Debugger: Fix automatic source mapping for Qt

- The QtVersion::sourcePath() was wrong because QT_INSTALL_PREFIX/src
  doesn't return the right path. Work around by checking if sources are
  found, and otherwise trying the location that we know the installers
  to put them.
- Pass the sourcePath along to the debugger run control, and use that
  instead of looking for qmake in the PATH (which fails because it is
  not in PATH).

Fixes: QTCREATORBUG-28950
Change-Id: Iffa262d6c87dbc979c449d43cd4a85e1320bcd37
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/debugger/debuggerengine.h

@@ -157,6 +157,7 @@ public:
     Utils::FilePath debugInfoLocation; // Gdb "set-debug-file-directory".
     QStringList debugSourceLocation; // Gdb "directory"
     QString qtPackageSourceLocation;
+    Utils::FilePath qtSourceLocation;
     bool isSnapshot = false; // Set if created internally.
     ProjectExplorer::Abi toolChainAbi;
 

src/plugins/debugger/debuggerruncontrol.cpp

@@ -863,8 +863,10 @@ DebuggerRunTool::DebuggerRunTool(RunControl *runControl, AllowTerminal allowTerm
     m_runParameters.debugger = DebuggerKitAspect::runnable(kit);
     m_runParameters.cppEngineType = DebuggerKitAspect::engineType(kit);
 
-    if (QtSupport::QtVersion *qtVersion = QtSupport::QtKitAspect::qtVersion(kit))
+    if (QtSupport::QtVersion *qtVersion = QtSupport::QtKitAspect::qtVersion(kit)) {
         m_runParameters.qtPackageSourceLocation = qtVersion->qtPackageSourcePath().toString();
+        m_runParameters.qtSourceLocation = qtVersion->sourcePath();
+    }
 
     if (auto aspect = runControl->aspect<DebuggerRunConfigurationAspect>()) {
         if (!aspect->useCppDebugger)

src/plugins/debugger/debuggersourcepathmappingwidget.cpp

@@ -415,47 +415,18 @@ void DebuggerSourcePathMappingWidget::slotEditTargetFieldChanged()
     }
 }
 
-// Find Qt installation by running qmake
-static QString findQtInstallPath(const FilePath &qmakePath)
-{
-    if (qmakePath.isEmpty())
-        return QString();
-    Process proc;
-    proc.setCommand({qmakePath, {"-query", "QT_INSTALL_HEADERS"}});
-    proc.start();
-    if (!proc.waitForFinished()) {
-        qWarning("%s: Timeout running '%s'.", Q_FUNC_INFO, qPrintable(qmakePath.toString()));
-        return QString();
-    }
-    if (proc.exitStatus() != QProcess::NormalExit) {
-        qWarning("%s: '%s' crashed.", Q_FUNC_INFO, qPrintable(qmakePath.toString()));
-        return QString();
-    }
-    const QByteArray ba = proc.readAllRawStandardOutput().trimmed();
-    QDir dir(QString::fromLocal8Bit(ba));
-    if (dir.exists() && dir.cdUp())
-        return dir.absolutePath();
-    return QString();
-}
-
 /* Merge settings for an installed Qt (unless another setting is already in the map. */
 SourcePathMap mergePlatformQtPath(const DebuggerRunParameters &sp, const SourcePathMap &in)
 {
-    const FilePath qmake = BuildableHelperLibrary::findSystemQt(sp.inferior.environment);
-    // FIXME: Get this from the profile?
-    //        We could query the QtVersion for this information directly, but then we
-    //        will need to add a dependency on QtSupport to the debugger.
-    //
-    //        The profile could also get a function to extract the required information from
-    //        its information to avoid this dependency (as we do for the environment).
-    const QString qtInstallPath = findQtInstallPath(qmake);
-    if (qtInstallPath.isEmpty())
+    static const QString qglobal = "qtbase/src/corelib/global/qglobal.h";
+    const FilePath sourceLocation = sp.qtSourceLocation;
+    if (!(sourceLocation / qglobal).exists())
         return in;
 
     SourcePathMap rc = in;
     for (const QString &buildPath : qtBuildPaths()) {
         if (!rc.contains(buildPath)) // Do not overwrite user settings.
-            rc.insert(buildPath, qtInstallPath + "/../Src");
+            rc.insert(buildPath, sourceLocation.path());
     }
     return rc;
 }

src/plugins/qtsupport/baseqtversion.cpp

@@ -1861,9 +1861,23 @@ FilePath QtVersionPrivate::mkspecFromVersionInfo(const QHash<ProKey, ProString>
 FilePath QtVersionPrivate::sourcePath(const QHash<ProKey, ProString> &versionInfo)
 {
     const QString qt5Source = qmakeProperty(versionInfo, "QT_INSTALL_PREFIX/src");
-    if (!qt5Source.isEmpty())
-        return FilePath::fromString(QFileInfo(qt5Source).canonicalFilePath());
+    if (!qt5Source.isEmpty()) {
+        // Can be wrong for the Qt installers :/
+        // Check if we actually find sources, otherwise try what the online installer does.
+        const auto source = FilePath::fromString(QFileInfo(qt5Source).canonicalFilePath());
+        static const QString qglobal = "qtbase/src/corelib/global/qglobal.h";
+        if (!(source / qglobal).exists()) {
+            const auto install = FilePath::fromString(
+                                     qmakeProperty(versionInfo, "QT_INSTALL_PREFIX"))
+                                     .canonicalPath();
+            const FilePath otherSource = install / ".." / "Src";
+            if ((otherSource / qglobal).exists())
+                return otherSource.cleanPath();
+        }
+        return source;
+    }
 
+    // TODO The .qmake.cache workaround doesn't work anymore since Qt is built with CMake
     const QString installData = qmakeProperty(versionInfo, "QT_INSTALL_PREFIX");
     QString sourcePath = installData;
     QFile qmakeCache(installData + "/.qmake.cache");