QVERIFY(acc_label);
+    QAccessibleInterface *acc_lineEdit = QAccessible::queryAccessibleInterface(buddy);
+    QVERIFY(acc_lineEdit);
 
     QCOMPARE(acc_label->text(QAccessible::Name), text);
     QCOMPARE(acc_label->state().editable, false);
@@ -3719,13 +3785,23 @@ void tst_QAccessibility::labelTest()
     QCOMPARE(acc_label->state().focusable, false);
     QCOMPARE(acc_label->state().readOnly, true);
 
-    QList<QPair<QAccessibleInterface *, QAccessible::Relation>> rels = acc_label->relations();
-    QCOMPARE(rels.size(), 1);
-    QAccessibleInterface *iface = rels.first().first;
-    QAccessible::Relation rel = rels.first().second;
 
-    QCOMPARE(rel, QAccessible::Labelled);
-    QCOMPARE(iface->role(), QAccessible::EditableText);
+    typedef QPair<QAccessibleInterface*, QAccessible::Relation> RelationPair;
+    {
+        const QList<RelationPair> rels = acc_label->relations(QAccessible::Labelled);
+        QCOMPARE(rels.size(), 1);
+        const RelationPair relPair = rels.first();
+        QCOMPARE(relPair.first->object(), buddy);
+        QCOMPARE(relPair.second, QAccessible::Labelled);
+    }
+
+    {
+        const QList<RelationPair> rels = acc_lineEdit->relations(QAccessible::Label);
+        QCOMPARE(rels.size(), 1);
+        const RelationPair relPair = rels.first();
+        QCOMPARE(relPair.first->object(), label);
+        QCOMPARE(relPair.second, QAccessible::Label);
+    }
 
     windowHolder.reset();
     QTestAccessibility::clearEvents();