AutoTest: Redo running tests

Removing the event loop and the costly internal
infinite loop to reduce CPU load.
We need an event loop for on-the-fly processing
of the results, but the main event loop is good
enough for this. There is no need to add another
one.
There is also no need to put all this into an
asynchronous job as all of this happens
asynchronously anyway by using signals and slots.

Task-number: QTCREATORBUG-20439
Change-Id: I126bf0c1be3e49fd0dd477e161e4fe7a10a080c9
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/autotest/testrunner.h

@@ -31,12 +31,13 @@
 #include <QDialog>
 #include <QFutureWatcher>
 #include <QObject>
-#include <QProcess>
+#include <QQueue>
 
 QT_BEGIN_NAMESPACE
 class QComboBox;
 class QDialogButtonBox;
 class QLabel;
+class QProcess;
 QT_END_NAMESPACE
 
 namespace ProjectExplorer {
@@ -51,6 +52,8 @@ class TestRunner : public QObject
     Q_OBJECT
 
 public:
+    enum CancelReason { UserCanceled, Timeout };
+
     static TestRunner* instance();
     ~TestRunner();
 
@@ -72,6 +75,10 @@ private:
     void onFinished();
 
     int precheckTestConfigurations();
+    void scheduleNext();
+    void cancelCurrent(CancelReason reason);
+    void onProcessFinished();
+    void resetInternalPointers();
 
     void runTests();
     void debugTests();
@@ -79,8 +86,12 @@ private:
     explicit TestRunner(QObject *parent = 0);
 
     QFutureWatcher<TestResultPtr> m_futureWatcher;
-    QList<TestConfiguration *> m_selectedTests;
-    bool m_executingTests;
+    QFutureInterface<TestResultPtr> *m_fakeFutureInterface = nullptr;
+    QQueue<TestConfiguration *> m_selectedTests;
+    bool m_executingTests = false;
+    TestConfiguration *m_currentConfig = nullptr;
+    QProcess *m_currentProcess = nullptr;
+    TestOutputReader *m_currentOutputReader = nullptr;
     TestRunMode m_runMode = TestRunMode::Run;
 
     // temporarily used if building before running is necessary