Migrate -dbcache setting from QSettings to settings.json

This is just the first of multiple settings that will be stored in the bitcoin
persistent setting file and shared with bitcoind, instead of being stored as Qt
settings backed by the windows registry or platform specific config files which
are ignored by bitcoind.

Co-Authored-By: furszy <matiasfurszyfer@protonmail.com>

6 files changed, 52 insertions, 13 deletions

diff --git a/src/qt/test/addressbooktests.cpp b/src/qt/test/addressbooktests.cpp
index ededde4da9..bc9dbae44a 100644
--- a/src/qt/test/addressbooktests.cpp
+++ b/src/qt/test/addressbooktests.cpp
@@ -128,6 +128,8 @@ void TestAddAddressesToSendBook(interfaces::Node& node)
     // Initialize relevant QT models.
     std::unique_ptr<const PlatformStyle> platformStyle(PlatformStyle::instantiate("other"));
     OptionsModel optionsModel(node);
+    bilingual_str error;
+    QVERIFY(optionsModel.Init(error));
     ClientModel clientModel(node, &optionsModel);
     WalletContext& context = *node.walletLoader().context();
     AddWallet(context, wallet);
diff --git a/src/qt/test/apptests.cpp b/src/qt/test/apptests.cpp
index 9648ef6188..6fc7a52435 100644
--- a/src/qt/test/apptests.cpp
+++ b/src/qt/test/apptests.cpp
@@ -70,14 +70,9 @@ void AppTests::appTests()
     }
 #endif
 
-    fs::create_directories([] {
-        BasicTestingSetup test{CBaseChainParams::REGTEST}; // Create a temp data directory to backup the gui settings to
-        return gArgs.GetDataDirNet() / "blocks";
-    }());
-
     qRegisterMetaType<interfaces::BlockAndHeaderTipInfo>("interfaces::BlockAndHeaderTipInfo");
     m_app.parameterSetup();
-    m_app.createOptionsModel(true /* reset settings */);
+    QVERIFY(m_app.createOptionsModel(true /* reset settings */));
     QScopedPointer<const NetworkStyle> style(NetworkStyle::instantiate(Params().NetworkIDString()));
     m_app.setupPlatformStyle();
     m_app.createWindow(style.data());
diff --git a/src/qt/test/optiontests.cpp b/src/qt/test/optiontests.cpp
index 2ef9230c59..fb8b78f66e 100644
--- a/src/qt/test/optiontests.cpp
+++ b/src/qt/test/optiontests.cpp
@@ -13,6 +13,40 @@
 
 #include <univalue.h>
 
+#include <fstream>
+
+OptionTests::OptionTests(interfaces::Node& node) : m_node(node)
+{
+    gArgs.LockSettings([&](util::Settings& s) { m_previous_settings = s; });
+}
+
+void OptionTests::init()
+{
+    // reset args
+    gArgs.LockSettings([&](util::Settings& s) { s = m_previous_settings; });
+    gArgs.ClearPathCache();
+}
+
+void OptionTests::migrateSettings()
+{
+    // Set legacy QSettings and verify that they get cleared and migrated to
+    // settings.json
+    QSettings settings;
+    settings.setValue("nDatabaseCache", 600);
+
+    settings.sync();
+
+    OptionsModel options{m_node};
+    bilingual_str error;
+    QVERIFY(options.Init(error));
+    QVERIFY(!settings.contains("nDatabaseCache"));
+
+    std::ifstream file(gArgs.GetDataDirNet() / "settings.json");
+    QCOMPARE(std::string(std::istreambuf_iterator<char>(file), std::istreambuf_iterator<char>()).c_str(), "{\n"
+        "    \"dbcache\": \"600\"\n"
+        "}\n");
+}
+
 void OptionTests::integerGetArgBug()
 {
     // Test regression https://github.com/bitcoin/bitcoin/issues/24457. Ensure
@@ -23,7 +57,8 @@ void OptionTests::integerGetArgBug()
         settings.rw_settings["prune"] = 3814;
     });
     gArgs.WriteSettingsFile();
-    OptionsModel{m_node};
+    bilingual_str error;
+    QVERIFY(OptionsModel{m_node}.Init(error));
     gArgs.LockSettings([&](util::Settings& settings) {
         settings.rw_settings.erase("prune");
     });
@@ -36,8 +71,6 @@ void OptionTests::parametersInteraction()
     // It was fixed via https://github.com/bitcoin-core/gui/pull/568.
     // With fListen=false in ~/.config/Bitcoin/Bitcoin-Qt.conf and all else left as default,
     // bitcoin-qt should set both -listen and -listenonion to false and start successfully.
-    gArgs.ClearPathCache();
-
     gArgs.LockSettings([&](util::Settings& s) {
         s.forced_settings.erase("listen");
         s.forced_settings.erase("listenonion");
@@ -48,7 +81,8 @@ void OptionTests::parametersInteraction()
     QSettings settings;
     settings.setValue("fListen", false);
 
-    OptionsModel{m_node};
+    bilingual_str error;
+    QVERIFY(OptionsModel{m_node}.Init(error));
 
     const bool expected{false};
 
diff --git a/src/qt/test/optiontests.h b/src/qt/test/optiontests.h
index 257a0b65be..286d785572 100644
--- a/src/qt/test/optiontests.h
+++ b/src/qt/test/optiontests.h
@@ -6,6 +6,8 @@
 #define BITCOIN_QT_TEST_OPTIONTESTS_H
 
 #include <qt/optionsmodel.h>
+#include <univalue.h>
+#include <util/settings.h>
 
 #include <QObject>
 
@@ -13,14 +15,17 @@ class OptionTests : public QObject
 {
     Q_OBJECT
 public:
-    explicit OptionTests(interfaces::Node& node) : m_node(node) {}
+    explicit OptionTests(interfaces::Node& node);
 
 private Q_SLOTS:
+    void init(); // called before each test function execution.
+    void migrateSettings();
     void integerGetArgBug();
     void parametersInteraction();
 
 private:
     interfaces::Node& m_node;
+    util::Settings m_previous_settings;
 };
 
 #endif // BITCOIN_QT_TEST_OPTIONTESTS_H
diff --git a/src/qt/test/test_main.cpp b/src/qt/test/test_main.cpp
index aeedd92834..de23f51c92 100644
--- a/src/qt/test/test_main.cpp
+++ b/src/qt/test/test_main.cpp
@@ -58,9 +58,10 @@ int main(int argc, char* argv[])
     // regtest params.
     //
     // All tests must use their own testing setup (if needed).
-    {
+    fs::create_directories([] {
         BasicTestingSetup dummy{CBaseChainParams::REGTEST};
-    }
+        return gArgs.GetDataDirNet() / "blocks";
+    }());
 
     std::unique_ptr<interfaces::Init> init = interfaces::MakeGuiInit(argc, argv);
     gArgs.ForceSetArg("-listen", "0");
diff --git a/src/qt/test/wallettests.cpp b/src/qt/test/wallettests.cpp
index bc06f0f23b..7671bfc739 100644
--- a/src/qt/test/wallettests.cpp
+++ b/src/qt/test/wallettests.cpp
@@ -185,6 +185,8 @@ void TestGUI(interfaces::Node& node)
     SendCoinsDialog sendCoinsDialog(platformStyle.get());
     TransactionView transactionView(platformStyle.get());
     OptionsModel optionsModel(node);
+    bilingual_str error;
+    QVERIFY(optionsModel.Init(error));
     ClientModel clientModel(node, &optionsModel);
     WalletContext& context = *node.walletLoader().context();
     AddWallet(context, wallet);