Improve robustness of tst_lowenergycontroller test

The test checks the value of various descriptors and characteristics
of the TI Sensortag. One of those values are
ClientCharacteristicConfiguration descriptors. This type of descriptor
is consistent across multiple session for the same connecting central
device. Therefore it may change and would create frequent test failures.
Even worse, the unit test itself toggles the CCC value and assuming that
a test may fail, the CC may remain with an uncertain value.

This change makes the CCC value test more generic as it checks that
the found value is within the acceptable range w/o expecting a defined
value.

Change-Id: I004a1037ee9e602807e4df5511c7d2205c92e5fe
Reviewed-by: Oliver Wolff <oliver.wolff@qt.io>
Reviewed-by: Timur Pocheptsov <timur.pocheptsov@qt.io>

1 files changed, 36 insertions, 15 deletions

diff --git a/tests/auto/qlowenergycontroller/tst_qlowenergycontroller.cpp b/tests/auto/qlowenergycontroller/tst_qlowenergycontroller.cpp
index 1d1997e0..53c2f754 100644
--- a/tests/auto/qlowenergycontroller/tst_qlowenergycontroller.cpp
+++ b/tests/auto/qlowenergycontroller/tst_qlowenergycontroller.cpp
@@ -92,6 +92,7 @@ private slots:
     void tst_errorCases();
 private:
     void verifyServiceProperties(const QLowEnergyService *info);
+    bool verifyClientCharacteristicValue(const QByteArray& value);
 
     QBluetoothDeviceDiscoveryAgent *devAgent;
     QBluetoothAddress remoteDevice;
@@ -708,7 +709,7 @@ void tst_QLowEnergyController::verifyServiceProperties(
                 QBluetoothUuid(QBluetoothUuid::ClientCharacteristicConfiguration));
         QCOMPARE(chars[0].descriptors().at(0).type(),
                 QBluetoothUuid::ClientCharacteristicConfiguration);
-        QCOMPARE(chars[0].descriptors().at(0).value(), QByteArray::fromHex("0000"));
+        QVERIFY(verifyClientCharacteristicValue(chars[0].descriptors().at(0).value()));
         QVERIFY(info->contains(chars[0].descriptors().at(0)));
     } else if (info->serviceUuid() ==
                 QBluetoothUuid(QString("0000180a-0000-1000-8000-00805f9b34fb"))) {
@@ -841,7 +842,7 @@ void tst_QLowEnergyController::verifyServiceProperties(
                 QBluetoothUuid(QBluetoothUuid::ClientCharacteristicConfiguration));
         QCOMPARE(chars[0].descriptors().at(0).type(),
                 QBluetoothUuid::ClientCharacteristicConfiguration);
-        QCOMPARE(chars[0].descriptors().at(0).value(), QByteArray::fromHex("0000"));
+        QVERIFY(verifyClientCharacteristicValue(chars[0].descriptors().at(0).value()));
         QVERIFY(info->contains(chars[0].descriptors().at(0)));
 
         QCOMPARE(chars[0].descriptors().at(1).isValid(), true);
@@ -928,7 +929,7 @@ void tst_QLowEnergyController::verifyServiceProperties(
                 QBluetoothUuid(QBluetoothUuid::ClientCharacteristicConfiguration));
         QCOMPARE(chars[0].descriptors().at(0).type(),
                 QBluetoothUuid::ClientCharacteristicConfiguration);
-        QCOMPARE(chars[0].descriptors().at(0).value(), QByteArray::fromHex("0000"));
+        QVERIFY(verifyClientCharacteristicValue(chars[0].descriptors().at(0).value()));
         QVERIFY(info->contains(chars[0].descriptors().at(0)));
 
         QCOMPARE(chars[0].descriptors().at(1).isValid(), true);
@@ -968,7 +969,7 @@ void tst_QLowEnergyController::verifyServiceProperties(
                  QBluetoothUuid(QBluetoothUuid::ClientCharacteristicConfiguration));
         QCOMPARE(chars[0].descriptors().at(0).type(),
                  QBluetoothUuid::ClientCharacteristicConfiguration);
-        QCOMPARE(chars[0].descriptors().at(0).value(), QByteArray::fromHex("0000"));
+        QVERIFY(verifyClientCharacteristicValue(chars[0].descriptors().at(0).value()));
         QVERIFY(info->contains(chars[0].descriptors().at(0)));
 
         QCOMPARE(chars[0].descriptors().at(1).isValid(), true);
@@ -1055,7 +1056,7 @@ void tst_QLowEnergyController::verifyServiceProperties(
                 QBluetoothUuid(QBluetoothUuid::ClientCharacteristicConfiguration));
         QCOMPARE(chars[0].descriptors().at(0).type(),
                 QBluetoothUuid::ClientCharacteristicConfiguration);
-        QCOMPARE(chars[0].descriptors().at(0).value(), QByteArray::fromHex("0000"));
+        QVERIFY(verifyClientCharacteristicValue(chars[0].descriptors().at(0).value()));
         QVERIFY(info->contains(chars[0].descriptors().at(0)));
 
         QCOMPARE(chars[0].descriptors().at(1).isValid(), true);
@@ -1143,7 +1144,7 @@ void tst_QLowEnergyController::verifyServiceProperties(
                  QBluetoothUuid(QBluetoothUuid::ClientCharacteristicConfiguration));
         QCOMPARE(chars[0].descriptors().at(0).type(),
                  QBluetoothUuid::ClientCharacteristicConfiguration);
-        QCOMPARE(chars[0].descriptors().at(0).value(), QByteArray::fromHex("0000"));
+        QVERIFY(verifyClientCharacteristicValue(chars[0].descriptors().at(0).value()));
         QVERIFY(info->contains(chars[0].descriptors().at(0)));
 
         QCOMPARE(chars[0].descriptors().at(1).isValid(), true);
@@ -1230,7 +1231,7 @@ void tst_QLowEnergyController::verifyServiceProperties(
                 QBluetoothUuid(QBluetoothUuid::ClientCharacteristicConfiguration));
         QCOMPARE(chars[0].descriptors().at(0).type(),
                 QBluetoothUuid::ClientCharacteristicConfiguration);
-        QCOMPARE(chars[0].descriptors().at(0).value(), QByteArray::fromHex("0000"));
+        QVERIFY(verifyClientCharacteristicValue(chars[0].descriptors().at(0).value()));
         QVERIFY(info->contains(chars[0].descriptors().at(0)));
 
         QCOMPARE(chars[0].descriptors().at(1).isValid(), true);
@@ -1299,7 +1300,7 @@ void tst_QLowEnergyController::verifyServiceProperties(
                     QBluetoothUuid(QBluetoothUuid::ClientCharacteristicConfiguration));
             QCOMPARE(calibration.descriptors().at(0).type(),
                     QBluetoothUuid::ClientCharacteristicConfiguration);
-            QCOMPARE(calibration.descriptors().at(0).value(), QByteArray::fromHex("0000"));
+            QVERIFY(verifyClientCharacteristicValue(calibration.descriptors().at(0).value()));
             QVERIFY(info->contains(calibration.descriptors().at(0)));
 
             QCOMPARE(calibration.descriptors().at(1).isValid(), true);
@@ -1365,7 +1366,7 @@ void tst_QLowEnergyController::verifyServiceProperties(
                 QBluetoothUuid(QBluetoothUuid::ClientCharacteristicConfiguration));
         QCOMPARE(chars[0].descriptors().at(0).type(),
                 QBluetoothUuid::ClientCharacteristicConfiguration);
-        QCOMPARE(chars[0].descriptors().at(0).value(), QByteArray::fromHex("0000"));
+        QVERIFY(verifyClientCharacteristicValue(chars[0].descriptors().at(0).value()));
         QVERIFY(info->contains(chars[0].descriptors().at(0)));
 
         QCOMPARE(chars[0].descriptors().at(1).isValid(), true);
@@ -1503,8 +1504,7 @@ void tst_QLowEnergyController::verifyServiceProperties(
                 QBluetoothUuid(QBluetoothUuid::ClientCharacteristicConfiguration));
         QCOMPARE(chars[0].descriptors().at(0).type(),
                 QBluetoothUuid::ClientCharacteristicConfiguration);
-        // value different in other revisions and test may fail
-        QCOMPARE(chars[0].descriptors().at(0).value(), QByteArray::fromHex("0100"));
+        QVERIFY(verifyClientCharacteristicValue(chars[0].descriptors().at(0).value()));
         QVERIFY(info->contains(chars[0].descriptors().at(0)));
 
         QCOMPARE(chars[0].descriptors().at(1).isValid(), true);
@@ -1582,8 +1582,7 @@ void tst_QLowEnergyController::verifyServiceProperties(
                 QBluetoothUuid(QBluetoothUuid::ClientCharacteristicConfiguration));
         QCOMPARE(chars[0].descriptors().at(0).type(),
                 QBluetoothUuid::ClientCharacteristicConfiguration);
-        // value different in other revisions and test may fail
-        QCOMPARE(chars[0].descriptors().at(0).value(), QByteArray::fromHex("0100"));
+        QVERIFY(verifyClientCharacteristicValue(chars[0].descriptors().at(0).value()));
         QVERIFY(info->contains(chars[0].descriptors().at(0)));
 
         QCOMPARE(chars[0].descriptors().at(1).isValid(), true);
@@ -1617,8 +1616,7 @@ void tst_QLowEnergyController::verifyServiceProperties(
                 QBluetoothUuid(QBluetoothUuid::ClientCharacteristicConfiguration));
         QCOMPARE(chars[1].descriptors().at(0).type(),
                 QBluetoothUuid::ClientCharacteristicConfiguration);
-        // value different in other revisions and test may fail
-        QCOMPARE(chars[1].descriptors().at(0).value(), QByteArray::fromHex("0100"));
+        QVERIFY(verifyClientCharacteristicValue(chars[0].descriptors().at(0).value()));
         QVERIFY(info->contains(chars[1].descriptors().at(0)));
 
         QCOMPARE(chars[1].descriptors().at(1).isValid(), true);
@@ -1636,6 +1634,29 @@ void tst_QLowEnergyController::verifyServiceProperties(
     }
 }
 
+/*
+ * CCC descriptors can have one of three distinct values:
+ *      0000 - notifications and indications are off
+ *      0100 - notifications enabled
+ *      0200 - indications enabled
+ *
+ * The exact value is managed by the BTLE peripheral for each central
+ * that connects. The value of this field is session based and may be retained
+ * during multiple connections.
+ *
+ * This function returns \c true if the CCC value has a valid range.
+ * */
+bool tst_QLowEnergyController::verifyClientCharacteristicValue(const QByteArray &value)
+{
+    if (value == QByteArray::fromHex("0000")
+            || value == QByteArray::fromHex("0100")
+            || value == QByteArray::fromHex("0200") )
+        return true;
+
+    qWarning() << "Found incorrect CC value" << value.toHex();
+    return false;
+}
+
 void tst_QLowEnergyController::tst_defaultBehavior()
 {
     QList<QBluetoothAddress> foundAddresses;