Middle-button pan, persistent tool settings, Auto Select's foreground rule, the new icon (12.6b)

src/Document/ToolDefaults.cpp

@@ -0,0 +1,33 @@
+#include "Document/ToolDefaults.h"
+#include "Logging.h"
+#include <QSettings>
+
+namespace {
+const QString prefix = QStringLiteral("tool.");
+// Swift's XCTest check: only the app keeps the toggles.
+bool enabled = false;
+}
+
+void ToolDefaults::enable()
+{
+    enabled = true;
+}
+
+bool ToolDefaults::boolean(const QString &key, bool fallback)
+{
+    if (!enabled)
+        return fallback;
+    // The settings file keeps text; this run's writes are booleans.
+    const QString stored = QSettings().value(prefix + key).toString();
+    if (stored == QLatin1String("true") || stored == QLatin1String("false"))
+        return stored == QLatin1String("true");
+    if (!stored.isEmpty())
+        qCWarning(lcApp).noquote() << "ignoring the tool setting" << key << "of" << stored;
+    return fallback;
+}
+
+void ToolDefaults::set(bool value, const QString &key)
+{
+    if (enabled)
+        QSettings().setValue(prefix + key, value);
+}