a11y atspi: Send correct D-Bus reply for GetAttributeValue

Only return a string for the attribute value
(an empty string if the attribute is not set).

The previous implementation was based on the incorrect
signature in the XML spec for the AT-SPI Text interface from
before the AT-SPI commit that removed the extra out params [1]:

    commit 8786849ce6e9914383aa766ff9ce7e00f5b2178d
    Author: Patryk Kaczmarek <patryk.k@samsung.com>
    Date:   Mon Sep 28 14:23:15 2015 +0200

        Fixed atspi_text_ functions

          * atspi_text_get_text_attribute_value
              Fixed dbus signature in _atspi_dbus_call function
              and add missing argument for string.

          * atspi_text_get_default_attributes
              Receiving return value by reference from hash table

        https://bugzilla.gnome.org/show_bug.cgi?id=755731

[1] https://gitlab.gnome.org/GNOME/at-spi2-core/-/commit/8786849ce6e9914383aa766ff9ce7e00f5b2178d

Fixes: QTBUG-105752
Change-Id: I66d3c484ecc4b469684635723242c915e4365e6a
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>
(cherry picked from commit e6599bfa6134cfd3097c9cb8ec45801ae810f3df)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

2 files changed, 4 insertions, 12 deletions

diff --git a/src/gui/accessible/linux/atspiadaptor.cpp b/src/gui/accessible/linux/atspiadaptor.cpp
index c90732d0a9..9661e517fa 100644
--- a/src/gui/accessible/linux/atspiadaptor.cpp
+++ b/src/gui/accessible/linux/atspiadaptor.cpp
@@ -451,9 +451,6 @@ QString AtSpiAdaptor::introspect(const QString &path) const
                 "      <arg direction=\"in\" type=\"i\" name=\"offset\"/>\n"
                 "      <arg direction=\"in\" type=\"s\" name=\"attributeName\"/>\n"
                 "      <arg direction=\"out\" type=\"s\"/>\n"
-                "      <arg direction=\"out\" type=\"i\" name=\"startOffset\"/>\n"
-                "      <arg direction=\"out\" type=\"i\" name=\"endOffset\"/>\n"
-                "      <arg direction=\"out\" type=\"b\" name=\"defined\"/>\n"
                 "    </method>\n"
                 "    <method name=\"GetAttributes\">\n"
                 "      <arg direction=\"in\" type=\"i\" name=\"offset\"/>\n"
@@ -1761,7 +1758,7 @@ bool AtSpiAdaptor::textInterface(QAccessibleInterface *interface, const QString
     } else if (function == "GetAttributeValue"_L1) {
         int offset = message.arguments().at(0).toInt();
         QString attributeName = message.arguments().at(1).toString();
-        connection.send(message.createReply(getAttributeValue(interface, offset, attributeName)));
+        connection.send(message.createReply(QVariant(getAttributeValue(interface, offset, attributeName))));
     } else if (function == "GetAttributes"_L1) {
         int offset = message.arguments().at(0).toInt();
         connection.send(message.createReply(getAttributes(interface, offset, true)));
@@ -2027,9 +2024,8 @@ QVariantList AtSpiAdaptor::getAttributes(QAccessibleInterface *interface, int of
     return list;
 }
 
-QVariantList AtSpiAdaptor::getAttributeValue(QAccessibleInterface *interface, int offset, const QString &attributeName) const
+QString AtSpiAdaptor::getAttributeValue(QAccessibleInterface *interface, int offset, const QString &attributeName) const
 {
-    QString mapped;
     QString joined;
     QSpiAttributeSet map;
     int startOffset;
@@ -2044,11 +2040,7 @@ QVariantList AtSpiAdaptor::getAttributeValue(QAccessibleInterface *interface, in
         if (!attribute.isNull())
             map[attribute.name] = attribute.value;
     }
-    mapped = map[attributeName];
-    const bool defined = !mapped.isEmpty();
-    QVariantList list;
-    list << mapped << startOffset << endOffset << defined;
-    return list;
+    return map[attributeName];
 }
 
 QList<QVariant> AtSpiAdaptor::getCharacterExtents(QAccessibleInterface *interface, int offset, uint coordType) const
diff --git a/src/gui/accessible/linux/atspiadaptor_p.h b/src/gui/accessible/linux/atspiadaptor_p.h
index 3d785e4c25..aaabc8c2f1 100644
--- a/src/gui/accessible/linux/atspiadaptor_p.h
+++ b/src/gui/accessible/linux/atspiadaptor_p.h
@@ -101,7 +101,7 @@ private:
 
     // text helper functions
     QVariantList getAttributes(QAccessibleInterface *, int offset, bool includeDefaults) const;
-    QVariantList getAttributeValue(QAccessibleInterface *, int offset, const QString &attributeName) const;
+    QString getAttributeValue(QAccessibleInterface *, int offset, const QString &attributeName) const;
     QList<QVariant> getCharacterExtents(QAccessibleInterface *, int offset, uint coordType) const;
     QList<QVariant> getRangeExtents(QAccessibleInterface *, int startOffset, int endOffset, uint coordType) const;
     QAccessible::TextBoundaryType qAccessibleBoundaryType(int atspiTextBoundaryType) const;