Change qt.conf key Qml2Imports to QmlImports

[ChangeLog][qt.conf] The key Paths/Qml2Imports has been renamed to
Paths/QmlImports. For backwards-compatibility, Paths/Qml2Imports is
still accepted and acts as default value for when Paths/QmlImports is
not present.

Fixes: QTBUG-98335
Change-Id: If7ffedd281eb8a87e8ab1a2b69a823e615c33541
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>
Reviewed-by: Alexey Edelev <alexey.edelev@qt.io>
Reviewed-by: Kai Koehne <kai.koehne@qt.io>

3 files changed, 46 insertions, 32 deletions

diff --git a/qmake/qmakelibraryinfo.cpp b/qmake/qmakelibraryinfo.cpp
index b501cfc5f6..59a4e6eb59 100644
--- a/qmake/qmakelibraryinfo.cpp
+++ b/qmake/qmakelibraryinfo.cpp
@@ -148,21 +148,14 @@ static QLibraryInfo::LibraryPath hostToTargetPathEnum(int loc)
     Q_UNREACHABLE();
 }
 
-struct LocationInfo
+static QLibraryInfoPrivate::LocationInfo defaultLocationInfo(int loc)
 {
-    QString key;
-    QString defaultValue;
-};
-
-static LocationInfo defaultLocationInfo(int loc)
-{
-    LocationInfo result;
+    QLibraryInfoPrivate::LocationInfo result;
 
     if (loc < QMakeLibraryInfo::FirstHostPath) {
-        QLibraryInfoPrivate::keyAndDefault(static_cast<QLibraryInfo::LibraryPath>(loc),
-                                   &result.key, &result.defaultValue);
+        result = QLibraryInfoPrivate::locationInfo(static_cast<QLibraryInfo::LibraryPath>(loc));
     } else if (loc <= QMakeLibraryInfo::LastHostPath) {
-        QLibraryInfoPrivate::keyAndDefault(hostToTargetPathEnum(loc), &result.key, &result.defaultValue);
+        result = QLibraryInfoPrivate::locationInfo(hostToTargetPathEnum(loc));
         result.key.prepend(QStringLiteral("Host"));
     } else if (loc == QMakeLibraryInfo::SysrootPath) {
         result.key = QStringLiteral("Sysroot");
@@ -219,7 +212,7 @@ QString QMakeLibraryInfo::rawLocation(int loc, QMakeLibraryInfo::PathGroup group
         || (group = orig_group, false)) {
         fromConf = true;
 
-        LocationInfo locinfo = defaultLocationInfo(loc);
+        QLibraryInfoPrivate::LocationInfo locinfo = defaultLocationInfo(loc);
         if (!locinfo.key.isNull()) {
             QSettings *config = QLibraryInfoPrivate::configuration();
             Q_ASSERT(config != nullptr);
@@ -229,7 +222,15 @@ QString QMakeLibraryInfo::rawLocation(int loc, QMakeLibraryInfo::PathGroup group
                                                      : group == EffectivePaths ? "EffectivePaths"
                                                                                : "Paths"));
 
-            ret = config->value(locinfo.key).toString();
+            if (locinfo.fallbackKey.isNull()) {
+                ret = config->value(locinfo.key, locinfo.defaultValue).toString();
+            } else {
+                QVariant v = config->value(locinfo.key);
+                if (!v.isValid())
+                    v = config->value(locinfo.fallbackKey, locinfo.defaultValue);
+                ret = v.toString();
+            }
+
             if (ret.isEmpty()) {
                 if (loc == HostPrefixPath || loc == TargetSpecPath || loc == HostSpecPath
                            || loc == SysrootifyPrefixPath || loc == QLibraryInfo::PrefixPath) {
diff --git a/src/corelib/global/qlibraryinfo.cpp b/src/corelib/global/qlibraryinfo.cpp
index 97232d8120..c31e1fdecf 100644
--- a/src/corelib/global/qlibraryinfo.cpp
+++ b/src/corelib/global/qlibraryinfo.cpp
@@ -490,8 +490,7 @@ static QString getPrefix()
 #endif
 }
 
-void QLibraryInfoPrivate::keyAndDefault(QLibraryInfo::LibraryPath loc, QString *key,
-                                              QString *value)
+QLibraryInfoPrivate::LocationInfo QLibraryInfoPrivate::locationInfo(QLibraryInfo::LibraryPath loc)
 {
     /*
      * To add a new entry in QLibraryInfo::LibraryPath, add it to the enum
@@ -512,9 +511,7 @@ void QLibraryInfoPrivate::keyAndDefault(QLibraryInfo::LibraryPath loc, QString *
         "Binaries", "bin",
         "Plugins", "plugins", // should be ${ArchData}/plugins
 
-        // TODO: Find a way to rename this to QmlImports
-        //       without breaking compatibility with old qt.conf files.
-        "Qml2Imports", "qml", // should be ${ArchData}/qml
+        "QmlImports", "qml", // should be ${ArchData}/qml
 
         "ArchData", ".",
         "Data", ".",
@@ -526,18 +523,21 @@ void QLibraryInfoPrivate::keyAndDefault(QLibraryInfo::LibraryPath loc, QString *
     static_assert(dot.size() == 1);
     static_assert(dot[0] == '.');
 
+    LocationInfo result;
+
     if (int(loc) < qtConfEntries.count()) {
-        *key = QLatin1String(qtConfEntries.viewAt(loc * 2));
-        *value = QLatin1String(qtConfEntries.viewAt(loc * 2 + 1));
+        result.key = QLatin1String(qtConfEntries.viewAt(loc * 2));
+        result.defaultValue = QLatin1String(qtConfEntries.viewAt(loc * 2 + 1));
+        if (result.key == u"QmlImports")
+            result.fallbackKey = u"Qml2Imports"_qs;
 #ifndef Q_OS_WIN // On Windows we use the registry
     } else if (loc == QLibraryInfo::SettingsPath) {
-        *key = QLatin1String("Settings");
-        *value = QLatin1String(dot);
+        result.key = QLatin1String("Settings");
+        result.defaultValue = QLatin1String(dot);
 #endif
-    } else {
-        key->clear();
-        value->clear();
     }
+
+    return result;
 }
 
 /*! \fn QString QLibraryInfo::location(LibraryLocation loc)
@@ -559,15 +559,21 @@ QString QLibraryInfo::path(LibraryPath p)
     if (havePaths()) {
         fromConf = true;
 
-        QString key;
-        QString defaultValue;
-        QLibraryInfoPrivate::keyAndDefault(loc, &key, &defaultValue);
-        if (!key.isNull()) {
+        auto li = QLibraryInfoPrivate::locationInfo(loc);
+        if (!li.key.isNull()) {
             QSettings *config = QLibraryInfoPrivate::configuration();
             Q_ASSERT(config != nullptr);
             config->beginGroup(QLatin1String("Paths"));
 
-            ret = config->value(key, defaultValue).toString();
+            if (li.fallbackKey.isNull()) {
+                ret = config->value(li.key, li.defaultValue).toString();
+            } else {
+                QVariant v = config->value(li.key);
+                if (!v.isValid())
+                    v = config->value(li.fallbackKey, li.defaultValue);
+                ret = v.toString();
+            }
+
             int startIndex = 0;
             forever {
                 startIndex = ret.indexOf(QLatin1Char('$'), startIndex);
diff --git a/src/corelib/global/qlibraryinfo_p.h b/src/corelib/global/qlibraryinfo_p.h
index a0900f010b..caed0feb84 100644
--- a/src/corelib/global/qlibraryinfo_p.h
+++ b/src/corelib/global/qlibraryinfo_p.h
@@ -69,8 +69,15 @@ public:
     static void reload();
     static QString qtconfManualPath;
 #endif
-    static void keyAndDefault(QLibraryInfo::LibraryPath loc, QString *key,
-                                                  QString *value);
+
+    struct LocationInfo
+    {
+        QString key;
+        QString defaultValue;
+        QString fallbackKey;
+    };
+
+    static LocationInfo locationInfo(QLibraryInfo::LibraryPath loc);
 };
 
 QT_END_NAMESPACE