2 files changed, 165 insertions, 0 deletions
diff --git a/src/tests/common/game_presets.cpp b/src/tests/common/game_presets.cpp
new file mode 100644
index 0000000000..481f5c5e1d
--- /dev/null
+++ b/src/tests/common/game_presets.cpp
@@ -0,0 +1,111 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include <memory>
+#include <catch2/catch_test_macros.hpp>
+#include "common/game_presets.h"
+
+namespace {
+void SetConflictingPreferences(Settings::Values& settings, bool per_game) {
+    const auto set = [per_game](auto& setting, auto value) {
+        setting.SetGlobal(!per_game);
+        setting.SetValue(value);
+    };
+    set(settings.renderer_backend, Settings::RendererBackend::Null);
+    set(settings.resolution_setup, Settings::ResolutionSetup::Res2X);
+    set(settings.gpu_accuracy, Settings::GpuAccuracy::High);
+    set(settings.use_asynchronous_shaders, false);
+    set(settings.astc_recompression, Settings::AstcRecompression::Uncompressed);
+    set(settings.vram_usage_mode, Settings::VramUsageMode::Aggressive);
+    set(settings.use_reactive_flushing, true);
+    set(settings.vsync_mode, Settings::VSyncMode::Immediate);
+    set(settings.scaling_filter, Settings::ScalingFilter::NearestNeighbor);
+    set(settings.anti_aliasing, Settings::AntiAliasing::Smaa);
+}
+
+void CheckPreset(const Settings::Values& settings) {
+    CHECK(settings.renderer_backend.GetValue() == Settings::RendererBackend::Vulkan);
+    CHECK(settings.resolution_setup.GetValue() == Settings::ResolutionSetup::Res1X);
+    CHECK(settings.gpu_accuracy.GetValue() == Settings::GpuAccuracy::Low);
+    CHECK(settings.use_asynchronous_shaders.GetValue());
+    CHECK(settings.astc_recompression.GetValue() == Settings::AstcRecompression::Bc3);
+    CHECK(settings.vram_usage_mode.GetValue() == Settings::VramUsageMode::Conservative);
+    CHECK_FALSE(settings.use_reactive_flushing.GetValue());
+    CHECK(settings.vsync_mode.GetValue() == Settings::VSyncMode::FifoRelaxed);
+    CHECK(settings.use_docked_mode.GetValue() == Settings::ConsoleMode::Handheld);
+    CHECK(settings.scaling_filter.GetValue() == Settings::ScalingFilter::ScaleForce);
+    CHECK(settings.anti_aliasing.GetValue() == Settings::AntiAliasing::Fxaa);
+}
+
+void CheckPreferences(const Settings::Values& settings, bool global = false) {
+    CHECK(settings.renderer_backend.GetValue(global) == Settings::RendererBackend::Null);
+    CHECK(settings.resolution_setup.GetValue(global) == Settings::ResolutionSetup::Res2X);
+    CHECK(settings.gpu_accuracy.GetValue(global) == Settings::GpuAccuracy::High);
+    CHECK_FALSE(settings.use_asynchronous_shaders.GetValue(global));
+    CHECK(settings.astc_recompression.GetValue(global) ==
+          Settings::AstcRecompression::Uncompressed);
+    CHECK(settings.vram_usage_mode.GetValue(global) == Settings::VramUsageMode::Aggressive);
+    CHECK(settings.use_reactive_flushing.GetValue(global));
+    CHECK(settings.vsync_mode.GetValue(global) == Settings::VSyncMode::Immediate);
+    CHECK(settings.scaling_filter.GetValue(global) == Settings::ScalingFilter::NearestNeighbor);
+    CHECK(settings.anti_aliasing.GetValue(global) == Settings::AntiAliasing::Smaa);
+}
+} // namespace
+
+TEST_CASE("Display filter defaults use ScaleForce and FXAA", "[game_presets]") {
+    auto settings = std::make_unique<Settings::Values>();
+    CHECK(settings->scaling_filter.GetDefault() == Settings::ScalingFilter::ScaleForce);
+    CHECK(settings->anti_aliasing.GetDefault() == Settings::AntiAliasing::Fxaa);
+}
+
+TEST_CASE("Accepted MKW settings replace visible global preferences", "[game_presets]") {
+    auto settings = std::make_unique<Settings::Values>();
+    SetConflictingPreferences(*settings, false);
+    Settings::SetMarioKartWorldRecommendedSettings(*settings, true);
+    CheckPreset(*settings);
+    CHECK(settings->renderer_backend.UsingGlobal());
+    CHECK(settings->gpu_accuracy.UsingGlobal());
+    CHECK(settings->renderer_backend.GetValue(true) == Settings::RendererBackend::Vulkan);
+    CHECK(settings->gpu_accuracy.GetValue(true) == Settings::GpuAccuracy::Low);
+}
+
+TEST_CASE("MKW preset overrides saved settings for the session", "[game_presets]") {
+    auto settings = std::make_unique<Settings::Values>();
+    SetConflictingPreferences(*settings, false);
+    SetConflictingPreferences(*settings, true);
+    REQUIRE(
+        Settings::ApplyMarioKartWorldPreset(*settings, Settings::MarioKartWorldProgramId, true));
+    CheckPreset(*settings);
+    CheckPreferences(*settings, true);
+    for (const auto& restore : settings->linkage.restore_functions) {
+        restore();
+    }
+    CheckPreferences(*settings);
+    CHECK(settings->renderer_backend.UsingGlobal());
+    CHECK(settings->resolution_setup.UsingGlobal());
+    REQUIRE(
+        Settings::ApplyMarioKartWorldPreset(*settings, Settings::MarioKartWorldProgramId, true));
+    CheckPreset(*settings);
+}
+
+TEST_CASE("MKW preset does not change unrelated games", "[game_presets]") {
+    auto settings = std::make_unique<Settings::Values>();
+    SetConflictingPreferences(*settings, false);
+    CHECK_FALSE(Settings::ApplyMarioKartWorldPreset(*settings, 0, true));
+    CHECK_FALSE(Settings::ApplyMarioKartWorldPreset(*settings,
+                                                    Settings::MarioKartWorldProgramId + 1, true));
+    CheckPreferences(*settings);
+    CHECK(settings->renderer_backend.UsingGlobal());
+    CHECK(settings->resolution_setup.UsingGlobal());
+}
+
+TEST_CASE("Declining the MKW preset preserves global and per-game preferences", "[game_presets]") {
+    auto settings = std::make_unique<Settings::Values>();
+    for (bool per_game : {false, true}) {
+        SetConflictingPreferences(*settings, per_game);
+        CHECK_FALSE(Settings::ApplyMarioKartWorldPreset(*settings,
+                                                        Settings::MarioKartWorldProgramId, false));
+        CheckPreferences(*settings);
+        CHECK(settings->renderer_backend.UsingGlobal() == !per_game);
+        CHECK(settings->resolution_setup.UsingGlobal() == !per_game);
+    }
+}
diff --git a/src/tests/common/slot_vector.cpp b/src/tests/common/slot_vector.cpp
new file mode 100644
index 0000000000..d8f242085c
--- /dev/null
+++ b/src/tests/common/slot_vector.cpp
@@ -0,0 +1,54 @@
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include <map>
+#include <random>
+#include <vector>
+#include <catch2/catch_test_macros.hpp>
+#include "common/slot_vector.h"
+
+TEST_CASE("SlotVector visits live entries across empty bitmap words", "[common]") {
+    Common::SlotVector<u32> slots;
+    std::vector<Common::SlotId> ids;
+    for (u32 i = 0; i < 513; ++i) {
+        ids.push_back(slots.insert(i));
+    }
+    for (u32 i = 0; i < 512; ++i) {
+        slots.erase(ids[i]);
+    }
+    auto it = slots.begin();
+    REQUIRE(it != slots.end());
+    REQUIRE((*it).first == ids[512]);
+    REQUIRE(*(*it).second == 512);
+    REQUIRE(++it == slots.end());
+    slots.erase(ids[512]);
+    REQUIRE(slots.begin() == slots.end());
+}
+
+TEST_CASE("SlotVector sparse iteration matches a live-entry model", "[common]") {
+    Common::SlotVector<u32> slots;
+    std::map<u32, u32> live;
+    std::mt19937 random{9813};
+    for (u32 batch = 0; batch < 200; ++batch) {
+        for (u32 i = 0; i < 100; ++i) {
+            if (!live.empty() && (random() % 3) == 0) {
+                auto selected = live.begin();
+                std::advance(selected, random() % live.size());
+                slots.erase(Common::SlotId{selected->first});
+                live.erase(selected);
+            } else {
+                const u32 value = random();
+                const auto id = slots.insert(value);
+                live.emplace(id.Value(), value);
+            }
+        }
+        auto expected = live.begin();
+        for (const auto [id, value] : slots) {
+            REQUIRE(expected != live.end());
+            REQUIRE(id.Value() == expected->first);
+            REQUIRE(*value == expected->second);
+            ++expected;
+        }
+        REQUIRE(expected == live.end());
+    }
+}