CMake: Fix progress calculation in server-mode

Add unit test to make sure this stays fixed.

Task-number: QTCREATORBUG-18624
Change-Id: Ieeb41982418481223d9ebf8f5c6ec4b3b78bfe00
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/cmakeprojectmanager/cmakeprojectplugin.h

@@ -61,6 +61,9 @@ private slots:
 
     void testCMakeProjectImporterToolChain_data();
     void testCMakeProjectImporterToolChain();
+
+    void testServerModeReaderProgress_data();
+    void testServerModeReaderProgress();
 #endif
 
 private:

src/plugins/cmakeprojectmanager/servermodereader.cpp

@@ -406,8 +406,7 @@ void ServerModeReader::handleProgress(int min, int cur, int max, const QString &
 
     if (!m_future)
         return;
-    int progress = m_progressStepMinimum
-            + (((max - min) / (cur - min)) * (m_progressStepMaximum  - m_progressStepMinimum));
+    const int progress = calculateProgress(m_progressStepMinimum, min, cur, max, m_progressStepMaximum);
     m_future->setProgressValue(progress);
 }
 
@@ -419,6 +418,14 @@ void ServerModeReader::handleSignal(const QString &signal, const QVariantMap &da
         emit dirty();
 }
 
+int ServerModeReader::calculateProgress(const int minRange, const int min, const int cur, const int max, const int maxRange)
+{
+    if (minRange == maxRange || min == max)
+        return minRange;
+    const int clampedCur = std::min(std::max(cur, min), max);
+    return minRange + ((clampedCur - min) / (max - min)) * (maxRange - minRange);
+}
+
 void ServerModeReader::extractCodeModelData(const QVariantMap &data)
 {
     const QVariantList configs = data.value("configurations").toList();
@@ -771,3 +778,59 @@ void ServerModeReader::addHeaderNodes(ProjectNode *root, const QList<FileNode *>
 
 } // namespace Internal
 } // namespace CMakeProjectManager
+
+#if defined(WITH_TESTS)
+
+#include "cmakeprojectplugin.h"
+#include <QTest>
+
+namespace CMakeProjectManager {
+namespace Internal {
+
+void CMakeProjectPlugin::testServerModeReaderProgress_data()
+{
+    QTest::addColumn<int>("minRange");
+    QTest::addColumn<int>("min");
+    QTest::addColumn<int>("cur");
+    QTest::addColumn<int>("max");
+    QTest::addColumn<int>("maxRange");
+    QTest::addColumn<int>("expected");
+
+    QTest::newRow("empty range") << 100 << 10 << 11 << 20 << 100 << 100;
+    QTest::newRow("one range (low)") << 0 << 10 << 11 << 20 << 1 << 0;
+    QTest::newRow("one range (high)") << 20 << 10 << 19 << 20 << 20 << 20;
+    QTest::newRow("large range") << 30 << 10 << 11 << 20 << 100000 << 30;
+
+    QTest::newRow("empty progress") << -5 << 10 << 10 << 10 << 99995 << -5;
+    QTest::newRow("one progress (low)") << 42 << 10 << 10 << 11 << 100042 << 42;
+    QTest::newRow("one progress (high)") << 0 << 10 << 11 << 11 << 100000 << 100000;
+    QTest::newRow("large progress") << 0 << 10 << 10 << 11 << 100000 << 0;
+
+    QTest::newRow("cur too low") << 0 << 10 << 9 << 100 << 100000 << 0;
+    QTest::newRow("cur too high") << 0 << 10 << 101 << 100 << 100000 << 100000;
+    QTest::newRow("cur much too low") << 0 << 10 << -1000 << 100 << 100000 << 0;
+    QTest::newRow("cur much too high") << 0 << 10 << 1110000 << 100 << 100000 << 100000;
+}
+
+void CMakeProjectPlugin::testServerModeReaderProgress()
+{
+    QFETCH(int, minRange);
+    QFETCH(int, min);
+    QFETCH(int, cur);
+    QFETCH(int, max);
+    QFETCH(int, maxRange);
+    QFETCH(int, expected);
+
+    ServerModeReader reader;
+    const int r = reader.calculateProgress(minRange, min, cur, max, maxRange);
+
+    QCOMPARE(r, expected);
+
+    QVERIFY(r <= maxRange);
+    QVERIFY(r >= minRange);
+}
+
+} // namespace Internal
+} // namespace CMakeProjectManager
+
+#endif

src/plugins/cmakeprojectmanager/servermodereader.h

@@ -67,6 +67,10 @@ private:
     void handleProgress(int min, int cur, int max, const QString &inReplyTo);
     void handleSignal(const QString &signal, const QVariantMap &data);
 
+    int calculateProgress(const int minRange, const int min,
+                          const int cur,
+                          const int max, const int maxRange);
+
     struct Target;
     struct Project;
 
@@ -151,6 +155,10 @@ private:
     QList<FileGroup *> m_fileGroups;
 
     CMakeParser m_parser;
+
+#if defined(WITH_TESTS)
+    friend class CMakeProjectPlugin;
+#endif
 };
 
 } // namespace Internal